Tallgrass Savanna - IA

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1. Little bluestem-live oak savanna- This is the Texas live oak-tallgrass savanna at climax stage. As a single-species understory to old-growth live oaks, little bluestem forms a consociation almost to complete exclusion of any other herbaceous species. The only contender (and it is barely that) for an associate species is, interestingly, the annual colonizer of old-fields known variously as marestail, horse-weed, or old-field fleabane (Conyza canadensis= Erigerion canadensis). There is good regeneration of the live oak. (Note young trees at far left margin of slide and the clump of young trees with gray trunks immediately behind and to the right of the the right front mature live oak.) A bromeliad known as ball moss (Tillandsia recurvata) is growing on branches of the live oaks. This is as beautiful and pristine a savanna as the author ever encountered.

Atascosa County, Texas. Autumnal aspect, October. As was the case of the live oak-mixed prairie savannah this vegetation defies precise FRES and Kuchler designations, primarily perhaps because these classifications did not involve mapping at this fine a scale. This community could be interpreted as a cover type variant or form of K-72 (Oak Savanna) though in physiogonomy it clearly resenmbles the Florida live oak hammock which seemed to be most closely K-81 (Live Oak-Sea Oats). Yet, it is not the coastal live oak- sea oats understory. Neither is there an SRM designation. East Central Texas Plains- Southern Post Oak Savanna Ecoregion, 33b (Griffith et al., 2004).

2. Live oak-mixed prairie savanna- A savannah of old-growth live oak (with a disturbingly limited regeneration) and a grass understory dominated by sideoats grama followed closely by four-flower trichloris, silver bluestem, little bluestem, and panicgrasses (including some upland switchgrass) but with very limited shortgrass component of buffalograss, hairy grama, and Texas grama. The dominant (and conspicuous) forb which is growing adjacent to oak trunks is Turk's cap (Malvaviscus drummomdii). A sandy loam range site in Good range condition class due to the limited cover of little bluestem, the dominant decreaser. Live Oak County, Texas. October. Defies precise FRES and Kuchler classification. Most closely resembles Florida live oak hammock in physiogonomy and dominant tree species: FRES No. 16, (Live Oak-Gum-Cypress Forest Ecosystem) or No. 15 (Oak-Hickory Forest Ecosystem), specifically K-72 (Oak Savanna) thereof. On basis of understory grass community it is a deteriorated form of bluestem prairie (K-66) or a bluestem-grama prairie (K-62). Yet neither is correct because this is clearly part of FRES 32 (Texas Savanna Ecosystem) either K-55 (Mesquite-Live Oak Savanna) or K-78 (Mesquite-Oak savanna). East Central Texas Plains- Southern Post Oak Savanna Ecoregion, 33b (Griffith et al., 2004).

Location Note: Live oak mottes on (within) western Gulf Coast sand tallgrass prairie could be interpreted as a savanna or savanna-like range type. This range vegetation was prinicpally treated under Woodlands and Forests in the Miscellaneous chapter with some coverage under Grasslands, the Tallgrass Prairie (Coastal) chapter. If live oak mottes are composed mostly of one or just a few individual trees (= numerous trunks from creeping rootstocks of the same, tree; "trees" all of the same genotype so as to be clones) these groves widely scattered across sacahuista or seacoast bluestem prairie form climax range vegetation that is correctly interpreted as savanna in both genetic and structural senses. When previously scattered live oak-dominated mottes have converged or coalesced to form range vegetation that is more-or-less completely dominated by trees, like live oak, with closed (or nearly so) canopies and with or without an herbaceous storey an extensive woodland (or even forest) has developed. Successional status of such tree-dominated range vegetation remains open to interpretation (it is probably most precisely seen as disturbance climax or brush invasion), but it is by definition NOT savanna and as such was not included with similar woody-herbaceous ecotones like those in this chapter (nor in others dealing with natural savannahs)..

3. Texas post oak savanna- A consociation of little bluestem (with some Indiangrass as associate) as an understory to post oak (Quercus stellata).Actually two prominent herbaceous layers: various rosette Panicum species beneath the tallgrass bluestem layer. Bexar County, Texas.Hiemal aspect, February. No specific FRES designation, but an ecotone between FRES No. 15 (Oak-Hickory Forest Ecosystem) and FRES No. 39 (Prairie Ecosystem). K-73 (Mosaic of Bluestem Prairie [K-66] and Oak-Hickory Forest [K-91]) but also features of K-75 (Cross Timbers). SRM 732 (Cross Timbers, Texas; Little Bluestem-Post Oak). East Central Texas Plains- Southern Post Oak Savanna Ecoregion, 33b (Griffith et al., 2004).

4. Another view of post oak savanna (also of little bluestem and Indiangrass)- Open understory maintained by prescribed burning.Some patches of western ragweed (Ambrosia psilostachya).

Wichita Mountains National Wildlife Refuge. Commanche County, Oklahoma. October. Ecotone between FRES No. 15 (Oak-Hickory Forest Ecosystem) and FRESNo. 39 (Prairie Ecosystem), but more like K-75 (Cross Timbers) than K-73 (Oak-Hickory Forest and Bluestem Prairie Mosaic). SRM 732 (Cross Timbers, Texas; Little Bluestem-Post Oak). Central Great Plains- Wichita Mountains Ecoregion, 27k (Woods et al., 2005).

Location note: another example of post oak savanna on the Wichita Mountains National Wildlife Refuge that was of larger trees (with lower density) and with an herbaceous understorey of mixed prairie was presented later (below) in this chapter where it seemed more appropriate and consistent with this professor's "lesson plan". This example of post oak and tallgrass species was included here to introduce the subject of savannahs.

Cross Timbers

The Cross Timbers is, or are (as the grammatical case may be), some of the more unique and enigmatic kinds (or forms, expressions, etc.) of vegetation in North America. Besides being used as a term for a "vegetation type" and an ecosystem or landscape of a geographic region-scale, Cross Timbers also entered into regional history, literature, and cultural-social character features. Washington Irving probably did the most to essentially enshrine Cross Timber[s] in his famous A Tour on the Prairies (1835). Later, Cross Timbers became a long-established trademark-like catch word for commercial use in regional promotion of real estate, tourism, and so on. Cross Timbers took on poetic and historic connotations as well as general biological and specific ecological meanings and descriptions. By and large these different usages, views, or ways of seeing the Cross Timbers complemented each other and made for a term or term-like phrase equal in its own way with the likes of Great Plains, Piedmont, Edwards Plateau, pine barrens, Great Lakes forests, Flint Hills, Ozarks, Great Basin, Palouse Prairie, or Pacific Northwest. In these instances of common common "every day" usage, at least with some groups of people, Cross Timbers as the specific name of a physiographic province or plant formation became merged in common parlance with the general name for a region which in turn might be a combination of strict geologic or cartographic interpretation with basic biological features and historic-economic-cultural characteristics. Such is the very definition of Geography, and Cross Timbers is a geographical as well as an ecological designation.

In this context, readers have been blessed with an outstanding treatise of the Cross Timbers in The Cast Iron Forest (Francaviglia, 2000). This comprehensive account along with Dyksterhuis (1948) and Bruner (1931), both of which were referred to below, will provide beginning students with all they need to know to understand the regional range community and the range cover type long recognized and designated the Cross Timbers. Another recent, and also outstanding, treatment of the Cross Timbers is that of Hoagland et al. in Anderson et al. (1999, ps. 231-245).

A thumbnail sketch of a few basic features of this range vegetation seemed in order. The Cross Timbers is generally a savanna as a transition zone between the westernmost outpost of the oak-hickory forest and the eastern edge of the great interior grasslands known as tallgrass prairie. The Cross Timbers is climax vegetation. This vegetation extends from Texas northward and slightly eastward to southern Kansas. Cross Timbers generally occurs on soils for which the parent material is sandstone of various geologic ages (Francaviglia, 2000, Fig. 1-8, p. 24). As tree-dominated or, at least, tree-containing communities in North America go, the Cross Timbers have probably been less altered by white man than most native vegetation of which trees are or were a major component. Lastly, but by no means completely, Cross Timbers remains a major range type from standpoints of both a subject in Plant Geography and Synecology and as natural resources having substantial economic and cultural importance. This is true in particular for the beef cattle industry.

In Oklahoma, Cross Timbers occur on the Central Redbed Plains, the Eastern Sandstone Cuesta Plains (Francaviglia, 2000, p. 23), and northward through the Chautauqua Hills and Osage Questas physiographic provinces which extend through southeast Kansas on which Cross Timbers also developed and remain a climax range type. The older and more familiar names for the last three of these is Sandstone Hills and Chautauqua Hills or, more generally, Sandstone Hills (Fenneman, 1938, ps. 613-614, 616-617, Plate VI).

South of Oklahoma's Red River the major physiographic provinces supporting Cross Timbers are the Redbeds Plains and Commanche Plateau (Fenneman, 1938, Plate VII), or bordering along the Edwards Escarpment and Lampassas Cut Plain of Texas (Fenneman, 1938, Fig. 27, p. 102). South of the Red River the Cross Timbers (ie. the Texas Eastern and Western Cross Timbers) are in the West Gulf Coastal Plain of the Coastal Plain Province (Fenneman, 1938, ps. 100-103). An instructive indication of the close relationship between physiographic province and general or regional plant community (sub-formations) was shown when Fenneman (1938) labeled on his plates and figures both the Eastern Cross Timbers and Western Cross Timbers.

The Cross Timbers is (are) one of several ecotones or transitions between the deciduous forest formation of eastern North America and the climax tallgrass (Andropogon-Sorgastrum) prairie to the west. The definitive authority of the eastern deciduous forest remains Lucy Braun who interpreted the Cross Timbers as part of the "forest-prairie transition" of the oak-hickory forest region (Braun, 1950, ps. 177-178). Earlier in the seminal study of Oklahoma vegetation (Bruner1931, ps. 108- 110, 115-116, 129, 142-148) treated the Cross Timbers as an "oak-hickory savanna". Dyksterhuis (1957, p. 437) applied savanna as a concept and term to the Cross Timbers. More recent descriptions and interpretations retained the savanna designation although Francaviglia (2000, p. 119) concluded that from more detailed accounts (especially one by W.L. Ormsby, Jr) Cross Timbers generally "referred both to a forest with a dense, nearly impenetrable understory as well as to a more open, savanna-type forest with fairly widely spaced oak trees".

Location notice: Most of the climax plant communities of the Cross Timbers is a savanna, but as described in journals and published books by early travelers, teamsters, etc. some of the potential natural vegetation is a nearly impenetrable thicket of scrub oak such as sand post oak (Quercus margarettiae= Q. stellata subsp.margarettiae) and woody vines, especially fiddleleaf green-brier (Smilax bona-nox).

This climax vegetation can be interpreted either as a scrub or shrubland range type or, alternatively, as a dwarf forest cover type. Such a sand post oak-fiddleleaf green-brier community (habitat type) was presented under the title Miscellaneous for both forest and shrubland biomes.

5. The Cross Timbers rangeland cover type (SRM 731 & 732) varies from the open, park-like savanna seen here to dense thickets more scrub-like than wooodland in physiogonomy. The original and still definitive ecological treatment of the Western Cross Timbers vegetation is that of Dyksterhuis (1948) who recognized six “major vegetal types or plant communities” (four types based on floristics) within the overall belt of this range type. Shown here is the “vegetal type” Dyksterhuis (1948, p. 341) described as “the open prairie type of mature Reddish Prairie soils with gentle relief”. The predominance of grassland appearance in this photograph is likely due to long-term grazing by sheep and probably goats. There is an obvious high browse line on the trees (high-lining), but overgrazing of the understory is not apparent because the community is primarily silver bluestem, the dominant species and an increaser, and little bluestem and Indiangrass, decreasers. Dyksterhuis (1948, p. 355) recognized silver bluestem as the “warm-season mid grass dominant of the grazing disclimax”. Invader grass species like purple and/or Wright’s threeawn (Aristida purpurea= A. wrightii or both are varieties of A. purpurea) are present in small amounts. This is late spring and the tallgrass species have not elongated the culms fully and inflorescences are still in the boot. The cool-season increaser, Texas wintergrass, is common and conspicuous in winter and spring and adds seasonal variation to this diverse range community. There are no shrubs, none. The dominant tree is post oak; Virginia or southern live oak (Quercus virginiana var. fusiformis) is the limited associate. There are no blackjacks, mesquites or pecans. Close to pristine overall. Rolling Prairie range site; range condition class is Good.

Eastland County, Texas. Vernal aspect, May. No exact FRES, but an ecotone between FRES No. 15 (Oak-Hickory Forest Ecosystem) and FRES No. 39 (Prairie Ecosystem), but more K-75 (Cross Timbers) than K-73 (Mosaic of Bluestem Prairie [K-66] and Oak-Hickory Forest [K-91]). SRM 732 (Cross Timbers, Texas; Little Bluestem- Post Oak). Cross Timbers- Western Cross Timbers Ecoregion, 29c (Griffith et al., 2004).

6. Oklahoma Cross Timbers- This is a textbook view of Cross Timbers in the Osage Questa province in Excellent range condition class. This is a Shallow Savannah range site dominated by the Four Horsemen of the Prairies with tall dropseed, purpletop (Tridens flavus), beaked panicum, and sand lovegrass as associates. Blackjack and post oaks are the dominat trees with hickory and American and red elm scattered.

"As I sit here today many miles I am away,
from the place I rode my pony through the draw;
Where the oak and blackjack trees
kiss the playful prairie breeze,
in the Oklahoma hills where I was born."

---- Oklahoma Hills, Woody Guthrie

This is in the interior of the actual Cross Timbers which resembles the famed Prairie Peninsula of Transeau (1935). It resembles a mosaic of tallgrass bluestem-Indiangrass prairie and oak-hickory forest, but is actually a vegetation type all it's own.

Osage County, Oklahoma. September. Estival aspect; peak standing crop. FRES No. 15 (Oak-Hickory Forest Ecosystem), K-75 (Cross Timbers). SRM 731 (Cross Timbers, Oklahoma). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Cross Timbers- Northern Cross Timbers Ecoregion, 29a (Woods et al., 2005).

7. Detailed interior view of post oak-dominated and brush understory form of Cross Timbers (Oklahoma)- This is a three-layered (-storied) Cross Timbers community growing in the heart of the Sandstone Hills. The understorey consisted of two layers. The taller layer (hence middle storey between tree canopy and lower shrub storey) consisted of redbud and cedar elm as shrubs or lower-stature trees entangled with vines (lianas) of greenbriar and grape. The lowest storey was dominated by the short, colony forming shrub generally known as buckbrush (Symphoricarpos orbiculatus). Seedlings and saplings of post oak were components of both these layers, hence of all layers of this vegetation. The most common herbaceous species was the rather infrequent coneflower commonly called blackeyed susan (Rudbeckia hirta).

This local Cross Timbers community had been excluded from burning for a number of years. Consequently it developed this multi-storied architecture of woody plants instead of the natural, open understorey comprised primarily of herbaceous species. The vegetation seen here should be compared to the local Cross Timbers community shown in the next three photographs. The latter had been subjected to some recent surface fire(s) and had the herbaceous understorey characteristic of the climax Cross Timbers savanna.

Lincoln County, Oklahoma. May (vernal aspect). FRES No. 15 (Oak-Hickory Woodland Ecosystem), K- 72 (Cross Timbers). SRM 731 (Cross Timbers, Oklahoma). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Shallow Savanna range site. Cross Timbers- Northern Cross Timbers Ecoregion, 29a (Woods et al., 2005).

8. Interior view of Oklahoma Cross Timbers with open herbaceous understorey — This is an example of a well-developed (and well-managed) climax Cross Timbers community with post oak and blackjack oak co-dominant and black hickory (Carya texana) the associate tree species. Often one or the other of these two oak species is the dominat of a Cross Timbers stand with the other species being either the associate or, sometimes, infrequent to absent. This condition is manifested as either a post oak or blackjack oak form or subtype. Bruner (1931, ps. 143-146) explained that blackjack was better adapted to drier, sandier, and generally less favorable habitats than post oak. He reported that blackjack was generally an inferior competitor with more tolerant, mesic species but that a mixture of both of these oaks was "…characteristic where the association [oak-hickory savanna] is well developed" (Bruner, 1931, ps. 146-147). In this section of his monograph Bruner (1931, esp. p. 147) listed the third dominant as Hicoria buckleyi (black or Buckley's hickory formerly named C. buckleyi and, earlier, as H. buckleyi and now identified as C. texana) which he found to be more common on more favorable local habitats especially those with soils of higher clay content and on north or east slopes (ie. more mesic micro-sites).

All three of the dominants of the oak-hickory savanna association were well-represented (common and widely distributed) in the stand shown in this and the next two slides. These three photographs caught the Oklahoma Cross Timbers at ultimate development. These examples, complete with the "clear" herbaceous understorey maintained by fire, showed this range cover type at its zenith.Vegetation seen in these three slides should be compared back to the immediately preceding slide which showed vegetation of unburnt Cross Timbers on similar habitat (the same range site). Dominant herbaceous species was upland switchgrass, which was consistent with this more mesic site as indicated by abundance of black hickory. Canada wildrye appeared to be the second most common grass (and, in fact, was a local dominant on some micro-sites) while the associate herb was the forb, black- (= brown-) eyed susan, that appeared very conspicuous in this view.

The foremost tree was post oak while the other two large trees to the right of the post oak were blackjacks.

Lincoln County, Oklahoma. May (vernal aspect). FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Cross Timbers). SRM 731 (Cross Timbers, Oklahoma). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Shallow Savanna range site with north aspect. Cross Timbers- Northern Cross Timbers Ecoregion, 29a (Woods et al., 2005).

9. Interior view of Cross Timbers in Sandstone Hills of central Oklahoma- This is the second of three photographs that presented a detailed view inside of a well-developed community of Oklahoma Cross Timbers that approached species composition of the climax vegetation.. Dominant tree species were post and blackjack oaks with black hickory as the associate tree species. The tree in right foreground was a mature (though not ancient) black hickory. The bark, shape of bole, and leaves were representative of this species. Trees in background were primarily young post oaks. Conspicuous forb was black-eyed susan. Switchgrass, Canada wildrye, and beaked panicgrass were dominant grasses in roughly that order. An unidentified sedge (Carex) species was also present. Species present were primarily those of the climax vegetation, but their relative proportions were a departure from the composition of the climax savanna. "Guestimated" percentages (based on rough estimates of cover, density, etc.) of herbaceous species were reduced while those of the woody species were increased over that described for pre-Columbian vegetation (hypothetical reconstructions based on examples of relict vegetation, early journal accounts, succcessional studies, etc. used as the basis of range site descriptions). Relative small size and juvenile age of most trees (eg. those in background) suggested that there were recent increases in tree regeneration and canopy cover most likely due to fire suppression and related human-induced impacts such as periodic overgrazing or vehicular traffic. The presence of black hickory, the most mesic of major Cross Timbers tree species, indicated that this site on a north slope was favorable for growing a dense stand of trees in the unnatural absence of natural, recurrent fire. Note, however, that some fairly recent surface fire(s) had "cleaned up" (to a degree) the understory such that there was an herbaceous understorey rather than the "brush patch" or "tangle" architecture of unburnt Cross Timbers such as that shown two slides above this photograph.

Lincoln County, Oklahoma. May (vernal aspect). FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Cross Timbers). SRM 731 (Cross Timbers, Oklahoma). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Shallow Savanna range site with north aspect. Cross Timbers- Northern Cross Timbers Ecoregion, 29a (Woods et al., 2005).

10. Interior of Cross Timbers in Sandstone Hills of central Oklahoma- This is the last of three slides that showed a typical interior of well-developed Oklahoma Cross Timbers. Vegetation consisted of climax species but not with the climax proportions of those species there having been an increase in tree density and canopy cover with some human disturbances (primarily reduction in natural fire). The Cross Timbers community shown in this and the two slides immediately above had been subjected to some relatively recent fire(s) with the resultant open herbaceous understorey. This interior architecture should be compared to that of unburned Cross Timbers which allowed development of a dense woody understorey (complete with two or three layers of woody plants). An example of this "thicket-like" form of Cross Timbers that results from fire exclusion was presented in the third slide above this one. Even with recent "burning off of the woods" the Cross Timbers vegetation shown in this and the two preceding slides had been fired so infrequently relative to the estimated historic fire regime that the community was more a woodland than a savanna.

Trees in the foreground were blackjack oak (the left-most tree and the two right-most and closest foreground trees) and post oak (two remaining trees; the second on the left and the one behind and to the left of the right-front blackjack). Dominant (and conspicuous) grass was switchgrass with Canada wildrye and beaked panicgrass also prominent. Dominant forb was black-eyed susan.

Lincoln County, Oklahoma. May (vernal aspect). FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Cross Timbers). SRM 731 (Cross Timbers, Oklahoma). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Shallow Savanna range site with north aspect. Cross Timbers- Northern Cross Timbers Ecoregion, 29a (Woods et al., 2005).

11. Scrub blackjack oak form of Cross Timbers- Blackjack oak dominates the Cross Timbers on the harsher (drier, shallower) sites. This was explained above under slides of Oklahoma Cross Timbers using descriptions cited from the classic, definitive works (eg. Bruner, 1931, Francaviglia, 2000). Shown here was a consociation of the scrub or shrub form of blackjack. This can be compared to the tree form of this species shown in the immediately preceding and immediately succeeding slides. The blackjacks shown in these slides grew on a north slope and hillcrest of a north slope, respectively, whereas the blackjacks shown here grew on a south slope. It was the same range site (Shallow Savanna) in all slides with the major difference being north- versus south-slope aspect. However, a most interesting phenomenon and comparison between these habitats was that upland switchgrass was the dominant understorey species on all three! The unmistakable leaves and panicles of switchgrass were prominent in the left foreground of the present slide. Switchgrass grew only at edges of and in interspersed openings among the larger thickets of blackjack. The hard, undecomposed leaves that had fallen from the blackjacks formed mats or mulches around bases of the shrubs that were from two to six inches in depth. Leaf litter combined with the shade from green leaves on the oaks effectively excluded all other plant species from the blackjack thickets. Such layering of blackjack leaves from several previous seasons was ready fuel for fire. Any such fire would scourch the blackjacks to the point of top-killing them resulting in more swithcgrass and smaller blackjacks (following regrowth) with less woody cover. The unnaturally high proportion of blackjack cover seen here is a disturbance climax brought about by man's elimination or, at least, reduction of natural fire regimes.

Lincoln County, Oklahoma. July (estival aspect). FRES No. 15 (Oak-Hickory Woodland Ecosytem), K-72 (Cross Timbers). SRM 731 (Cross Timbers, Oklahoma). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Shallow Savanna range site on south slope. Cross Timbers- Northern Cross Timbers Ecoregion, 29a (Woods et al., 2005).

12. Blackjack oak-dominated Cross Timbers in Sandstone Hills of central Oklahoma- This is the blackjack oak form or phase of Cross Timbers savanna with unusually high recruitment of oak and consequent exclusion of herbaceous species. This single-species stand (consociation) of blackjack oak developed on a rocky hilltop on the crest of a north slope. All age classes of blackjack were present with older oaks growing into the tree form rather than the shrub or scrub oak form shown in the immediately preceding slide. The older blackjacks were not as large as those photographed growing on north slopes with post oaks and black hickory, but the local habitat viewed here was more favorable than the shallow soil and south slope that restricted development to the scrub thicket formshown in the preceding slide. Also, present on this northern aspect hillcrest was a second layer of woody plants that was made up largely of buckbrush. Switchgrass (the dominant grass), little bluestem, Canada wildrye, and broomsedge bluestem were present but extremely sparse in small open spaces scattered among trees. None of these spaces or patches were visible here. An unidentified species each of Carex and of moss (Musci sp.) dominated microsites formed by shade from trees. This was visible in foreground of the view shown here.

Lincoln County, Oklahoma. May (vernal aspect). FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Cross Timbers). SRM 731 (Cross Timbers, Oklahoma). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Shallow Savanna range site on the ridgeline of a north slope. Cross Timbers- Northern Cross Timbers Ecoregion, 29a (Woods et al., 2005).

13. Blackjack oak trees top-killed by intense prescribed fire on tallgrass prairie- This and the following slide were included to show readers the size of blackjack trees that can be top-killed by fire on tallgrass prairie and associated savannahs like the Cross Timbers. Blackjacks over 15 feet in height were top-killed by an intense heading fire set at base of this slope and fueled by the dry matter (necromass) of tallgrass species (big bluestem was dominant with Indiangrass and little bluestem associates) that accumulated from deferment in the previous growing season. The prescribed burn was conducted about six weeks prior to the time of this photograph. It was a hot fire and totally killed all blackjack tissue above ground level.

This was big bluestem-dominated tallgrass prairie (the big bluestem phase or form of tallgrass prairie, bluestem prairie, which is more mesic than the Indiangrass and little bluestem-dominated forms). This form usually is more productive of biomass (higher-yielding) and produces more (perhaps not a lot more) fuel than the less moisture-requiring and generally lower-yielding latter two species. This bluestem prairie on the Osage Questas physiographic sub-province is part of a tallgrass prairie and oak-hickory-tallgrass savanna complex (a mosaic of these general, major communities) that also includes the Flint Hills to the west and the Chautauqua Hills "inserted" inside the Osage Questas. It is the sandstone-derived Chautauqua Hills that precisely speaking are part of the Cross Timbers, but blackjack and post oaks do not rigorously conform to such precise divisions as these which geologists and ecologists delight in delineating. Thus it was that blackjacks had "lite out from where they belong" in the adjoining Cross Timbers and invaded the pristine virgin sod of the bluestem and Indiangrass prairie pastures. Contemporary prairiemen took a lesson from the orally trasmitted knowledge of numerous Indian tribes that had at one time or the other claimed this former magnificent buffalo-elk range and fired the prairie to once more rid it of the woody scurge that would deplete it's forage resource. Cowboy meaning: a roaring up-slope fire "did in" the blasted damn blackjacks and let the grass get the upper hand.

This and the next slide showed beginning— and perhaps not so beginning —students of Range Management how effective prescribed burning can be in maintaining grasslands and savannahs against excessive woody encroachments. Even though these two photographs were of neighboring tallgrass prairie vegetation and are not technically speaking that of Cross Timbers, they illustrated perfectly how fire maintains the "balance" (proper proportions) between woody and herbaceous climax species in the potential natural vegetation of savannas like the Cross Timbers that are neighbors to some of God's greatest fire-maintained grasslands.

Osage County, Oklahoma. May (vernal aspect). RES No. 39 (Prairie Grassland Ecosystem), K-66 (Bluestem Prairie). SRM 710 (Bluestem Prairie) most specifically, but also SRM 601 (Bluestem Prairie) generally. Loamy Prairie range site. Former Chapman-Barnard Ranch, now The Nature Conservancy Tallgrass Prairie Preserve, Flint Hills Ecoregion, 28a (Woods et al., 2005).

14. Blackjack oak trees top-killed on bluestem prairie by prescribed burning- A hot heading fire about six weeks prior to this photograph was used to completely top-kill blackjack oaks that invaded virgin big bluestem-dominated prairie from neighboring Cross Timbers. The bluestem pasture was fired when the blackjacks and grasses were dormant. The typical stimulus-like response of big bluestem and Indiangrass to spring burning was evident in this post-burn view, but the blackjacks also responded with immediate resprounting from stumps and roots. Yes it would take more than one intense "hotter 'n hell" fire to rid this luxuriant range of the invading blackjack oak, but one fire effectively killed or eliminated what was surely two decades or more of oak growth. Prescribed fire but once in four or five years will control blackjack oak to its proportion of species composition in the climax grassland (ie. reduce oak crown cover to levels approximating those of the potential natural vegetation), and make more grass forage for buffalo, elk, beef cattle, etc.and more meat for top-order carnivores such as man.

Note height of sprouts of both blackjack oak and smooth sumac (the latter along extreme right margin of slide). Observe also the absence of grass under blackjacks in pronounced circular patterns. This latter phenomenon can be extrapolated back to the pattern observed above for the blackjack shrub thickets on south slopes in the Sandstone Hills Cross Timbers (three slides immediately above this slide).

Osage County, Oklahoma. May (vernal aspect). Fres No. 39 (Prairie Grassland Ecosystem), K-66 (Bluestem Prairie). SRM 710 (Bluestem Prairie) specifically and SRM 601 (Bluestem Prairie) generally. Loamy Prairie range site. These last two slides showed how cover and density of woody plants could be (was, under natural conditions) reduced or prevented from becoming excessive in maintenance of climax savannas like the Cross Timbers that were conterminous with the bluestem prairie form of tallgrass prairie. Chapman Barnard Ranch, now The Nature Conservancy Tallgrass Prairie Preserve. Flint Hills Ecoregion, 28a (Woods et al., 2005).

Cross Timbers Diversity- Any range type--by definition and the very nature of it's comparatively large spatial dimension and, though considerably less determinative, differences in temporal scale-- has meaningful (important) variation within it. Such diversity stems from differences in geology, soils, topography, climate and weather, age (evolutionary, successional, etc.), sources of organisms, and, of course, human impact. The various distinctive expressions in the range plant and animal community at large spatial scale within a range type constitute units known variously as variants, subtypes or forms of that range type . Of course, the range site is the smallest, most distinctive unit or heirarchial level of range that has a unique range plant community as determined by a combination of soil, physiography, elevation, exposure, etc. The range site then is the smallest recurring biotic-geologic-edaphic-climatic-(and so on) unit within a given range type or, more specifically, within range subtypes or variants. Thus there are numerous variants or subtypes of a range cover type and within these cover type variants there are range sites. Thus there are two major levels of ecological hierarchy within a range type: 1) range subtype or range type variant and 2) range site.

The Cross Timbers as a range cover type (Society for Range Management number 731) includes several variants and is itself a subunit of the oak-hickory-tallgrass savanna (Society of American Foresters number 40). Some of these variants or subtypes are better known than others due largely to being of wider geographic distribution and/or more uniquely distinctive physiogonomy, species composition, structure, and so forth. For example, one of the most obvious of these differences in Cross Timbers variants is the West Cross Timbers versus East Cross Timbers in northern Texas. Even within such readily recognizable variants there are differences. These different forms of climax vegetation may be at the hierarchial level (unit) of range site, the lowest or smallest unit, or they may be at the next highest (larger) unit of variant within a variant. A very pronounced case of this latter (variant within a variant) is the Palo Pinto form of West Cross Timbers.

Cross Timbers, a climax tallgrass-oak-hickory savanna, can be of different variants or range sites even on the same soil series if other environmental features are different (eg. slopes, aspects, latitude, elevation, slightly different climate). A case in point is Cross Timbers on the Stephenville soil series (fine-loamy silceous, thermic ultic haplustalf). Cross Timbers vegetation on Stephenville soil in Wilson County, Kansas (southcentral Kansas) includes bristly green-briar (Smilax hispida= S. tamnoides), black oak (Quercus borealis= Q. rubra), and black or Texas hickory (Carya texana), native woody species, and sericea lespedeza (Lespedeza cuneata= S. sericea), a naturalized weedy legume, that are absent from Cross Timbers on Stephenville soil in Erath County, Texas) which is roughly 450 miles southward and where the greenbriar species is S. bona-nox and it and Texas or Spanish oak (Q. texana= Q. buckleyi= Q. shumardii var. microcarpa) are native woody plants that are absent from the Kansas Cross Timbers on the Stephenville series.

15. Foundation of Kansas Cross Timbers- Large outcropping of Fall River sandstone at northern edge of the Cross Timbers range type. Blackjack oak was the dominant tree (and woody) species and switchgrass the dominant herbaceous species. The other major grass was poverty oaktgrass (Danthonia spicata) which was growing over the face of the sandstone outcrop. The most abundant forb was the natrualized, weedy (extremely invasive) perennial legume, sericea lespedeza (Lespedeza cuneata; formerely and basis of common name, S. sericea). Shrub species included smooth sumac (Rhus glabra), wild plum (Prunus americana), and prickly ash (Zanthoxylum americanum). Eastern red cedar was invading this range plant community which was certain evidence of inadequate burning.

Wilson County, Kansas, Mid-July (estival aspect). FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Cross Timbers). SRM 731 (Cross Timbers, Oklahoma [although this was southern Kansas]). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Shallow Savanna range site. Central Oklahoma/Texas Plains- Cross Timbers Ecoregion 29a (Chapman et al., 2001).

16. Where tallgrass prairie and oak-hickory forest meet- At its northern extension the Cross Timbers range type wedges between two major forms of tallgrass prairie, the Flint Hills (to the west) and the Osage Cuestas (to the east). Almost all of the Cross Timbers are in the present states of Oklahoma and Texas with Kansas getting only the penetrating point of this savanna vegetation. The Cross Timbers is a "botanical island" ( though a rather large) and the westernmost area of the oak-hickory forest region or association. The closest botanical affinity of Cross Timbers from standpoint of tree species is the Ozark Plateau which, again, Kansas laid claim to but a fraction of (an even tinier part of the Springfield Plateau vegetation than of Cross Timbers). Almost all grass, forb, and shrub species of the Cross Timbers are held in "common trust" with the oak-hickory forest and tallgrass prairie.

Major tree species in this "photographic sample" of Kansas Cross Timbers were (in this relative order of dominance as a general function of crown cover, tree density, frequency, and sexual reproduction): blackjack oak, post oak, black oak, chinquapin (chinkapin) oak (Quercus muhlenbergia), black or Texas hickory (Carya texana). Most common shrubs were blackberry (Rubus spp.), bristly green-briar (Smilax hispida= S. tamnoides= S. tamnoides var. hispida), and fox grape (Vitis vulpina). Grass species (again in approximate order of cover and apparent abundance) were: Canada wildrye, switchgrass, little bluestem, big bluestem, Indiangrass, purpletop, broomsedge bluestem, and sideoats grama. Forbs included a Solidago species that the author could not identify in its vegetative stages and the highly invasive, natrualized, agronomic forage, sericea lespedeza.

There was more than enough reproduction of all oak species, especially of the dominant blackjack oak. In fact, in continued absence of fire this range vegetation was well on its way to becoming a closed canopy forest form of Cross Timbers. The good news was that, given Jayhawkers love of firing the range coupled with enough hillbilly pyromaniacs, this "woods" would undoubtedly be burnt off before it developed into much more of a forest form than it already was. Unfortunately, some Cross Timbers range in an adjacent locality had already grown too thick with blackjack and post oaks (covered shortly below).

Wilson County, Kansas, Mid-July (estival aspect). FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Cross Timbers). SRM 731 (Cross Timbers, Oklahoma [although this was southern Kansas]). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Savanna range site. Central Oklahoma/Texas Plains- Cross Timbers Ecoregion 29a (Chapman et al., 2001).

17. Not exactly the sterotype of Kansas- Interior of Crosss Timbers range toward the northernmost extreme of this range type. Dominants--by virtue of crown (canopy) cover, size of plants, and defining physiogonomy--were tree species (in this relative order): blackjack oak, post oak, black oak, chinquapin oak and black or Texas hickory. This "photographic sample" Cross Timbers range vegetation was the more open form of this type (in contrast, for instance, to the more closed canopy form shown immediately below).

There was considerable herbaceous development in this "open" form (more openings in the canopy layer; tree crowns farther apart) of Cross Timbers. Consistent with this well-developed herbaceous understorey was the presence of numerous species of grasses and forbs. Major grasses were Canada wildrye, switchgrass, big bluestem, little bluestem Indiangrass, purpletop, broomsedge bluestem, and sideoats grama. The major (and, certainly, most conspicuous) forbs were slender mountain-mint (Pycnanthemum tenuifolium) and smooth oxeye (Heliopsis helianthoides). Most common (important) shrubs were smooth sumac, blackberry, bristly green-briar, and fox grape.

Wilson County, Kansas, Mid-July (estival aspect). FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Cross Timbers). SRM 731 (Cross Timbers, Oklahoma [although this was southern Kansas]). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Savanna range site. Central Oklahoma/Texas Plains- Cross Timbers Ecoregion 29a (Chapman et al., 2001).

18. Interior of Kansas Cross Timbers- Blackjack oak scrub forest-tallgrass prairie savanna with dominance by blackjack oak and post oak the associate woody species. Black oak was also well-represented. Most of the oak reproduction was of blakcjack oak. Dominant shrub species was eastern redbud (Cercis canadensis) that was present mostly as large seedlings to small saplings. Dominant herbaceous species was the cool-season grass, Canada wildrye. The main forb was a Solidago species that the author could not identify in its vegetative (pre-bloom) stage.

Range vegetation in these two photographs had greater tree density and crown cover than in preceding views of Kansas Cross Timbers. It was the more "closed" (closer to closed canopy) form or expression of Cross Timbers. Consequently, herbaceous layers were less developed and there were fewer herbaceous species. Also, physiogonomy was correspondingly different from the more open or savannah form of Cross Timbers.

It was not known when this range vegetation had last been subjected to fire of any kind, but it had obviously been quite a while (too damn long for "shore").

Wilson County, Kansas, Mid-July (estival aspect). FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Cross Timbers). SRM 731 (Cross Timbers, Oklahoma [although this was southern Kansas]). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Savanna range site. Central Oklahoma/Texas Plains- Cross Timbers Ecoregion 29a (Chapman et al., 2001).

"I shall not easily forget the mortal toil, the the vexations of flesh and spirit, that we
underwent occasionaly, in our wanderings through the Cross Timber. It was like
struggling through forests of cast iron" (Irving, 1835, p. 186).

19. The Texas West Cross Timbers- This is the brush or thicket form of the Cross Timbers. It is the kind that Washington Irving must have had to pass through when he described the Cross Timbers as “forest of cast iron”. It is the “vegetal type” named and described by Dyksterhuis (1948) as the “Quercus-Smilax type” on sandy Red and Yellow Podzolic soils of gentle to moderate slope. Dyksterhuis (1948, p. 341) found the mostcommon grass to be fringeleaf paspalum (Paspalum ciliatifolium). In this parcel sand dropseed (Sporobolus cryptandrus) was the clear dominant grass, but silver and little bluestem, sideoats and hairy grama, common grassbur (Cenchrus incertus), tumblegrass (Schedonnardus paniculatus), purpletop, Johnsongrass (Sorghum halepense), and tumble windmillgrass (Chloris verticillata) were all common (and most are visible in the slide). Saw greenbriar (Smilax bonanox) is clearly the dominant shrub (not the place for a trail ride) followed by the associate shrub, smooth sumac (Rhus glabra), and scattered chittamwood or gum-elastic (Bumelia lanuginosa). Tree species in order of dominance: post oak and blackjack oak (dominants), live oak (an infrequent associate), and mesquite (rare).

As a University of Nebraska-produced Ph. D. (a student of John E. Weaver and disciple of F.E. Clements) E.J. Dyksterhuis (1948, ps. 372-374) generally regarded the potential vegetation of the Westerrn Cross Timbers as a climatic climax of oak-little bluestem and Indiangrass understory savannah. That form was shown in some of the preceding slides. Dyksterhuis was unsure how to interprete the Cross Timbers vegetation on Red and Yellow Podzolic soils (p. 373). It seemed logical (rather undeniable in fact) to the current author that such vegetation was a mixed understory of shrubs and grasses (tall, mid- and short grasses) with a woodland-like canopy of scattered oaks of smaller mature size than those of grassland savannas. This seemed the only rational explanation given that the Cross Timbers oak scrub type known as Sand Rough (see under Shrubland slides) exist as postclimax at one extreme of dominance by woody species while the woodland form of savanna exist at the extreme of least coverage of woody plants. Furthermore this must be combined with the historic accounts of tangled woody undergrowth prior to overgrazing by livestock (ie. in the virgin vegetation).

20. Forest form of Western Cross Timbers (Texas)- Exterior view of the forest-like expression of post oak-dominated Western Cross Timbers. These large post oaks have a well-developed tree-form resulting in a physiogonomy and architecture that resembled an actual forest or, at least, a woodland rather than the savanna form or physiogonomic expression more common of the Cross Timbers. Equally, if not more importantly, the trees were large (by post oak standards) and not distinguished by twisted and broken limbs. Trees with these features (ie. "normal trees") stood in rather stark contrast to the stunted or more-or-less depauperate form of post and blackjack oaks that are thought of as more characteristic of old-growth specimens. In one of the earliest reports on the Cross Timbers of Oklahoma Bruner (1931) described the trees as "…a scrubby growth of oaks…" (p. 142). Bruner (1931, p.146) presented a photograph of a stunted post oak and described it as "showing the typical growth-form in the savanna". He wrote that on uplands post oak was "…always small or of moderate stature". Dyksterhuis (1948, p.333) quoted from a report in 1841 that described the trees as "principally small gnarled" and Dyksterhuis (1948, p. 337) remarked that "timber of log-size" was at time of his monograph restricted to flood plains. Diggs et al. (1999, ps. 46-48, Fig. 20, p. 49) and Francaviglia (2000, ps.38-40) described the general shape and dimunitive size of post and blackjack oaks.

The trees shown here were massive by Cross Timbers standards and were included to enable viewers to appreciate the size and age to which trees of this savanna type can grow. Viewers should take careful note of the relative great height at which limbs come off the bole. Dyksterhuis (1948, p. 333) wrote that the "oldest ranchers" he spoke with recalled that fires in the tallgrass understory of Cross Timbers "burned the limbs off the trees to a height that enabled a man on horseback to ride beneath their crowns". Viewers could also note to advantage the horizonal orientation of limbs (and even secondary branches) on these ancient post oaks. Such morphological features clearly indicated the absence of a competing woody understory throughout most of the long lives of these patriarchs. Recent fires have not run through this old stand of monarchs and a woody understory developed instead of the climax herbaceous understory dominated by little bluestem and Indiangrass. Most tragically, an understory of young Ashe or blueberry cedar has formed under the mighty post oaks due to the the "toilet habits" of birds that perched in the canopy and fire exclusion practices (or the neglect of prescribed burning) of contemporary agricultural man. Blueberry juniper is a nonsprouting species. In the days before man, and later when the red man had the Cross Timbers to himself, natural fires and/or those set in aboriginal wisdom would have taken proper care of the bloody invading blueberry. Now this coniferous pest can grow to heights that will form a fire staircase and generate such intense heat as to threaten the robust and ancient post oaks.

The species present in this outer or physiogonomic view were given immediately below with the next slide which is an "inside look" at this same local community.

FRES No. 15. Oak-Hickory Woodland Ecosystem), K-75 (Cross Timbers). SRM 732 (Cross Timbers, Texas; Little Bluestem-Post Oak). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Sandy range site; not climax state but physiogonomy was characteristic. Cross Timbers- Limestone Cut Plain Ecoregion, 29e (Griffith et al., 2004). Tarleton State University Hunewell Ranch. Erath County, Texas. May (vernal aspect).

21. Interior of the forest form of Western Cross Timbers (Texas)- A view inside the post oak- dominated forest form of the Western Cross Timbers. Cedar elm (Ulmus crassifolia) was the associate tree species with red mulberry (Morus rubra) running a "close second". Some sugarberry (Celtis laevigata) was also present. Blackjack oak was absent from this local community, but there were occasional (scattered) large specimens of Texas red oak, also known variously as Shumard or Spanish oak, (Quercus shumardii). Dominant understory shrub was Carolina buckthorn or Indian cherry (Rhamnus caroliniana), but in some areas red haw (Viburnum rufidulum) was locally dominant. (The shrub with the extremely crooked trunk at far right foreground is a red haw.) Green briar or, variously catbriar or bullbriar, (Smilax bonanox) formed a layer with leaves extending both below the trunk and above the crown of the Carolina buckthorn, but the latter appeared to exceed the former in cover. Other shrub species included poison oak, redbud, smooth sumac, skunkbush sumac, spring herald, known also as elbow-bush or devil's elbow, (Forestiera pubescens), and chittimwood (Bumelia lanuginose), but these were restricted primarily to edges where Cross Timbers came into contact with the interspersed mosaic of Grand Prairie tallgrass prairie and small openings in the Cross Timbers. Community. Shade from the unnaturally high rate of regeneration of oak, elm, mulberry, and, sometimes even, sugarberry plus greenbriar, buckthorn, and red haw had effectively excluded all but relicts of the climax tallgrass. The dominant tallgrass climax species was little bluestem with Indiangrass, upland switchgrass, and big bluestem the other decreasers that occurred (in approximately that order). Some Canada or nodding wildrye, another decreaser, was present. The most common grass was purpletop, an increaser. Grasses were most common on small local areas in association with shrubs, especially where shrub cover was sparse. Forbs were not common, but the perennial herbaceous species known variously as Louisiana (or Mexican or white) sagebrush or western mugwort (Artemisia ludoviciana var. mexicana) was the major one.

Dykesterhuis (1948, ps. 342-343) characterized this as the Quercus-Smilax type of the Western Cross Timbers. This type with designation based on name of dominant Genus of the canopy and of the woody understorey (a Texas version of habitat type that preceeded that of Daubenmire perhaps?) was not adequate by itself to communicate this community. The same designation also described the vegetative or physiogonomic character of the scrub form (the thicket or the tangle) of Cross Timbers that was shown and discussed earlier. The composition (species make-up, physiogonomy, layering etc.) of this forest form differed substantially from the previously shown and discussed oak-greenbriar subtype. Most importantly, buckthorn and red haw were absent from the scrub or thicket form shown above. Perhaps most diagnostic among differences was that the Texas red (=Spanish or Shumard) oak was a shrub (at best a small tree) form with short stature and multi-trunk morphology in the thicket or tangle form whereas here in the forest form or subtype of Cross Timbers Shumard oak grew in a tree form sometimes exceeding the large post oaks in stature and trunk diameter. For example, the large tree with tall forked bole in right background was a Shumard oak. The oak-greenbriar thicket (scrub) subtype or form had much greater species diversity and development of tree, shrub, and herbaceous layers.

FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Cross Timbers). SRM 372 (Cross Timbers, Texas; Little Bluestem-Post Oak). Cross Timbers- Limestone Cut Plain Ecoregion, 29e (Griffith et al., 2004). Sandy range site in some state of deterioration due to fire suppression and overgraSAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). zing, but the climax species are present though suppressed. Tarleton State University Hunewell Ranch. Erath County;, Texas. May (vernal aspect).

22. Detail view of interior of post oak-dominated forest form or subtype of Western Cross Timbers (Texas)- This photograph showed detail of the local Cross Timbers community shown in the two preceding slides. The two large trees in foreground (left with straight bole and right with large limbs diverging from bole) were post oaks. The two small trees with light-colored bark immediately behind but to right of the widely branching big post oak were red mulberry. The larger background tree on left was post oak and the two smaller trees immediately to right of it were cedar elm. Local understory was all woody and comprised mostly of greenbriar. None of the climax tallgrass understory species were visible within camera range of this photograph, but some shade-stunted specimens of such species as little bluestem, Canada wildrye, Indiangrass, and purpletop were present in this local community.

FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Cross Timbers). SRM 372 (Cross Timbers, Texas; Little Bluestem-Post Oak). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Sandy range site in a state of deterioration due to fire exclusion and overgrazing but possessing climax species that were suppressed by excessive woody cover. Tarleton State University Hunewell Ranch. Erath County, Texas. May (vernal aspect). Cross Timbers- Limestone Cut Plain Ecoregion, 29e (Griffith et al., 2004).

23. Palo Pinto Cross Timbers- Physiogonomy and exterior view of structure of West or Upper Cross Timbers in northcentral Texas that developed on the rougher "breaks" of a cut plain comprised of sandstone outcroppings and shale beds of the Pennsylvanian Period known as the Palo Pinto Country (Diggs et al., 1999, ps. 45-46).country. A mesic east exposure afforded one of the more spectacular examples of Palo Pinto Cross Timbers.

Post oak was the dominant tree species. Other tree species (with status of associate species varying locally) included cedar elm, blackjack oak, Texas ash (Fraxinus texensis= F. americana subsp. texensis). Among shrubs Texas pricklypear (Opuntia englemannii var. lindheimeri= O. lindheimeri) was conspicuous. Major shrubs included skunkbush sumac (Rhus trilobata= R. aromatica) and wild plum (Prunus perhaps gracilis). There were several species of woody vines including (Smilax bona-nox), poison ivy/oak (Rhus toxicendron= Toxicodendron radicans), and Virginia creeper (Parthenocissus quinquefolia).

Major grasses included little bluestem, silver bluestem, Arizonia cottontop (Triachne californica), green sprangletop (Leptochloa dubia), hooded windmillgrass (Chloris cuculata), white tridens (Tridens albescens), King Ranch bluestem (A. ishaemum), and purpletop (Tridens flavus). Forbs were of no consequence.

Large boulders or fairly massive monoliths were Pennsylvania sandstone.

Palo Pinto County, Texas. Mid-October; early Autumn aspect. FRES No. 15 (Oak-Hickory Woodland Ecosystem). K-75 (Cross Timbers). SRM 732 (Cross Timbers, Texas; Little Bluestem-Post Oak). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Sandstone Hills range site. Cross Timbers- Western Cross Timbers Ecoregion, 29c (Griffith et al., 2004).

24. Crow's view of Palo Pinto Cross Timbers- Palo Pinto variant of West Cross Timbers at scale more revealing of woody species composition. Dominant tree species was post (most of the taller trees in background). In vegetation featured these two photographs there was no single associate woody species. The conspicuous light red or pale orange crown was Texas ash. Cedar elm and blackjack oak were other common tree species. Shrubs included skunkbush sumac, wild plum, Texas pricklypear, and three woody vines (common green-briar, poison oak/ivy, and Virginia creeper). The major herbaceous species were limited but included silver bluestem, little bluestem, green sprangletop, Arizona cottontop, hooded windmillgrass, King Ranch bluestem, and purpletop.

25. Deer's view of Palo Pinto Cross Timbers- This third two-slide set featuring exterior views of Palo Pinto variant of West (Upper) Cross Timbers began with a vertical "slice" as a "photographic dendogram" to show vegetational layers (herbaceous, shrub, tree) and thereby structure of this comparatively dense--essentially a close canopy--of what is more commonly a savanna physiogonomy and structure. Trees in this first slide were post oak (tree at left-center with dead lower limb) with cedar elm to its right. Bush-like woody were mostly young trees of cedar elm followed (in order of abundance) by post oak, blackjack, and Texas ash along with the shrub species, skunkbush sumac. Herbaceous species were mostly little bluestem, King Ranch bluestem, hooded windmillgrass, and green sprangletop. The multi-shoot--most of which were bare-- shrub in extreme lower right corner was a young, resprouted Texas ash.

This shrub-form of Texas ash was presented in more detail (closer distance) in the second of these two photographs (center foreground). Trees behind this multi-stemmed Texas ash were post oak (overall dominant tree species) and cedar elm. Most of the bush-sized/shaped plants in foreground were young trees of cedar elm with some post oak. Herbaceous species were botanically insignificant.

26. Coyote's or cat's view of palo Pinto Cross Timbers- Rock outcrop of Pennsylvania Period sandstone in the distinctive Palo Pinto variant of West (Upper) Cross Timbers. Largest trees (including those missing most of their crowns) were post oak. The associate tree species was cedar elm while Texas ash was the third most common tree. Blackjack oak was present as an incidental tree species. The major shrub was a species of wild plum that was identified (tentatively) as sand plum (Prunus gracilis). The major growth or life form of shrub was liana or woody vine including common green-briar, poison ivy/oak and Virginia creeper. Texas pricklypear was also common.

Major grasses were Arizona cottontop and hooded windmillgrass. Other important grasses were silver bluestem, King Ranch bluestem, white tridens, little bluestem, and green sprangletop.

The "Palo Pinto Country" (Diggs et al., (1999, ps.45-46) form of the West (Upper) Cross Timbers is one of the most distinctive forms of this savann. On more mesic local sites of the overall Sandstone Hills range site featured in this section (especially east and north slopes), tree density is so high that their crowns produce a nearly closed canopy (approaching 100% canopy cover). Actually, this dense canopy is a combination of tree density and a tree morphological form (architecture) with horizontal spreading limbs characteristic of trees growing in savannas or woodlands. This unique, almost-erie shape of trees was presented below (including the immediately following two-slide set). The second of these two slides introduced this phenomenon. Note, for example, the trunk in left-center midground that had completely lost its canopy leaving only a snag with one horizontal lower limb.

27. Cross Timbers jigsaw puzzle- Massive sections of Pennsylvanian Period sandstone that broke and separated along cleavage planes and deformed, disfigured trees in the interior of a stand of Palo Pinto Cross Timbers. The "Palo Pinto Country" form or variant of the West (Upper) Cross Timbers is very distinctive (and scenic, at least by Texas standards). Immense sections or slabs--both vertical and horizontal--of sandstone along with old, comparatively slow-growing, and definitely "broken and battle-scarred" hardwood trees render this tree-dominated range type a photogenic as well as ecological study subject. The dominant tree was post oak with cedar elm generally the associate to be sometimes third to blackjack oak or Texas ash.

The main shrub was a species of plum that could not be positively identified at this vegetative and nonfruit-bearing stage. It was tentatively identified as sand plum (Prunus gracilis). River plum (P. rivularis) was abundant on more mesic habitats farther down this slope. Skunkbush sumac was also common. The three lianas of common green-briar, poison ivy/oak, and Virginia creeper were well-represented. Texas pricklypear was locally super-abundant, especially in certain crevices between slabs of sandstone. The main grasses were Arizona cottontop and hooded windmillgrass. Silver bluestem, little bluestem, and white tridens were also present as was purpletop and green sprangletop though these latter two species were limited to the most moist microhabitats formed by water running off of sandstone. The most common forb in this autumnal society was scarlet spiderling (Boerhavia coccinea).

28. A study of understory- Herbaceous layer of Palo Pinto variant of West Cross Timbers. Cedar elm (tree trunk, first slide) with Arizona cottontop and hooded windmillgrass as the major herbaceous species. The major forb was scarlet spiderling (background of first slide). Slate as a minor parent material was visible in the second of these two photographs. In other local (micro-) environments with more soil water (eg. water runoff from sandstone slabs) silver bluestem, King Ranch bluestem, little bluestem, and white tridens were important species.

29. Cross Timbers and Barrens- Landscape scale view of Western (Upper) Cross Timbers existing as a "patchwork" pattern of woodland and glades or balds. The Cross Timbers and adjacent prairies (delineated variously into such units as Fort Worth, Grand, and Northcentral Prairies) are typically interspersed into a mosaic of vegetation varying from open tallgrass prairie to dense oak-hickory (black hickory and pecan) forests with a savanna form made up of these two extremes plus an open, grassy understory woodland between. A much less common form or expression of vegetation in this "botanical mixture" consist of small glades or balds occuring on hilltops with very shallow soils underlaid by the defining sandstone formations. These sandstone barrens are similar to the chert and dolomite glades interspersed among the oak-hickory forest and tallgrass prairies of the Ozark Plateau several hundred miles eastward (presented below in this Tallgrass Savanna section).

Vegetation shown here was photographed from one such sandstone glade with another such barrens visible in center background. Sandstone balds occurred as vegetational subunits within the overall Sandstone Hills range site presented here and in the following series of photographs taken in or adjacent to Lake Mineral Wells State Park. This was in one of the more distinctive areas of the Cross Timbers delineated by it's rugged, broken topography and exposed sandstone and shale rocks and identified as the "Palo Pinto Country" (Diggs et al, 1999, ps. 22, 45-46). Descriptions of vegetation accompanied those examples.

Parker County, Texas. Early October, but still estival aspect. FRES No. 15 (Oak-Hickory Woodland Ecosystem). K-75 (Cross Timbers). SRM 732 (Cross Timbers, Texas; Little Bluestem-Post Oak). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Sandstone Hills range site. Cross Timbers- Western Cross Timbers Ecoregion, 29c (Griffith et al., 2004).

30. Canyon landform of Cross Timbers and Barrens- Vernal aspect (March) of the same vegetation at same precise location as shown in the immediately preceding photograph except from slightly different angle and at wider lense view. From this vantage point the canyonlands form of the "Palo Pinto Country" Cross Timbers was readily shown. The climax plant community of the "bald" (barrens) atop the characteristic sandstone excarpment in background was shown in detail below. In the present photograph the vegetational mosaic at landscape scale was evident. The view was from one sandstone block photographed across the canyon to another sandstone bloc, each the parent material and lithosol for the local "barrens" or "balds" range site (essentially a larger microsite) within general Sandstone Hills range site. Canyon bottom was a more mesic localized microhabitat favoring cedar elm and Texas ash over the dominant oak species.

The large sparsely foliated tree in center midground was cedar elm as was snag in left front of it. A large Texas ash was immediately to right of large cedar elm. Tree immediately right of Texas ash was also cedar elm. These two species were associates to post oak, the overall dominant species, and to blackjack oak, the dominant vascular plant on the "balds" (shown below).

31. Palo Pinto Cross Timbers- An oblique view (at landscape scale) of vernal (March) vegetation of Western (Upper) Cross Timbers in Palo Pinto geologic area.The sandstone-capped cuesta that formed escarpments was the local range site (microsite) for the Sandstone Barrens across canyon in background and in immediate right foreground. Compare snag here (left-center foreground) and in preceding slide for comparative orientation.

32. Sandstone barrens or balds form of Palo Pinto West Cross Timbers- An outcropping of standstone was surrounded by the dominant blackjack oak with local populations of little bluestem, purpleflower dropseed (Sporobolus clandestinus), purple threeawn (Aristida purpurea complex), purpletop, and Indiangrass depending on xeric conditions of microsites. Parker County, Texas. March, vernal aspect.

33. Sandstone barrens within Western Cross Timbers- A sandstone outcrop was dominated by a cryptogamic community comprised mostly of the gelatinus lichen known as jellyskin (Leptogium tenuissimum). Jellyskin was in dried (dehydrated) state when photographed. Scrub (shrub)-form individuals of blackjack oak "ringed" the rock outcrop.There was little in way of understorey beneath blackjacks.General range site was Sandstone Hills. Parker County, Texas. Vernal aspect (March).

34. Sandstone bald form of Western Cross Timbers- Outcrops of sandstone with interspersed narrow strips of shallow soil surrounded by larger local habitats of less shallow soil constituted microsites that made up a bald or barrens expression of Western Cross Timbers. The dehydrated state of jellyskin lichen covered the sandstone outcrops while apparentedly stunted (dwarf-like) individual plants of little bluestem, purpleflower dropseed, and purple threeawn grew on the inter-rock spaces. Soils of slightly greater depth supported scrub blackjack oaks. Overall range site was Sandstone Hills. Parker County, Texas. Vernal aspect (March).

35. Sandstone glade in Western Cross Timbers- The rugged terrain and harsh nature of the "Palo Pinto Country" West Cross Timbers included local sites (larger microsites) with soils that were somewhat better developed (apparently older) than the rock outcrops responsible for the sandstone barrens vegetation shown in the three immediately preceding photographs. Vegetation in this photograph was conterminus with the plant community (ies) seen in these preceding slides.

This vegetation was climax (in the virgin state) except for woody species that were invading due to absence of fire (fire suppression) on this Texas state park. Fire was a natural component of the climate that contributed greatly to development and maintenance of the Cross Timbers. Woody invaders in this photograph included chittamwood, gum-elastic, or gum bumelia (Bumelia lanuginosa); greenbriar; netleaf hackberry or sugarberry (Celtis reticulata= C. laevigata var. reticulata), redberry cedar or redberry juniper (Juniperus pinchotii); and blueberry cedar or ash juniper (J. ashei). Dominant herbaceous species were little bluestem, sideoats grama, and purpletop. Both woody and gramineous species are native and part of the climax or potential natural vegetation, but the unnatural increase of shrubs and trees was obviously primarily a result of elimination (at least great reduction) of natural fire regimes. Presence (and relatively large populations) of climax dominants (decreasers like little bluestem) coupled with absence of any appreciable component of herbaceous invaders (eg. purple threeawn) or hardly even increasers (eg. purple dropseed) was evidence against current, or even recent, overgrazing. Nonetheless, abnormal increase (invasion) by woody plants was causing on-going range retrogression. Underburning was a principal cause of range depletion.

Parker County, Texas. March (vernal aspect).

Next slide, please.

36. Overgrazed sandstone glade- The vegetation shown here was on private property contiguous with that seen in the immediately preceding photograph. The plant community seen in this slide was being (or had very recently been) overgrazed. Prolonged or longterm overuse had resulted in depletion of the more palatable little bluestem, purpletop, and sideoats grama and commensurate invasion by purple threeawn (the conspicuous tufts of bunchgrass) and increases in purpleflower droopseed (predominate plant among clumps of threeawn).

Invasion of the same woody species as in the preceding slide was evident along edges of the glade as an advancing line of young shrubs that was reducing the area of the herbaceous plant community. Fire cessation was also a factor in this invasion, but in addition to underburning overgrazing was an agent of retrogression that induced range depletion in this instance.

Parker County, Texas. March (vernal aspect).

In contrast to the localized examples of depleted Cross Timbers (especially glades portions) there were conterminus locations on Lake Mineral Wells State Park remaining in climax vegetation.

37. Climax sandstone glade in Western Cross Timbers- Two views of a sandstone glade in excellent range condition situated among adjacent tracts of blackjack oak-dominated woodland characteristic of Western (Upper) Cross Timbers. This vegetation was on a hilltop portion of Cross Timbers having more of an open woodland physiogonomy that had a "tangled" understorey consisting of a woody layer of shrubs dominated by young (immature) blackjack and also including young post oak, cedar elm, sugarberry or netleaf hackberry, and such shurb species as saw greenbriar, winged sumac (Rhus copallinum var latifolia), skunkbush sumac, and chittamwood, and an herbaceous layer dominated by little bluestem.

Woody species were noticably less abundant than on adjacent glades shown above including the one that had been been subjected to recent or current overgrazing.

Parts of the sandstone balds or barrens were devoid of woody species (especially the glade form) and had a more species-rich herbaceous community. Little bluestem was the most abundant species but there was not an apparent dominant. The other common grass species on the balds were: green sprangletop (Leptochloa dubia), sand lovegrass (Eragrostis trichoides), and sideoats grama on the shallower microsites in central portions of the glade and tall dropseed (Sporbolus asper) , Texas wintergrass (Stipa leucotricha), purpletop, Scribner's panicgrass (Panicum scribnerianum), Canada wildrye, and wood oats (Uniola latifolia= Chasmanthium latifolium) along perimeter of the glade and beneath or otherwise in shade of trees. The conspicuously dominant forb was slender bushpea or slender lespedeza (Lespedeza virginica).

Lake Mineral Wells State Park, Parker County, Texas. Early October, but still estival aspect. FRES No. 15 (Oak-Hickory Woodland Ecosystem). K-75 (Cross Timbers). SRM 732 (Cross Timbers, Texas; Little Bluestem-Post Oak). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Sandstone Hills range site. Cross Timbers- Western Cross Timbers Ecoregion, 29e (Griffith et al., 2004).

38. Shown below was a series of photographs of Western Cross Timbers in relict or near relict climax condition. The sequence began with an exterior view and consecutive photographs showed progressively more interior views of relatively undisturbed old growth Cross Timbers vegetation. Exclusion of fire by policy and action of a state government agency allowed unnatural excessive development of woody species in the understorey with concomittant decline in the herbaceous component (primarily of little bluestem, the dominant, and also of other grasses such as purpletop, the associate herbceous species, sideoats grama, wood oats, tall dropseed, Canada or nodding wildrye, Texas wintergrass, and even small amounts of big bluestem and Indiangrass).

Parker County, Texas (Lake Mineral Wells State Park unless otherwise designated). FRES No. 15 (Oak-Hickory Ecosystem). K-75 (Cross Timbers). SRM 732 (Cross Timbers, Texas; Little Bluestem-Post Oak). Sandstone Hills range site, including sandstone barrens as local habitat or microsite. Western Cross Timbers Ecoregion, 29e (Griffith et al., 2004).

38A. Composite view of Western Cross Timbers community- An exterior perspective of a virgin stand of post oak-dominated Cross Timbers with a rich diversity of species in all vegetational layers. The foreground was edge of a small opening or glade dominated by little bluestem accompanied by purpletop, wood oats, tall dropseed, Scribner's panicgrass, with traces of big bluestem and Indiangrass in lower (more mesic) microsites at far right foreground. Englemann or Lindheimer (sometimes Texas or nopal) pricklypear (Opuntia engelmannii var. lindheimeri) was conspicuous in the glade (left-center foreground). Most apparent forb was goldenrod (Solidago sp). The young tree or shrub appearing as a bush at far left foreground was blackjack oak showing regeneration of this climax species and illustrating fact that blackjack not post oak tends to dominate on the shallower soil of glades. The large tree with brightly colored leaves at right forefront of tree edge was Texas ash (Fraxinus texensis= F. americana var. texensis). The most common shrub in understorey beneath trees was saw greenbriar. October, but still estival aspect.

38B. Spring in West Cross Timbers composite community- Vernal aspect (March) of the virgin vegetation shown in the immediately preceding photograph. Compare spring coloration of Texas ash at far right foreground with it's autumn coloration in preceding slide.

38C. Stand of old growth post oak-dominated West Cross Timbers- On this sandstone rock outcrop the habit of mature (nearly ancient in relative terms) post oaks created the physiogonomy characteristic of the climax forest form of Cross Timbers. This was an example of the Quercus-Smilax type of the Main Belt described by Dyksterhuis (1948, ps. 340-342). The conspicuous rounded shrub in center foregrounmd was elbow-bush, devil's-elbow, or spring-herald which is typically more common on calecareous soils and among limestone more than sandstone outcrops. Englemann pricklypear was also conspicuously growing at edge of forest and a grass-dominated glade. The understorey inside the forest itlself (beneath trees and not natural clearing or glade) was primarily regenerating post oak and saw greenbriar. Grass species visible at edge of forest and glade (center foreground) was silver bluestem. October, but still estival aspect.

38D. Interior of old growth West Cross Timbers forest community- It was noted at beginning of the Cross Timbers section that this forest or range type was primarily a savanna, but that vegetation was a continuum which varied from grassland with widely scattered (isolated) trees to dense forest and with intermediate types of such canopy cover as to form woodland and savanna forms of the general Cross Timbers cover type. The photographs included in this present series illustrated the forest form. Post oak was the dominant form with blackjack the clear associate. In this slide blackjack was represented by the the second tree trunk from the right and the smaller trunk at far left (leftmost tree). The pronounced horizonal branching of trees that grew in more open woodland was prominent in the limbs of the largest tree, a post oak, in center of slide. The pronounced outward (toward light) curving of the bole (bow-shaped trunk) of the blackjack was another common growth mainifestation of old- growth oaks (in woodland and even savanna forms as well as in forest canopy cover forms).

The understorey was almost exclusively post and some blackjack oak reproduction. Oak leaves formed a forest floor covering interrupted only by standstone rocks. There was essentially no herbaceous undergrowth. Saw breenbriar was sparse and limited to small areas where light could penetrate through the oak canopy to reach the ground surface. Rarely there were other species of woody vines as shown and described in the succeeding photograph and caption.

Lichens growing on the outcropping sandstone rocks formed a layer of vegetation that students should not overlook.

Estival aspect into early October.

38E. Deep inside a Cross Timbers forest on a sandstone outcrop- Narrow spaces of soil among huge sandstone boulders (as large as small houses) provided favorable environments for growth of Cross Timbers trees. Post and blackjack oaks were dominant, but sugarberry or hackberry, Texas ash, and cedar elm were also common. Climbing species were, as shown here, abundant. The thicket-like growth in the left foreground was a mixture of saw greenbriar, supplejack or rattanvine (Berchemia scandens), and poison ivy or oak. Other common vines found variously in the boulder location were Carolina snailseed (Coccus carolinus), Virginia creeper, trumpet-creeper (Campsis radicans), and, infrequently, mustang grape (Vitis mustangensis). This boulder form or expression of a Sandstone Hills range site had so much shade from tree canopies and the vertical rock formation that herbaceous species were more-or-less absent.

October, but still estival aspect.

38F. Not enough fire- Most of the early explorer accounts of the Cross Timbers (including the poetic account of Irving [1835, p. 186] quoted above) and the seminal ecological studies (eg the monograph of Dyksterhuis [1948, p. 333] also cited previously) specifically described presence and/or role of fire in understorey of the Cross Timbers.Fire had obviously been excluded and suppressed-- and obviously for a long time period-- from the state park in which these photographs were taken. Long-term absence of fire, a natural environmental factor, from this Cross Timbers vegetation had allower development of an unnaturally dense woody understorey which had eliminated most of the native herbaceous species except for small microsites. An excample of one such microhabitat was that shown here around an older post oak. Little bluestem, the dominant herb and co-dominant Cross Timbers species (with co-dominant post oak), had persisted on this local site (and others like it). Even here brush (woody species present at unnaturally excesssive cover and population densities) were encroaching on the limited remaining microsites that afforded adequate sunlight and growing spaces. Most of the woody (and excessive) understorey was of post and blackjack oak, but other tree and shrub species were also present. Chief among these was saw greenbriar and chittamwood or bumelia.

Lake Mineral Wells State Park, Parker County, Texas. Early October (and still estival aspect). FRES No. 15 (Oak-Hickory Woodland Ecosystem). K-75 (Cross Timbers). SRM 732 (Cross Timbers, Texas; Little Bluestem- Post Oak). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Sandstone Hills range site. Cross Timbers- Western Cross Timbers Ecoregion, 29c (Griffith et al., 2004).

38G. General co-dominants of the Cross Timbers- Post oak (larger tree with twisted limbs at left background) and blackjack oak ("runt"-- as in scrubby-- trees at right) are the general two dominants of the Cross Timbers. Post oak is far and away the clear dominant with blackjack subordinate so as to be more of an associate, except that blackjack-- often as shrub or small tree more than true arboreus form-- is the exclusnve dominant on the more xeric sites and microsites such as the balds or barrens form of Crosss Timbers.

The shrub layer of Cross Timbers understorey was conspicuous in this photograph due to showy full-bloom phenological stage of creek or hog plum (Prunus rivularis). The two oak species were also in anthesis.

Lake Mineral Wells State Park, Parker County, Texas. March (vernal aspect).

38H. Western Cross Timbers in the spring- Thickets of blooming hog or creek plum highlighted the shrub layer of an understorey beneath the dominant species of post oak (tree with the sparse foliage of new leaves and catkins in right background) and blackjack oak (largest tree in center foreground and branches at far left foreground. Chittamwood or gum-elastic and Carolina buckthorn (Rhamnus caroliniana) were also present as understorey shrubs.

Lake Mineral Wells State Park, Parker County, Texas, March (vernal aspect).

39. One of the key distinguishing (and picutresque) features of the Cross Timbers is the unusual and interesting shape of boles, limbs and branches, crowns, and overall habit or growth form of individual trees of the dominant post and blackjack oaks. These characteristics of distorted tree growth distinguish-- even at first or fleeting glance-- the Cross Timbers expression of the general oak-hickory association or, more precisely, the ecotone between this climax forest type and the tallgrass prairie climax type from the westernmost extension of the actual oak-hickory forest region of Braun (1950, pgs. 35, 162-191). This ultimate authority on the eastern deciduous forest included the Cross Timbers as one part of the "forest-prairie transition" in the oak-hickory region and described the oaks as "usually small and scrubby with broad low crowns" (Braun, 1950, pgs 177-178).

Many, if not most, descriptions of the Cross Timbers characterized the post and blackjack oaks variously as "stunted", "scrubby" or "scrubs", "dwarfish" or "dwarfs", "diminutive", "small-sized", "undersized" "depauperate", etc. More recently-- and perhaps as result of interest in old-growth forests and individual old-growth specimens-- descriptions of relatively small mature trees were more detailed as to specific aspects or parts of small-size and apparent "stunted growth" morphology. From dendroclimatic studies such unique tree habits, crowns, trunk and limb shapes, etc. have been related to harsh physical and chemical features of tree habitat on which slow plant growth rates and distorted tree organs (due perhaps to injury) were associated with old age. Perhaps old age and "abnormal" appearance of trees were results of poor growing conditions such as undernutrition or near constant edaphic drought. Distorted shape and size of organs like boles and limbs might reflect conditions that were below optimum for "normal" growth and reproduction but near maximum for longevity.) Cause and effect relations among the factors of tree age, tree growth, soil conditions, climate (including lightening and fire), browsing, and so forth are not adquately understood.

Diggs et al. (1999, p. 47) described this phenomenon of misshapen, often grotesque, form and diminutive size of old-growth or "ancient" individual trees in the Cross Timbers. These authors cited findings from dendrochronology (tree-ring analysis) and summarized as follows: "Because of the low availability of moisture, rocky or infertile soil, and other factors, the trees of these relict forests, while old, have a slow rate of growth and are of relatively small size... Such old-growth forests or ancient individual trrees can often be located by environmental factors such as steep, rocky, infertile soils or by the appearance of the individual trees... Twisted stems, dead tops and branches, canopies restricted to a few heavy limbs, branch stubs, fire and lightening scars, leaning stems, exposed roots or root collars, and hollow voids are all hints of significtnt age".

Shown below were examples of mature and, quite likely, old if not "ancient" trees growing in the harsh environment of the rugged "Palo Pinto Country" Cross Timbers. Some of these trees had "real character" possessing distinguishing "marks" that obviously resulted from injury (eg. crowns whose tops had been torn off by wind or blown off by lightening, hollows due to rotting following such "amputation", fire scars). Other unusual shapes and sizes appeared to be more the result of inadequate/improper nutrition, including sufficient water.

Readers should bear in mind that this phenomenon of natural bonsai-like growth and aging is not limited to oaks in the Cross Timbers nor to oaks. As shown elsewhere in this publication, dead tops with hollows, spires, cavities and limb loss due to fire or other forces, and relatively small size are characteristics common to old-growth Juniperus trees on pinon-juniper woodland. Neither are such features that are frequent on old trees limited to environments unfavorable for tree growth and survival. Many of the very large (and very old) individuals of the various conifer species that grew to record size, shape, and dimensions (ie. "record", meaning "brag", trees) live on the most favorable, productive sites. The coast redwoods with spire-like dead tops and "goose pen" fire and wind scars are probably most notable among these, but many other examples exist among Sitka spruce, western hemlock, western red cedar, Douglas fir, and even ponderosa pine. It appeared that such scars and marks likely are results of a long life more more than of a hard life.

Whatever the cause-effect relations, many of the Cross Timbers post and blackjack oaks sport natural mutulations that should be the envy of any human specimens vainly flashing tatoos, pierced body parts, streatched necks, embalmed breasts, plasticized penises, corseted abdomens, bustled buttocks, and once-healthy skin now sun-scorched or "fake-baked" to the state of weathered saddle leather or a cancer-eyed cow. The difference between a deformed, hollow old tree and a woman with diamond studs in peirced ears is that the tree has a beauty and dignity all its own. The woman just looks like she was shot with rock salt. Enjoy the examples.

All photographs were taken on Lake Mineral Wells State Park (Parker County, Texas) except the last in the series. March: vernal aspect with oaks at anthesis.

39A. Twisted and turned every which way but loose- Misshapen boles, limbs, and branches of old oaks on a Sandstone Hills range site in Palo Pinto section of Western Cross Timbers gave an aura of mystique in the woods. Twisted and awkwardly bent branches created a unique "design" to the canopy layer of this woodland-like vegetation. All visible trees were post oaks except leaves along left margin which were blackjack oak. The small tree or shrub at base of "blowed top" post oak was Texas ash. Occasional plants of greenbriar formed an interruped or discontinuous woody (shrub) understorey. Tree leaves were so thick as to preclude much of an herbaceous layer in this particular spot such that this was more of the forest form instead of the more typical savanna.

39B. Arborescent goblins- A branching pattern in which primary limbs radiated horizonally from the short trunk with secondary and vertical branching from the primaries gave a hominoid-like appearance to these old Cross Timbers post oaks. Such trees give even the most hardened coon hunter an almost erie feeling as he tromps through these woods under a full moon. One can imagine the spell-like feeling cast on backwoodsmen upon first setting foot in these vast primival savannas.

The featured post oak had lost it's central shoot, including the apically domiant terminal meristem, so that once released from apical dominance secondary branches on the primary limbs grew and developed in neraly vertical planes. The smaller tree with glossy green leaves to left of ole Lost Top was a younger blackjack oak. A young Texas ash was at right base of the topped post oak. Widely scattered shrubs included greenbriar, elbow bush (Foresteria pubescens var. glabrifolia), skunkbush sumac, chittamwood, and Carolina buckthorn. Grasses were absent apparently having been mulched out by accumulations of leaves from the dominant oaks and understorey shrubs as result of unnatural fire exclusion.

"And the gobble-uns'll git ya ef ya Don't Watch Out."--- Little Orphant Annie, James Whitcomb Riley

March: vernal aspect with oaks in full-flower.

39C. Branching pattern in a Cross Timbers post oak following loss of terminal bud and apical dominance- Closer view of the Lost Top post oak shown in the preceding slide. The hollow (cavity) formed by rotting away of dead wood after the injury to tree crown was now easily seen. Texas ash at left base of oak trunk. Note leaf accumulation as result of state park (Texas Parks and Wildlife) policy of fire exclusion.

39D. Crown development of an old post oak subsequent to death of the central and dominant shoot- For a reason (perhaps injury due to lightening, wind, insects, disease) known but to God the main leader of this post oak died such that relieved from dominance (suppression) by apical meristem lower subordinate limbs and branches developed. Result was a lop-sided crown and another hollow-top tree serving as a cozy den for some varmit like a coon or 'possum. Some such tree become hollow clear to the base of their trunk as the innermost trunk, especially heartwood, rots out. This does not affect living tissue (such central heartwood and older sapwood are dead anyway) nor does it typically affect tree health. Such rotting may eventually contribute to loss of tree rigidity and even tree blow-over if and when decomposition proceeds to the root system, but more commonly impact is neglible.

The reason is a feature of physics that is widely know among mechanical engineers: hollow tubes like bird quills, most grass shoot internodes, pipes, airplane wings, and hollow trees are almost as strong as a solid piece of wood, metal, or feather. And they are much less lighter which allows resources to be used for other tissues or materials (eg. those capable of conducting photsynthesis or holding jet fuel) or for more efficient work (easier and more economical to clear ground or a tree branch for flight). It would even be desirable to construct hollow railroad ties, but the technology to do such does not justify the savings in wood.

The well-developed shrub layer of the understorey was comprised mostly of skunkbush sumac and elbow bush with lesser cover of greenbriar.

March: vernal aspect, full bloom phenological stage in oaks.

39E. Wooden arm with a dozen elbows: growth and branching pattern of post oak on sandstone bald- This microhabitat on an outcropping of sandstone was marginal even for a post oak. Result was that this speciman developed a recurrent geniculate (a back-and-forth bending) shape to it's trunk and branches. The more xeric (or less mesic) blackjack oak is typically dominant on such microsites with their shallower, drier soil. Such was the case seen here where scrub (shrub form) blackjacks surrounded the bent, knarled old post oak. These appeared to enjoy each other's company, but they obviously did not invite any herbaceous species to join their party.

Vernal aspect (March, and under a grand but equally rare cobalt-blue Texas sky).

39F. What tales this ole devil tells- An ancient post oak lost the upper portion of it's trunk complete with crown except for one limb which subsequently sent up a vertical branch to assume role of former main shoot and crown though in a much reduced capacity. Yet another picturesque example of the phenomenon of apical dominance. This magnificent old tree was a real survivor-- complete with sexual reproduction and passing on of it's genes in propaguling acorns. In addition to serving as prime real estate for den-dwelling furbearers this gnarled, weatherbeaten, ranking member of the Cross Timbers community never tires of talking about it's accident or "operation". A passing rangeman paused to record the story and pass it along to fellow students of vegetation and admirers of things beautiful.

Palo Pinto County, Texas. March: vernal aspect.

Too much of a good thing or, more correctly said, not enough of a good thing and too much of a bad thing: Presented below were three sets of slides and their captions of a post oak-little bluestem savanna or woodland (depending on personal perspective) five warm-growing seasons after a catastrophic, late winter wildfire top-killed to totally killed mature post oak trees. This fire occurred in Jack County, Texas in March 2011 under ideal conditions (hot, dry, and windy) for a wildfire. Roughly 3000 acres burnt before ther fire was supressed by a combination of agencies including the U. S. Forest Service, Texas Forest Service, and local volunteer fire departments.

Fire effects on range plants and vegetation were about as severe or detrimental as possible for late winter in northcentral Texas. The post oak-little bluestem savanna had decades of accumulated woody fuel. It appeared that a history of heavy grazing to, perhaps, overgrazing had eliminated much of the native grass (little bluestem was predominant on adjoining land--right of way--along US Highway 281) and resulted in a woody understorey apparently dominated by fiddleleaf green-brier (Smilax bona-nox) that grew up into tree crowns. The readily flammable green-brier is a native species, but there was an excessive (un-naturally dense) cover of green-brier that had reached the stage of a brush invasion. Long-term overgrazing with cattle was accompanied with underburning (lack of fire) which together were likely causes of this brush invasion. High density of green-brier shoots extending from ground level to tree crowns formed a fire staircase that under a combination of high tempreatures, high winds, and low humidity resulted in top-kill of almost all post oaks and total kill of many adult post oak trees. This was one hot fire!

Some viewers might invoke a Smoky Bear matra and allege that death of post oaks was the result of wildfire and that fire prevention (fire suppression) would have saved these "prime-age" adult trees. No, wildfire prevention was a desired but not a reliable option. Conditions of high human activity (a border-to-border US highway ran right by this woodland or savanna) combined with Extreme fire danger rating (high winds, tenderbox-dry fuel, high temperatures, and low humidity) made this stand of Cross Timbers vegetation a wildfire waiting to happen. Instead, detrimental impacts of a sooner-or-later wildfire would have been minimized had this savanna range been routinely burnt by prescription. Periodic prescribed burning of this natural vegetation every three to six or eight years would have reduced woody undergrowth and density of green-brier in tree crowns which, in absence of fire, formed a fire staircase to tops of mature post oak trees. This heavy, ground-to-crown fuel load permitted development of an extremely intense wildfire that resulted in death of a high proportion of adult post oaks. By the way, the wildfire also "did quite a number" on the typically fire-tolerant fiddleleaf green-brier. Conditions of this high-intensity fire greatly reduced cover and density of green-brier as well as of post oaks.

In other words, the catastrophic death of these fine "in-their-natural-prime" post oaks and invasion by other plants, especially western ragweed (Ambrosia psilostachya) which became the new dominant plant species, was not due so much to a bad thing (wildfire) or too much of a good, natural thing (fire), but rather by too little of a good thing (prescribed fire). Too much (too hot, too great a heat intensity) of a bad thing (wildfire) was the result of carelessness or accident (exact ignition source apparently was never determined) and lack of prescribed burning. These two factors or situations under conditions of Extreme fire danger led to an extremely intense wildfire. This was improper fire management. Fire became a factor of mismanagement not because of fire occurrence, but because of lack of fire (prescription fire); not because of too much fire all at once, but because of too little fire over a longer span of time. In the parlance of Fire Science, fire intensity was excessive (a very hot wildfire) because frequency of fire (cooler, more frequent, prescribed fires) was inadequate. Technically, fire--frequent or infrequent, prescribed or accidental--had been non-existent until one big fire "made up the difference".

Sooner or later, wait long enough, inevitably (at least a very high probability) it will burn. The only choice in the matter is whether it burns when the manager wants it to burn and at levels of intensity, frequency, season, etc., that are consistent with sound resource management or whether it burns when results of fire are more detrimental and management of fire is more difficult.

40. After the fire was gone- A post oak- little bluestem savanna (or former savanna) in the West Cross Timbers as it appeared five warm-growing seasons after a catastrophic wildfire (March 2011) under Extreme fire danger rating conditions caused top-kill or complete kill of almost all adult post oaks. Wildfire effects combined with continued heavy grazing to at least borderline overgrazing--both pre- and post-fire-resulted in domination of this post-fire vegetation by western ragweed. There was some resprouting of post oaks (stump sprouts) and growth of fewer post oak seedlings. There were also numerous plants of skunkbush sumac (Rhus trilobata= R. aromatica) and widely scattered plants of pokeberry (Phytolacca americana). There were some heavily grazed plants of little bluestem and a few individuals of Louisiana sagewort, western mugwort, or grey sagewort (Artemisia ludoviciana).

High fuel load of fiddleleaf green-brier, especially that in tree crowns, was the factor that permitted the high-intensity wildfire to kill (either outright--total or complete--kill or top-kill) adult trees of post oak. This fire had the same net physiological impact on post oaks as a crown fire in conifers even though post oaks were dormant and not leafed out. Death of aboveground tree tissue (from trunk to crown), especially the cambium layer, resulted from the extreme heat (high intensity) of the wildfire that burned under conditions of Extreme fire danger.

Incidentally (and ironically), this high-intensity wildfire also killed most of the fiddleleaf green-brier. Five warm-growing seasons after the wildfire there had been only limited resprouting of fiddleleaf green-brier among its remaining, scorched, dead shoots. Apparently, response of fiddleleaf green-brier to fire depends on frequency and intensity of fire. As shown elsewhere in Range Types of North America (eg. sand post oak-fiddleleaf green-brier scrub forest under Miscellaneous Forests) even a hot summer wildfire merely top-killed shoots of this species and it quickly recovered (perhaps even benefitted) from the fire. Tyrl et al. (2008, p. 569) concluded that this mid to late successional stage-species is adversely affected if it is "periodically" or "frequently" burned. In the instance shown and described here, one extremely intense-low frequency fire "did in" fiddleleaf green-brier for at least a half decade.

In this savanna some trunks and larger limbs of post oak snags had fallen and many more were in process of falling. This was a very ghostly and erie vegetative landscape. This tree graveyard was downright spooky at night.

Jack County, Texas. Early October; early autumnal aspect. FRES No. 15 (Oak-Hickory Woodland Ecosystem). K-75 (Cross Timbers). SRM 732 (Cross Timbers, Texas; Little Bluestem- Post Oak). SAF 40 (Post Oak-Blackjack Oak, Cross Timbers variant). Sandstone Hills range site. Cross Timbers- Western Cross Timbers Ecoregion 29c (Griffith et al, 2004).

41. Fire aftermath in the West Cross Timbers- The recovering vegetation via secondary plant sucession in a (former) post oak-little bluestem savanna five warm-growing seasons after an extremely intense, rapidly moving wildfire (March) top-killed or completely killed adult "in-their-natural-prime" post oak trees. A history of heavy grazing (probably, overgrazing at times) and lack of periodic fire lead to an excessive cover of fiddleleaf green-brier reaching from ground level to tree crowns that provided fuel for a wildfire. Under conditions of Extreme fire danger and with the heavy fuel load an extremely hot fire, the cause of which apparently was never determined, either top-killed or completely killed almost all post oaks.

While many and, probably, most post oaks had beeen killed some had sprouted from stumps (basal trunks). There were also some post oak seedlings, but at end of five years after the fire, most existing plant cover was of western ragweed with skunkbush sumac having second greatest plant cover. There were also some plants of pokeberry (pokeweed) and Louisiana sagewort or western mugwort.

The first two of these five slides featured trunks of dead, large post oaks and in a local area where almost all living plant cover was of western ragweed. The third and fourth slide presented healthy post oak resprouts (stump sprouts) and, in the third slide, a large pokeweed to their left. Most most plant cover seen in the third and fourth slides was of western ragweed. The fifth slide were from a part of the devestated savanna that had considerable cover of skunkbush sumac (almost all cover in foreground) with cover of the overall dominant western ragweed farther back (midground), and shoots of resprouted post oaks beneath snags of top-killed adult trees (background).

By the way, the wildfire also "did a number" on fiddleleaf green-brier. Five warm-growing seasons after the wildfire, fiddleleaf green-brier was still in early stages of recovery. Fiddleleaf green-brier response to fire in general, and to this wildfire in particular, was discussed in the immediately preceding caption. As it turned out, fire exclusion and heavy grazing to overgrazing that permitted excessively (unnaturally) high density of shoots and heavy cover of green-brier (ie. a brush invasion) was about as detrimental to green-brier as it was to post oak.

42. Not by fire alone- At end of the fifth warm-growing season following a catastrophic wildfire in late winter (March) little bluestem along edges of a post oak-little bluestem savanna (former savanna "for the time being") in the West Cross Timbers was continuing to recover--where it was protected from heavy utilization (first two of these three slides) and managing to survive where it had been subjected to overuse from beef cattle (third slide). The first two slides presented a fenceline contrast with ungrazed, but available-to-wildlife and sometimes-mowed little bluestem on the right of way of US highway 281 (foreground in first slide; right foreground in second slide). The little bluestem-dominated vegetation was a consociation of little bluestem with some "incidental" plants of sand dropseed (Sporobolus cryptandrus), hairy grama (Bouteloua hirsuta), purple-flower dropseed (S. clandestinus), and western ragweed in that relative order.

The overutilized little bluestem was in the cattle-grazed, burnt-over post oak-little bluestem savanna range. These were some of the relatively few plants of little bluestem that were still alive on this range. This range had been heavily utilized (a conservatively stated description) and, certainly, periodically overgrazed (probably a more realistically stated description) over a number of decades. In fact, it was this high degree of use/overuse/overgrazing that contributed to an invasion (= an excessive cover and density) of fiddleleaf green-brier which was the main fuel that permitted the wildfire to burn with such high intensity that it either killed outright or topkilled adult post oak trees.

Yes, fiddleleaf green-brier is a native species (and, undoubtedly at some proportion, a component of the climax range vegetation). All plant species found on this range were native including western ragweed, pokeweed, skunkbush sumac, hairy grama, and sand dropseed. As any beginning student in Range Management knows, it is the relative proportion of these species in the plant community, the species composition of the range vegetation, as compared to the potential natural vegetation that determines range condition and trend. In the absence of range condition/trend it is range utilization (degree of use) that serves as the "barometer", the benchmark or baseline, for ecological status (= state, productivity, and general "health") of range vegetation.

The two fenceline contrast (exclosure/inclosure) views portrayed--rather graphically--the difference between heavy use in the cattle range versus non-grazing in the cattle-excluded highway right of way. The differences in species composition between these two treatments was equally graphic and due totally to cattle grazing (that is, to the "treatment" of cattle grazing as managed by humans). Bear in mind that both the cattle-grazed range and the non-cattle grazed highway right of way had burned at the same time (note charred fence post in the second slide) and that white-tailed deer had access vegetation on both sides of the fence.

It should also be emphasized that both of these two fenceline contrast views were taken at the outer edge or marginal contact of the post oak-little bluestem savanna. Both the grazed portion of the range and the highway right of way were out of the savanna such that the contrast showed and discussed the impact of grazing by cattle versus not grazing by cattle only of the herbaceous component (mostly of little bluestem).

The third slide showed overuse of three little bluestem plants on the range being grazed by beef cattle (foreground of the image). There was not a single sexual shoot remaining on these plants. In other words, sexual reproduction would have been impossible on any of these three genetically distinct plants (genotypes). Establishment of "new" plants (seedlings) could not have occurred. If any (or all) of these three plants died, the range would be further depleted of the potential dominant herbaceous species of the climax range vegetation. Such death due to overuse is the "seed", the "building block" of overgrazing.

The green plants (shoots) in the third slide were western ragweed, none of which had been grazed. Under this pattern of overuse/overgrazing western ragweed would soon predominate over little bluestem even though little bluestem is the potential dominant and western ragweed is an increaser and of potentially much less cover in the climax vegetation. This condition (as in range condition) was readily seen in the two fenceline contrast shots. The non-green herbage (herbaceous cover) all around the three cespitose little bluestem plants in the third slide was of hairy grama, purple-flower dropseed, and sand dropseed (in that relative order on this overused/overgrazed range). These other three, native, perennial grasses had also been grazed, but a lower proportion of their biomass and photosynthetic leaf/culm area had been removed. Hence, the competitive advantage was with these three increasers and not the decreaser, little bluestem. What students saw here was overgrazing--relative change in plant species composition of the range vegetation due to overuse--in the slow motion of still photography.

**It was overuse (leading to, at least periodic, overgazing) of the climax grass species, the dominant of which was little bluestem, combined with lack of periodic (high frequency-low intensity) fire that under conditions of Extreme fire danger permitted death (top-killing to complete or total killing) of both post oak and fiddleleaf green-brier. It was ironic that mismanagement of both grazing and fire that led to a build-up of fuel--excessive, abnormal density and cover of fiddleleaf-green-brier--resulted in a corresponding high death rate of the same plant species that served as the main fuel source. Ultimately, overuse/overgrazing, combined with absence of fire, was detrimental even to the invading brush species for which such mismanagement was largely responsible for.

43. A sage worty of fire- Crown (first slide) and part of shoot (second slide) of Louisiana sagewort or western mugwort growing on a post oak-little bluestem savanna at end of the fifth warm-growing season after an extremely intense wildfire (in March 2011) top-killed some and totally killed other adult post oak trees. High winds, high ambenient temerature, low humidtity (Extreme fire danger rating), and a heavy load tenderbox-dry fuel "fed" an extremely intense wildfire that devestated this natural range vegetation. Much of the fuel was shoots of fiddleleaf green-brier that extended from the soil to oak crowns.

Louisiana sagwort was one of the remarkably few species found growing on the sere of this savanna vegetation. Secondary plant succession "was in full swing" with the dominant species overall being western ragweed with skunibush sumac a distant second. There were also some plants of pokeweed (pokeberry) and westrn mugwort like the specimen featured here and in the next slide. Louisiana sagewort most commonly grows around edges of oak-dominated communities.

A very good treatment of Louisiana wormwood or sagewort was Tyrl et al. (2008, ps. 264-265). Louisiana sagewort is sometimes found as individual plants (as seen here), but more commonly the rhizomatous forb grows in small colonies. Perhaps the wildfire had killed shoots or, even entire plants of western sagewort in this savanna and only a few individuals had rocovered or arisen from seed in this fifth year following the wildfire.

Jack County, Texas. Early October; peak standing crop.

44. Upper shoots- Stems and branches of the upper shoots of Louisiana mugwort or western sagewort growing in the recovering range vegetation of a post oak-litttle bluestem savanna five warm-growing seasons following a late winter (March), ast-moving, extremely hot wildfire that killed (either outright and totally killed or top-killed) adult post oaks at the peak of their life cycle. This individual of the late successional stage Louisiana sagewort had either survived or was a younger plant that arose following the wildfire that "devestated" the then-existing vegetation.

This Artemisia species has generally ben regarded as Tyrl et al. (2008, p. 265) explained that this was one of the single most medicinally important plant species for the American Indians. Mentholatumh

Jack County, Texas. Early October; peak standing crop.

45. Sand prairie- An ecotonal tallgrass prairie dominated by little bluestem with yellow Indiangrass and sideoats grama as associate species that developed on deep sand in the West Cross Timbers. This grassland was contiguous with a dwarf forest or shrubland, known locally as sandrough", comprised of sand post oak (Quercus margarettiae) and fiddleleaf greenbrier (Smilx bona-nox). At landscape scale this prairie could be seen as a patch of grassland situated among a matrix of "sandrough".

The conspicuous yellow composite was stiff-leaf goldaster (Heterotheca stenophylla).

Although the soil of this grassland was primarily deep sand it had enough clay and differed (largely in depth and proportion of sand) from the adjoining Patillo-Nimrod-Arenosa soil complex that supported scrub oak trees or large shrubs.

This climax range plant community could fit into either tallgrass prairie (Grand Prairie) or Cross Timbers vegetation so it was included in both chapters, Tallgrass Prairie and Tallgrass Savanna.

Eastland County, Texas. Mid-October; peak standing crop, full-bloom stage to fruit-ripe stage in most plant species.

46. Chewed up by ice- Young blackjack oak (first or upper slide) and ancient post oak (second or lower slide) in Sandstone Hills Cross Timbers with extreme ice damage from a late autumn winter storm that brought rain, freezing rain, sleet, and snow which built up to such accumulations (depths of one to four inches) of ice on trees that limbs, large to small branches, and twigs were broken. Some trees like this old post oak (and the ancient post oak presented immediately below) were completely topped with their crowns more broken than Jack when he fell down. Some trees were even toppled by uprooting from heavy ice accumulations.

When rangemen and foresters speak of agents of defoliation the consideration is not limited to grazing/browsing animals. "Fire and ice" along with wind, frost, drought and others keep the Cross Timbers far from being a Garden of Eden, at least from a tree's vantage point. Incidentially, all this ice-downed wood is fuel just waiting for a fire that could be readily ignited by spring thunderstorms that undoubtedly await these survivors. And you thought you had it rough!

Lincoln County, Oklahoma. Mid-December.

47. "Gittin' old ain't for sissies"- This grand ole patriarch was not favored to live all its "golden years" as "happy times". This ancient specimen was hit by a severe or extreme ice storm a week before these two photographs recorded the tragic event in its long life. A late autumn (9 December, 2007) ice storm (a winter mix of rain, freezing rain, sleet, and snow) struck the Cross Timbers in the Sandstone Hills or northern Oklahoma with the devestation of a twister. This ice storm was due to the phenomenon of overriding, the atmospheric condition that results from the meeting (a collusion) when warm, moist air from the Gulf of Mexico and a cold Arctic air mass (a Norther). The accumulation of ice (up to several inches thick) wrought damage to trees varying from loss of small branches to major limbs to, as in this case, the complete topping of a large tree.

And this might not be the end of the tragedy. The heavy accumulation of downed timber is fuel-loading just waiting for a fire that could be sparked readily from spring thunderstorms ( which in Oklahoma are more numerous and every bit as notarious as ice storms). This senior citizen of the Cross Timbers does not seem destined to meet a mild end to its old life, but stay tuned as we follow its saga.

Lincoln County, Oklahoma. Mid-December.

48. Post oak- Young leaves and catkins of the dominant tree species of the Post Oak Savanna and Cross Timbers of Texas and most of the Cross Timbers Oklahoma into Kansas except on sites dominated by

49. Leaves and fruit of post oak (Quercus stellata)- Characteristic apex of short shoot of post oak showing typical arrangement of an extra heavy crop of acorns. Post oak is a member of the Quercus subgenus Leucobalanus, the white oaks, whose leaf veins do not extend as spines, bristles, or "teeth" beyond leaf margins. Leucobalanus species bear fruit annually (ie. acorns mature in the same growing season) so that acorns are borne on current-season shoots (leaders). The kernal or "meat" of acorns in the white oak subgenus are sweet-tasting (versus the bitter kernals of red or black oaks). Erath County, Texas. October.

50. Post oak acorns- Detail of cup and nut of post oak acorns. Erath County, Texas. September.

51. Off to a growing start- Seedling of post oak at start of its second year (warm-growing season) of life on a Sandy range site in the West Cross Timbers of northcentral Texas. This baby plant was growing in association with Indiangrass. little bluestem, and Muhlenberg's caric sedge, bracted sand sedge, or sand sedge (Carex muhlenbergii). Outer husks of the acorn from which this seedling emerged were visible in both photographs.

Hunewell Ranch Ranch, Tarleton State University, Erath county, Texas. Mid-April; leaf-whorl seedling stage of phenology.

Short on shoots- Example of short shoots on post oak in the West cross Timbers. Short shoots lack a well-defined terminal bud and have shorter internodes in contrast to long shoots with a pronpunced, well-developed terminal bud and elongated internodes. Students should read Sosebee (1977, ps. 272-278).

Hunewell Ranch, Erath County, Texas. Late October.

52. Blackjack oak- Young leaves and catkins of the second major tree species of the Cross Timbers. In the more northern parts of the Cross Timbers like the Osage Questas and Chautauqua Hills in northern Oklahoma and southern Kansas blackjack nudges out post oak to become the climax dominant tree. The ecological range of the parasitic Christmas mistletoe which preys only on the red oak group (Erythrobalanus subgenus of Quercus) does not extend this far north. Both oak slides taken in Ottawa County, Oklahoma, April.

53. Normal appearance of leaves and acorn on a leader of blackjack oak- Blackjack is a member of Quercus subgenus Erythrobalanus (red or black oaks) one characteristic of which is extensions of veins or ribs of leaves beyon the margin so as to appear as spines, bristles, opr "teeth". Acorns of Erythrobalanus oaks require two growing seasons for development and maturation. Thus these fruits are borne on twigs (leaders) that were produced during the previous growing season. Meat of the acorn is bitter or tart-tasting. Erath County, Texas. October.

54. Blackjack (Quercus marilandica) branch-Lateral shoot of blackjack oak with leaves and fully mature fruit. Erath County, Texas. October.

55. Leaves and acorn (at full maturity) of blackjack oak- Detail of ripe acorn and two leaves of blackjack oak. Erath County, Texas. October.

56. Three sample trunks- Trunks of three small (though not young) trees of blackjack oak. Trunk in first (uppermost) slide was of a tree growing at the edge of an oak-hickory savanna that was approximately two decades older than the two fifty-five-year-old trunks in the second and third slides. Bark on the younger--and (for whatever reasons) runt or scrub trees--was more typical of blackjack oak than the comparatively less knobby bark of the older tree. There is considerable variation in bark of blackjack oak.

Ottawa County, Oklahoma. Early January.

57. Co-dominants and (typically) the associate- Blackjack oak, Texas or black hickory, and post oak left to right, respectively. Post oak and blackjack oak are the overall co-dominants and black hickory the associate species in the oak-hickory-tallgrass savannahs of the Ozark Plateau and Osage Plains/Cherokee Prairie portions of the Central Lowlands physiographic provinces to the Eastern Cross Timbers of the Central Lowlands-Great Plains ecotone (the Prairie-Plains Border).

This "line-up" of the major tree species in the eastern deciduous forest-tallgrass prairie transition zone (ecotone) was from the western edge of the Springfield Plateau section of the Ozark Plateau province. Tawdy cover in background was poverty oatgrass (Danthonia spicata).

Ottawa County, Oklahoma. Late July.

58. Line-up of the three principal players- Two "line-up" views of seedlings of post oak, blackjack oak, and black hickory growing in shallow, rocky soil on a south slope in the western Springfield Plateau. In the first slide larger seedlings of post oak (left) and larger seedlings of post oak (right) flanked smaller seedlings of black hickory (center). In the second slide, leaves on the trunk of blackjack oak at right, seedlings of post oak in center, and seedlings of black hickory (right margin) represented this three tree species in an area where oak-hickory-tallgrass savannas and the westermnost oak-hickory forest association form a vegetational mosaic with tallgrass prairie.

Post oak, blackjack oak, and black hickory are the three most important tree species in far-flung oak-hickory communities extending from the westernmost oak-hickory forest association of the eastern deciduous forest through the oak-hickory-tallgrass savannahs of the Ozark Plateau to the Eastern Cross Timbers of the western part of the Central Lowlands province. Overall, across this inter-provincial region, post oak and backjack oak are co-dominant tree species while black hickory is the associate. There are some areas where any one of these three species is dominant with any one of the three being the associate and even areas where they are tri-dominants.

Species ranges of these three species extends far to the east of the climax range vegetation that was considered in this chapter.

There was quite a bit of poverty oakgrass growing beside these three hardwood species and in the brown grassy patch behind them.

Ottawa County, Oklahoma. Late July.

59. Babies of the co-dominants- Seedlings of post oak and blackjack oak at far-western perimeter of the Ozark Plateau physiographic province (western edge of the Springfield Plateau of the Ozark Highlands). In the first of these two slides leaves of blackjack oak seedlings were in the uppr left corner while all other leaves were of post oak seedlings. In the second slide most of the leaves were on blackjack oak seedlings while leaves of post oak seedlings were in the lower left corner.

All these leaves were of "normal-size" (ie. not unusually large shade leaves). Seedlings were growing on a south slope of thin, rocky soil typical of the Ozark Plateau physiographic province. These views were at the western margin of the Ozark Highlands, the Springfield Plateau, approaching the eastern edge of the Cherokee Prairie or Osage Plains of the Central Lowlands physiographic province.

Some shoots of poverty oatgrass were present in the center of the first slide.

Ottawa County, Oklahoma. Late July.

60. Closer view of baby co-dominants- Seedlings of blackjack oak at left and post oak at right (first or upper slide); seedlings of blackjack oak with their large shade leaves surrounding--to left and right of--seedlings of post oak with regular-sized or non-shade leaf dimensions (second or lower slide). These photographs were taken in the western margin of the Springfield Plateau section of the Ozark Plateau physiographic province.

Post oak and blackjack oak are co-dominant tree species across a vast region extending from the oak-hickory forest association (the driest, farthest west, and most marginal part of of the eastern deciduous forest) of the Ozark Plateau through the oak-hickory-tallgrass savanna of the Central Lowlands to the Eastern Cross Timbers nearing the eastern edge of the Great Plains. These do-cominants are often associated with black hickory which is usually the associate tree species.

These tree species have biological (species) ranges far to the east of the savannahs, forests, and grasslands under consideration here. That aspect was not treated here.

Ottawa County, Oklahoma. Late July.

61. Co-kings of Cross Timbers- A single tree of blackjack oak (left and rear) and of post oak (right and foremost) represented the co-dominant tree species of various climax range plant communities extending from the oak-hickory forest association (the most marginal, farthest west forest form of the eastern deciduous forest) in the Ozark (Springfield) Plateau through oak-hickory-tallgrass savannas of the Central Lowlands (especially the Osage Plains/Cherokee Prairie portions) to the Eastern cross Timbers that developed near the eastern margin of the Great Plains. (The species ranges of these hardwoods extends far to the east of range vegetation considered in this chapter.)

Individual plants of these two species range in size and shape from stately trees approaching relatively immense dimensions down to shrub habit with scrubby trees somewhere in between. Interestingly enough, this array of size and morphological features is to be found throughout the biological ranges of these species and in specimens growing in forest, savanna, and even grassland vegetation. Genotypic and phenotypic plasticity is a key feature in adaptation of these wide-ranging range plants. Two admirable arboreal species.

Ottawa County, Oklahoma. Late July.

62. Co-kings side-by-side- Trunks just below start of crowns in blackjack oak (left) and post oak (right) at union of a tallgrass prairie and black oak (Quercus velutina) forest in the Springfield Plateau. These two oak species are the overall co-dominants in the western portion of the oak-hickory association of the eastern deciduous forest westward to the oak-hickory-tallgrass savannahs of the Ozark Plateau through the Osage Plains/Cherokee Prairie of the Central Lowlands, and finally, to the Eastern Cross Timbers at eastern boundary of the Great Plains.

On more moderate (more mesic, less rocky, slightly deeper soil) habitats post oak is typically more abundant (eg. greater cover, higher density) than blackjack oak which rates the abundance advantage on habitats that are more marginal for survival and production of these oaks. Blackjack oak frequently becomes number one to the then-number two post oak in habitats with stonier, thinner soils such as those in the Eastern Cross Timbers of central Oklahoma.

Ottawa County, Oklahoma. Late July.

63. Black co-king- Trunk of blackjack oak downward from base of crown (upper or firest slide) and leaves on living branch along with pins (dead limbs) of this same tree (lower or second slide) growing in the western part of the Springfield Plateau. Blackjack oak is typically a somewhat less abundant co-dominant (with post oak) in the western portion of the oak-hickory association of the eastern deciduous forest westward to the oak-hickory-tallgrass savannahs of the Ozark Plateau through the Osage Plains/Cherokee Prairie of the Central Lowlands, and finally, to the Eastern Cross Timbers at eastern boundary of the Great Plains. Blackjack oak is frequently dominant on more harsh environments.

Ottawa County, Oklahoma. Late July.

64. Savanna specimen- An old-growth black oak (Quercus velutina) on a one-time tallgrass prairie savanna. This old-age, (and now senescing) tree established and grew on a big bluestem-dominated prairie and matured into the "shade tree" (that is, open growth) form characterized by a fully developed crown. Black oak is primarily a forest tree species--and a major species in the forests and savannahs of the ancient Ozark Mountains--but black oak is also one of the major oak species, after the co-dominant post oak and blackjack oak, on the oak-hickory-tallgrass savannas and woodlands.

The old codger was the last remnant, about the last plant, of a former oak-hickory savanna that through overgrazing, overmowing, overseeding, haying, etc. was converted to a "trash pasture" with "a little of everything" besides the native grasses and palatable forbs. This specimen served as an example for both 1) its species at maturity and 2) a savanna form of its species.

Springfield Plateau portion of the Ozark Mountains, Ottawa County, Oklahoma. Late July.

65. Morphology of the lower end on a savanna specimen- Trunk and lower crown of the old-growth black oak introduced in the immediately preceding two-slide/caption set. This magnificant specimen grew on an Ozark (Springfield) Plateau savanna on which almost all other native plant species had been obliterated by overgrazing and related stock-farming activities. Relict stands of big bluestem along with such forbs as catclaw sensitive-briar (Schrankia uncinata) and Illinois bundleflower (Desmanthus illinoensis) remained growing in fencerows all around this tree which, in the spirit of James Fenimore Cooper, remained "The Last of the Mohigans" of the pre-white man savanna.

Sad, but this old-growth relict grew along the author's route to the one-room schoolhouse of his first eight school years and, up to this time, it still stood to greet him on adult walks to the yellow-brick schoolhouse which was in worse shape than this slowly senescing black oak.

Springfield Plateau portion of the Ozark Mountains, Ottawa County, Oklahoma. Late July.

A forester's or rangeman's Sherlock Homes observation: keen observers of the above four photographs will have noticed that there were no lower branches or leaves of the above old-growth black oak. This was the direct result of browsing by beef cattle (usually cows and calves, rarely stockers). This photographer observed cattle reaching up their necks and extending their tongues as far as possible to grasp leaves and small twigs which were readily eaten. A popular myth is that because cattle are, by general preference, grazers rather than browsers (scientific fact) cattle do not eat browse (leaves, buds, twigs, etc.) of trees (absolute balderdash). This conclusion is wrong and based on lack of observation-- both of 1) cattle feeding behavior and of 2) physical evidence of plant material removal by cattle.

Yes, white-tailed deer also ranged over this area and, most likely, deer did eat some foliage from this black oak, but the stocking rate of cattle in this small, fenced enclosure was much greater than that of free-ranging white-tailed deer. Furthermore, white-tailed deer were absent from this pasture (this entire general area in fact) for a period of at least a half century.

The absence of leaves and small twigs from the black oak down to heights at which cattle could reach constituted a broswe line, "a well-defined height to which browse has been removed by animals" (Kothmann, 1974). Development of a browse line is commonly known as highlining. Presence of a browse line indicates either 1) overbrowsing or, in cases where such tree material is very limited, 2) consumption of feed produced by ice cream species. Ice cream species are those plants that are so palatable they cannot be maintained under proper stocking rates. There is no evidence to indicate that black oak is an ice cream species to cattle.

It is axomatic that if cattle find black oak leaves and buds palatable enough that they will put forth extra grazing (browsing) effort to reach high to get this feed, cattle will certainly eat black oak seedlings that are at the grazing level of grass where less expenditure of energy and grazing motion is needed. Lack of recruitment of black oak on this former savanna was due, at least in large part, to consumption of black oak seedlings by cattle. Forget about "brush goats". Grass-preferring cattle are more than adequate to prevent regeneration of black oak on this climax savanna of which black oak was a major woody species (apparently the dominant tree species). Foresters know what they are talking about when they state that heavy grazing by livestock (including cattle) will retard regeneration of hardwood species. Oak reproduction (regeneration of any natural hardwood species) must be a consideration in maintenance of natural hardwood-tallgrass savannahs the same as invasion by brush (any woody species--including native hardwoods, such as black oak--having excessive density and cover). This is wise use management of range and forest resources.

Cattle and deer (as well as fox squirrels [Sciurus niger] and other vertebrates, including birds) readily ate acorns produced by this black oak. Such consumption of acorns (the sexual propagules) was obviously a limiting factor in local regeneration of black oak. Conversely, free-ranging wildlife were also agents of dispersal as, for example, when squirrels or woodpecker species removed, transported, and stored acorns at considerable distance from the parent tree. Squirrels buried acorns and, hence, planted trees at relatively long distances from the parent black oak. This was most likely the explantion for establishment of a black oak seedling, offspring of this old-growth black oak, at three or four times the length of tree height away from the seed source (see below).

66. Leaves and acorns- Characteristic leaves and immature acorns of black oak on the old-growth specimen shown and described above. This tree was in the far western edge of the Ozark (Springfield) Plateau.

Ottawa County, Oklahoma. Late July.

Oraganization note: more photographs and description of leaves and acorns produced on this tree were included in the Black Oak section in Oak-Hickory Forests-I in Range Types of North America.

67. The proof of any fruit; the only measure of survival- "A chip off of the old block". "That acorn didn't fall far from the tree". Both of these old (and, perhaps, hackneyed) expressions aptly expressed the fact that this large (about a yard tall) seedling of black oak was the sexual progeny of the immense old-growth specimen presented and explained above. This seedling was roughly three to four times the height of the adult old-growth black oak away from its parent. It was growing safely in a fencerow where cattle and, so far, a rotary shredder had not eaten or broken it off. This seedling most likely grew from an acorn planted by a fox squirrel.

There were no offspring trees (that means zero)--of any age or size--from the old-growth black oak anywhere (at any location) that cattle grazing/browsing or mechanical mowing/shredding had occurred at any time over roughly the last century.

It was shown and explained above that beef cattle (and dairy cattle in decades before that) had highlined (removed all tree material within their reach, that is to this height).

The "proof of the pudding' for any plant propagule is that it produce more plants (or plant parts). One acorn had "done its thing" in this case shown here. The final, the only, measure of any species is that it reproduce (regenerate, recreate) its kind. The only measure of the "genetic fitness" of the individual genotype is that it leave progeny to replace it. This old-growth, parent black oak as a representative of its species had done this (ie. it "measured up").

In the instance presented here, failure (of genotype or species) in regard to reproduction, to regeneration, would not have been a failure to natural phenomenon (not failure of natural selection), but rather failure in an unnatural set of conditions created by contemporary man (failure to have fitness to a manmade habitat, to an environment in which man was an artificial and not a natural part).

In final analysis, not only had the native herbaceous species been lost from this savanna, but the woody component was being lost-- only at a slower rate--such that in only a few years none of the savanna will remain. Specifically, the savanna will remain only in fencerows--and only that until hatchet-happy, make-work county road workers destroy it.

Springfield Plateau portion of the Ozark Mountains, Ottawa County, Oklahoma. Late July.

68. Texas ash tree (Fraxinus texensis= F. americana subsp. texensis) in spring uniform- This ash was the one featured above in photographs that showed a composite of the Western Cross Timbers old-growth community. This tree was in the immediate pre-bloom phenological stage and with the bright, glossy, young leaves that are characteristic of deciduous species in the Cross Timbers during spring before months of hot Texas sun turns them a dark forest green.

Parker County, Texas.

69. Shrub form of Texas ash- Multiple-boles (shoots or trunks) and relatively small stature of this Texas ash qualified it as a example of the shrub form of this species. This and the preceding photograph provided instructive examples of the distinction-- and often an arbitrary one-- between tree and shrub, a beginning lesson for students in the Principles & Practices of Range Management course. Learn the lesson.

Lake Mineral Wells State Park. Parker County, Texas. March (vernal aspect).

70. Leaders of Texas ash- Shoot tips of this Cross Timbers shrub sport new spring foliage and inflorescences. Palo Pinto County, Texas. March.

71. Inflorescences of Texas ash- Detail of flower clusters of this associate species of the Cross Timbers. Palo Pinto County, Texas. March.

72. Glossy new leaves of cedar elm (Ulmus crassifolia)- A branch and spring leaves of this Cross Timbers associate species had the shinny, waxy coat of newly expanded foliage that is characteristic of Texas trees and shrubs before the brutal heat of a long, baking summer takes it's toll.

Lake Mineral Wells State Park. Parker County, Texas. March.

73. Dogwood of the Cross Timbers- Roughleaf or Drummond's dogwood (Cornus drummondii) is a widely distributed "kissin' cousin" of the better-known flowering dogwood (C. florida). Roughleaf dogwood has much smaller flowers and is better adapted to harsher habitats than its more mesic and florally endowed "cousin". For example, roughleaf dogwood is native to roughly the eastern half of the Lone Star Star so as to grow far west of flowering dogwood. Roughleaf dogwood is the Cornus species that is common in the Cross Timbers and Prairies vegetational area of Texas as well as northward through central Oklahoma and as far north as South Dakota. This is also the most widely distributed dogwood throughout the both the tallgrass and mixed prairies of the Central Lowlands physiographic province (McGregor et al., 1977, ps. 204-205).

Roughleaf dogwood was introduced as an important and common shrub on moister environments of the central grasslands of North America, understorey woody plant in Cross Timbers and local bottomland forest communities, and member of savannahs and general ecotones among grassland and forest range types. Roughleaf dogwood is also an major species in local postclimax communities within more general and larger range plant communities (macro-communities) as for example sandrough scrub in the West Cross Timbers.

The pretty specimen shown here was adding beauty to the understorey of a stand of post oak-dominated West Cross Timbers. Vines (1960, p. 798), Stephens (1973, ps. 416-417), Kurtz (1997, ps. 86-87), and Tyrl et al. (2003, ps. 512-513) were good, general treatments of roughleaf dogwood.

Erath County, Texas. Late May. Full-bloom phenological stage.

74. A pack of rusty flowers- Flower cluster of rusty blackhaw (Virburnum rufidulum). These examples were from a sandrough range type, a deep sand habitat existing as postclimax (monoclimax theory) or edaphic climax (polyclimax theory) with the greater West Cross Timbers.

Erath County, Texas. April.

75. Doggone it, Crosss Timbers- Crown of a large specimen of roughleaf dogwood (Cornus drummondii) growing along the bank of a small stream (Richardson's Creek) in the West Cross Timbers-Grand Prairie mosic of northcentral Texas. The canopy of this big plant was loaded with hundreds of drupes, the fruit type of Cornus species. Details of drupes and leaves on this particular specimen were presented in the next two slide-caption sets.

Tarleton State University Hunewell Ranch, Erath County, Texas. Late October; fruit-ripe stage.

76. Doggone study- Bunch or cluster of drupes and leaves of roughleaf or Drummond's dogwood. These two examples had been produced on the large, spread-crowned specimen introduced in the immediately preceding photograph. This individual was growing on Richardson's Creek, a small stream running through a landscape patchwork of Grand Prairie and West Cross Timbers in northcentral Texas.

The fruit type of dogwood (Cornus) species is a drupe, "a fleshy fruit with a firm endocarp that permanently encloses the usually solitary seed, or with a portion of the endocarp separately encloseing each of two or more seeds" (Gleason and Cronquist, 1991, p. 872). In the specific instance of Cornus species the drupe has one stone which has one to five locules each of which has a single ovule developing into a seed (Gleason and Cronquist, 1991, p.323).

Tarleton State University Hunewell Ranch, Erath County, Texas. Late October; fruit-ripe stage.

77. Drupped in the Cross Timbers- Ripe and over-ripe (dried) drupes of roughleaf or Drummond's dogwood on a large plant growing on the bank of a small stream (Richardson's Creek) in northcentral Texas in a landscape mosaic of Grand Prairie and West Cross Timbers. Drupes of roughleaf dogwood are borne in groups or clusters that are typically widely spaced on red-pigmented branchlets or pedicels.

Roughleaf dogwood is a characteristic shrub of tallgrass prairie and adjacent savannahs like those of the Cross Timbers and Prairie Peninsula.

Tarleton State University Hunewell Ranch, Erath County, Texas. Late October; fruit-ripe stage.

78. Doggone fruit- Immature (first or top slide) and mature fruit (second or lower slide) of roughleaf dogwood. The former was in the Texas Blackland (also Waxyland) Prairie (Fannin County, Texas; July). Example of mature fruit was in West Cross Timbers (Erath County, Texas; October). The fruit type of dogwood is a drupe.

79. Buckthorn or Carolina buckthorn (Rhamnus caroliniana= Frangula caroliniana)- Ths shrub is a distinctive understorey species of the Cross Timbers. Cross Timbers vegetation is, of course, the western-most extension of the oak-hickory forest. It was assigned to the Oak-Hickory Forest Region as a forest-prairie trnaistion by Braun (1950, p. 177). Carolina buckthorn appears to have an ecological niche and role in the Crosss Timbers similar to that of redbud and flowering dogwood in the main body of the oak-hickory forest types. Braun (1950, p. 153) listed R. caroliniana as being associated with redbud, dogwood, common persimmon, southern buckthorn (Bumelia lycioides), and skunkbush sumac on more xeric sites in the Western Mesophytic Forest Region. In his classic description of the Western Cross Timbers (Dyksterhuis (1948, Table 2, p. 341 and Table 3, p. 342) listed skunkbush sumac and false or wooly buckthorn, chittamwood or chittam, gum bumelia, gum elastic (Bumelia lanuginosa), but strangely did not list or even make passing reference to Carolina buckthorn.

Tarleton State University Hunewell Ranch, Erath County, Texas. November, early fruit-rip stage.

80. Leader with leaves and fruit of Carolina buckthorn- The drupes of this species turn a bluish black at maturity. The fruitsin these examples were in the pinkish-red, pre-mature stage (and that is sometimes as far as they progress before birds, squirrels, and other wildlife species facilitate a pre-mature harvest.

Leaves of this species like many of the others of the Rhamnaceae (as well as Magnoliaceae) can be described as broad sclerophyll.

Tarleton State University Hunewell Ranch, Erath County, Texas. Novermber, beginning of fruit-ripe phenological stage.

81. Rattanvine or Alabama supplejack (Berchemia scandens)- This liana (woody vine) is another member of the Rhamnaceae that is common in the Cross Timbers (and eastward into the Pineywoods portion of the eastern deciduous forest types). Supplejack grows in assocaition with other woody vines, especially various grapes (Vitis species) and greenbriar or catbriar (Smilax species). The specimen of rattanvine presented here was growing on an upper terrace of a pecan bottomland forest in a transition between Grand Prairie and Western Cross Timbers. (An example of Smilax bon-nox growing alongside this supplejack plant was presented below with another Smilax species.)

Erath County, Texas. April.

82. Shoot of Alabama supplejack- Details of basal (first photograph) and upper (second photograph) parts of a shoot, the trunk, of rattanvine showing a newly emerged branch (secondary shoot) in the second photograph. Erath County, Texas. April.

83. General view of portion of rattanvine or Alabama supplejack- A section of the shoot of this wood vine species showed new leaves and an unopened flower cluster on this winter-deciduous, perennial member of the buckthorn family. Supplejack is a widely distributed (and frrequently a major) species that grows upward through several layers of this savanna to woodland range type as well as in the Pineywoods.

Erath County, Texas. April.

84. Foliage and floral organs of Alabama supplejack- Two closer-in views of leaves and flower cluster in the specimen of rattanvine or supplejack introduced above. General leaf morphology as well as specific floral features in this species are remarkably similar to those of Carolina buckthorn, the plant species shown and discussed immediately prior to rattanvine (compare to above).

Erath County,Texas.April, pre- to early bloom stage.

There are several species of wild plum (Prunus spp.) native to the prairies and savannas of central North America. One of the largest assemblies of these species in the Cross Timbers. The West Cross Timbers of Texas afforded a good example of range vegetation from which several Prunus species could be shown as examples. These examples range from those typically occurring as individual plants of small trees up to those of small to mid-size shrubs that form extensive clonal colonies known as plum thickets.

85. Thicket, hog, or creek plum (Prunus rivularis)- as indicated by one of it's common names this clonal shrub forms thickets (sometimes rather extensive ones) in the understorey of Cross Timbers (see photographs above). These expansive woody colonies provide both cover and feed for numerous species of wildlife. They are frequently a favored haunt for coveys of bobwhite quail as avid hunters of this marvelous upland game species attest. Hog plum (along with several other Prunus species of the Cross Timbers and Prairies area) also furnishes food for biped interlopers, especially in the form of delicious jam to complement homemade biscuits.

Lake Mineral Wells State Park. Parker County, Texas. March.

86. Young leaves and infloresences of thicket or hog plum- This Prunus species puts out it's new leaves and infloresecences simultaneously. There are few fragrances among native plants that are as potent yet pleasingly aromatic as those in the Prunus flower. This genus includes some of the native shrubs most favored by bona fide backwoodsmen. Prunus also includes some of the more important horticultural crops (to which prune-pickers readily accede).

Lake Mineral Wells State Park. Parker County, Texas. March.

Let's try that one again- Another set of slides of hog or creek plum growing along a small stream in a mosaic of vegetation in part of the Grand Prairie-Western Cross Timbers area. During "wet weather" the plant that these organs were growing on (as well as neighboring plants) were "standing in water".

The preceding two sets of images of hog plum had newly emerged leaves along with flowers whereas in the present three images only flowers were present. These images were taken in brighter light and were clearer and easier to see.

Richardson's Creek, Hunewell Ranch, Erath County, Texas. full-bloom phenological stage (and no doubt about that).

87. Thicket in the Cross Timbers- A large thicket of Chickasaw plum (P. angustifolia) in the West Cross Timbers. This was largely a clonal colony that developed on the floodplain of Alarm Creek. It covered roughly four and a half to five acres on the rich alluvium of this intermittant stream. In the field it is impossible to tell which individual shoots of this plant are offshoots (modules= ramets, clonal units) of older (parental or "mother") shoots because rarely new genetic plants (genets) arise from seed during those occasional years when mature fruits (drupes) are produced. The close resemblance of shoots arising from seed and those from rootstocks was shown below for P. mexicana. Rootstocks (woody rhizomes) of plants in this thicket of Chickaswa plum were also presented below.

Erath County, Texas. Late March; peak bloom.

88. Brightness of early spring- An individual shoot of Chickasaw plum growing at outer edge of the thicket introduced in the preceding photographs. This particular shoot was an asexual offshoot (clonal unit; strictly speaking, a limb from rootstocks) coming off of a rhizome that eminated from older offshoots. There were at lest four other such modular shoots behind the foremost shoot.

Floodplain of Alarm Creek, Erath County, Texas. Late March; peak bloom.

89. Blooms up close-Details of flower clusters and individual floral units on sexual leaders of Chickasaw plum. Like most Prunus species, Chickasaw plum typically blooms before it leafs out. An exception to this general pattern was the example of both newly open leaves and inflorescences on the same shoot that was used as the first of these three photographs.

Floodplain of Alarm Creek, Erath County, Texas. Early April; peak bloom.

90. Young bucks and maidens- Leader of Chickasaw plum with "green" (=immature or unripe) plums (first slide) and closer in view of some of those young plums and leaves (second slide). Can you find the part of the first slide from which the closer-in view of the second slide was taken?

These plants and their organs were growing on a deep sandy loam soil in the Western Cross Timbers of northcentral Texas. The young leaves had their "new" bright-green color before the heat and dryness of summer had taken their toll on these organs. Sort of reminded this old professor of the condition of young, luxurant, pre-cellulosic skin on college students (especially "prime" young coeds). The ole prof sees these once-green, shiny new-leafed but now past-ripe plums after the toll of decade or so and is amazed at the change in leaf and fruit epidermis. Lot more furrows in the bark, too. Enjoy the fresh spring foliage while it last. Summer break and fall semester will extract their toll. Winter follows (even in Texas).

Anyway, this was appearance of early spring foliage and still-green fruit of Chickasaw plum. Fruit type is a drupe or "stone fruit".

Erath County, Texas Early April, pre-ripe fruit stage of phenology.

91. Surer form of reproduction- Offshoots and rootstocks (woody rhizomes) of Chickasaw plum. P. angustifolia is a highly clonal (modular) species that can form extensive colonies made of such ramets or daughter shoots. An example of one such plum thicket was shown above to introduce this Prunus species. Almost all of the shoots in this thicket of over four acres were asexual shoots. An example of seedlings and asexual shoots and their close similarity was illustrated with the next Prunus species.

Floodplain of Alarm Creek, Erath County, Texas. Late March; peak bloom.

92. Native plum tree- Basal trunk (first slide) and beginning of crown or point of limb attachment (second slide) of Mexican plum (Prunus mexicana) in West Cross Timbers. Most of the native Prunus species in the interior of North American are shrubs. In fact, most of these are clonal, often forming extensive thickets (above). Mexican plum is one of the few Prunus species of the prairies and savannas of the Central Lowlands province that actually grows into a small tree.This specimen served as an good example of the arboreous (of a tree; true tree with obvious single trunk) form.

Erath County, Texas. Late March; peak bloom.

93. Spring view- Inflorescences on leaders of Mexican plum contrasted against a rare azure-blue spring sky in northcentral Texas. Erath County, Texas. Late March; peak bloom.

94. Blooms of this second plum species up close- Clusters of flowers of Mexican plum. This Prunus species almost always leafs out after blooming. Erath County, Texas. Late March; peak bloom.

95. Gittin' ripe-. Ripening plums and insect-damaged leaves of Mexican plum in the understorey of an old-growth stand of West Cross Timbers savanna. Ripe fruit falls off of shoots (unless over-eager eaters pick them off before they hit the ground). Leaves of wild-growing Prunus species almost always show this degree (or more) of insect-feeding by late growing season.

Erath County, Texas. Mid-September; nearly ripe-fruit stage.

96. Plums and prunes- Six ripe plums (first slide) showing typical fruit of P. mexicana and a ripe plum halved below an overripe, dried-out plum (second slide). Fruit type of Prunus species is a drupe, a fleshy indehiscent (not self-opening) fruit that has one seed inside a hard endocarp known as a "stone" or "pit" with this endocarp-seed unit comprising a pyrene (Smith, 1977, ps. 69, 295). The pyrene (non-botanist-types call the seed and endocarp combined a "pit" or "stone") was visible in fresh and dried plum in the right half of each.

Prune is the term for dried plum (upper plum in second slide). Hillbillies gather ripe wild plums for fresh fruit as well as fine jams and jellies. When Okies and Arkies migrate to California to harvest fruit they become "prune-pickers" (aka CIOs, California Improved Okies).

The exocarp of a drupe is the "skin" whereas the mesocarp is the "flesh". The mesocarp of Prunus drupes characteristically turns powderly as the fruit decomposes following maturity (as shown in second slide).

Erath County, Texas. Mid-September; nearly ripe-fruit stage.

97. Just up- Two seedlings of Mexican plum that only recently emerged from drupes that fell from the parent tree whose trunk was less than a yard distant (first slide) followed by detail of a slightly older (moreadvnced) seedling from the same tree (second slide).

Erath County, Texas. Late March; seedling, emergence stage.

98. Plum trees to be (maybe)- Three young seedlings of Mexican plum produced from drupes produced from the mother tree immediately above. These seedlings were obviously more advanced than the two newly emerged seedlings shown in the immediately preceding slide. All five of these sedlings were from fruit produced by the same parent tree. The rooting places of these five seedlings was just a few feet below the branches from which they had ripened and fallen. With this close proximity of offspring to parent Prunus species typically form thickets of the same species--or, sometimes even more commonly, of the same plant. Go the next slide ...

Erath County, Texas. Late March; early seedling, multi-leaf stage.

99. Seedling and sucker- A seedling, one sexual offspring, (left) and a sprout or offshoot from root, one asexual offspring, (right) of Mexican plum in the West Cross Timbers in northcentral Texas. These two progeny are from the same tree that was shown above to introduce this species. The five seedlings shown and described immediately aobve were also from this same small tree. In photographs shown here and above there were a total of six seedlings--six distinct genotypes; six unique trees--and one asexual shoot that was the same genotype as the parent tree (ie. another shoot--a limb--of the same genetic individual). Several other seedlings and root sprouts were also present that were not shown. It is in this manner that Prunus species form dense and often extensive colonies known as plum thickets. An example of one such large thicket for Chickasaw plum was described above.

Interesting (coincidentially or typical pattern?) these seedlings had emerged from last years fruits at exactly the time as this tree was in full bloom. All these pictures of Mexican plum were taken on the same day.

Erath County, Texas.

Plum good point: all the Prunus species furnish ideal habitat for several kinds of wildlife, especially northern bobwhite (Colinus virginianus). This same habitat when excessively large (ie. extensive thickets of several acres) constitutes a brush problem. The plums have become noxious species. This is true not only from perspective of livestock production but also of wildlife. Very large thickets of, say, several, acres are "too much of a good thing". They are too dense, for example, for easy movement (flight out of) by bobwhite and even more restrictive for deer. They are most restrictive to hunters and can interfere with game harvest. In addition, large plum colonies do not provide feed of higher palatability, digestibility, and nutrientive value to the extent that grasses and forbs do. More and smaller plum thickets (versus fewer and large, sprawling ones) make for superior range and wildlife habitat. More edege and total, useful cover is available with smaller yet a greater number of plum colonies. In fact, there is likely even more genetic diversity with more smaller-sized plum thickets simply because plum colonies are generally monoclonal (one genetic plant of many shoots).

Fire is the ideal way to keep plum thickets of more useful size. Fire was probably the major abiotic factor that keep plum thickets "in check" before the white man reduced fire regimes, especially fire frequency. Plum shoots are readily topkilled by fire of even moderate intensity. Subsequently, plum readily resprouts, but plum patchs are ususlly reduced in size after burning. "Burn out them plum thickets!".

Plum good time for another member of the rose family- Presented below were slide/caption sets of a hawthorn most closely fitting the description in Diggs et al. (1999, ps.941-943) of Reverchon's hawthorn (Crataegus reverchondii) on a post oak-blackjack- oak-little bluestem-Indiangrass savanna in the West Cross Timbers of northcentral Texas. Diggs et al. (1999, p. 942) noted on close resemblance of C. reverchondii to C. crus-gallii, cockspur hawthorn, concluding that C. reverchonii was "possibly not specifically distinct" from C. crus-gallii. Examination of herbarium specimen mounts online and various line drawings in manuals/florae revealed to this author's satisfaction that there was more morphological variation within each of these two species than between the two. For the northcentral Texas, including the Western Cross Timbers, Diggs et al. (1999, ps. 941-943) did distinguish between these two species as did Fernald (1950. ps. 775-776 pasim) and Steyermark (1963, ps. 808-810 passim) in their manuals and Sargent (1933, ps. 402-403, 523) in his encyclopedia of North American trees and Vines (1960, ps. 354-355, 359) in his illustrated classic. C. reverchondii does have pronounced obovate leaves. The specimens presented below principally had this feature so Reverchon's hawthorn it was.

This typically small tree and, sometimes, large shrub can become a local brush species. Reverchon's hawthorn is a native speccies, but under disturbance (and, especially, after initial affects of disturbance have been ameliorated) it can become a noxious range plant (ie. an invasive woody, a brush, species). Reverchon's hawthorn does provide covert cover (hiding space) for wildlife and thermal cover (shade) for wildlife and livestock. The fruit (a drupe) can be a concentrate feed for wildife. A sometimes inconvenient and bothersome morphological feature of Reverchon's hawthorn is spur-like thorns on its often-long leaders.

100. Shade cast (on the opposite side) by Reverchon- Young individual of Reverchon's hawthorn (Crataegus reverchondii) growing in a seepy microsite on a post oak-blackjack- oak-little bluestem-Indiangrass savanna in the West Cross Timbers of northcentral Texas.

Erath County, Texas. Late April.

101. Young leaves on lower limbs- Lower leaders on Reverchon's hawthorn with an array of leaf shapes on the same limb! These specimens were growing on the plant shown in the immediately preceding slide. It was growing in a shallow drainage in a post oak-blackjack- oak-little bluestem-Indiangrass savanna in the West Cross Timbers. Young leaves had he glossy, shinny, "brand-new" look before the ravages of summer heat and dryness calloused them to a duller, darker-green coloration.

Erath County, Texas. Late April.

102. In memory of Reverchon- Two sample leaders (branches) of Reverchon's hawthorn growing above a in a drainage in a West Cross Timbers post oak-blackjack- oak-little bluestem-Indiangrass savanna. Thorns are on both leaders. The glabrous, oval (more or less rounded) leaves that lacked shallow lobes were diagnostic of Reverchon's hawthorn.

Julien Reverchon was the first botanist to collect plants on an extensive basis in the area that is now the northcentral part of Texas (Diggs et al., 1999, p. 69). The famed dean of American dendrologists, Charles Sprague Sargent, named this Crataegus species in honor of this pioneer collector (Diggs et al., 1999, p. 942).

Erath County, Texas. Late April.

103. Reverchondrian leaves- Leaves of Reverchon's hawthorn in a West Cross Timbers savanna co-dominated by post oak and blackjack oak with little bluestem and Indiangrass as herbaceous co-dominant species. The color of these leaves is similar to that of green hawthorn (C. viridis), but leaves of green hawthorn have coarser teeth around their margins and frequently have shallow lobes (are widely cleft) on outer leaf edges. None of the leaves on the specimens presented here came anywhere near having such leaf margins.

Adult plants of Reverchon's hawthorn are quite attractive, especially when at peak bloom. These plants can become quite plentiful so as to also become a horrid pest. This species readily proliferates in the Western Cross Timbers, especially in low-lying moist environments such as draws and lower drainage areas, to become a serious noxious range plant. Reverchon's hawthorn is, of course, a native woody species with some value as a browse plant and even as an important bee plant. Fruit (a pome type) is a concentrate feed that is important to birds and smaller mammals such as furbearers. Such concentrated sources of energy and nutrients contribute to dispersal of this species by wildlife and, even, livestock.

Erath County, Texas. Late April.

Taxonomic note and warning: Crataegus is one of the most difficult of all North American plant genera to identify and arrange taxonomically for any number of reasons. More was written in this regard herein (farther below) while describing another Crataegus species. Frequent hybridization, apomictic and other formx of axexual reproduction, tremendous morphological variation (especially with regard to leaves and fruit) within a single species and among several species, and the comparatively large number of described Crataegus species make this one of the most complex, perplexing, and frustrating genera of North American range plants. Fernald (1950, p. 767) described the hawthorns as being "... of great taxonomic difficulty".

104. Not cock's spur, but maybe a chick's spur- Examples of thorns on Reverchon's hawthorn produced on a fairly small tree in a local area (microhabitat) of seepage (at least in a wet spring) in a post oak-blackjack- oak-little bluestem-Indiangrass savanna in the West Cross Timbers. One interesting phenomenon in these examples was presence of leaves growing along sides of thorns. This morphological feature was not shown in any of the line drawings presented by Sargent (1933, p. 523), Fernald (1950. p. 776) Vines (1960, p. 359), Steyermark (1963, ps. 810) or Diggs et al. (1999, p. 942).

One of the morphological characteristics used by Diggs et al. (1999, p. 941) to distinguish C. reverchonii from C. crus-gallii was "branches irregularly horizontal" versus "branches stiffly and uniformly horizontal" for these respective species. The first and second slides in this slide/caption unit showed some branches coming off of a larger or lower order branch at a more vertical orientation. This was seen as "irregularly horizontal", hence C. reverchonii once again (see other descriptions above).

Erath County, Texas. Late April.

105. Bur(r) or mossy cup oak (Quercus macrocarpa)- Young leaves and catkins of the dominant oak of the northern tallgrass, true, and mixed prairies northward from central Kansas. Bur oak can be interpreted as the northern ecological equivalent of post and blackjack oaks as the aboreal dominant of the grassland-deciduous forest ecotone (Vankat, 1979, p. 221). This species produces the largest acorns of any oak in North America and it is the oak of the famous oak groves and savannas of the northern grasslands (Peattie, 1938). Seedlings rapidly send their tap roots deep into the fertile prairie soils and become quickly established after germination (Weaver, 1968, ps. 135-139). This genetic adaptation to drought combined with the species’ thick fire resistant bark (Allen, 1967, p. 15) make it admirably suited to drought- and fire-prone prairies.

The species range of bur oak extends far south of its region of dominance into central Texas where it sometimes dominates bottomland savannas. Bur oak was placed at this point in the oak-hickory savannah to distinguish its region of dominance from that of post and blackjack oaks even though this specimen was growing as a minor component of the West Cross Timbers in Texas.Hamilton County, Texas, April.

106. Leaves and fruit of buroak- Burroak (either one or two "rs" are used) is regarded as having the largest acorn of any Quercus species in North America. Like other white oak species buroak bears fruit every year (versus a two-year cycle) in the red or black oaks. The combination of large acorns and production each year makes this species one of the most valuable producers of mast in the eastern deciduous forest (ie. the eastern part of North America).

Burroak is also known as mossy-cup oak, both common names in reference to the conspicuous tapered tips of the scales of the cup which present a fringe-like appearance. The geographic range of. Q. macrocarpa extends from eastern Canada (New Brunswick and Quebec) to Texas.

Hamilton County, Texas. September.

107. A Texas-size grape vine- A massive specimen of mustang grape (Vitis mustangensis) as a member of Cross Timbers vegetation on more mesic habitats. Mastang grape often develops into the forest or woodland (closed canopy) form of this savanna. This most complex or layer-rich structural expression of Cross Timbers sometimes includes a liana (woody training form) layer (a woody vine element that exends from the understorey to tree crowns). The most common woody vines or lianes in the Cross Timbers are various kinds of greenbriar (Smilax spp). Several of these Smilax species were included in the latter part of the Prairie Peninsula section below. Less frequently there are various grapes (Vitis spp.) that figure prominently in the architecture and botanical composition of the woodland subtype of Cross Timbers. These species "unite" lower and upper layers of the woodland subtypes of Cross Timbers.

An example of grape vines in the Western Cross Timbers was this specimen of river or streambank grape (V. riparia) that could only be described as "huge", "immense", "giant" or "Texas big". This twining behometh was growing on deep, moist, sandy alluvium along Alarm Creek, Erath County, Texas. November.

Some Cross Timbers grasses: The dominant Gramineae species of the Cross Timbers are those of the adjoining tallgrass prairies. These major species of grasses were presented in the chapter, Tallgrass Prairie. Some of the more common, dominant, valuable, or characteristic grasses of the Cross Timbers and/or Prairie Peninsula were shown in later parts of this chapter that dealt with the Prairie Peninsula. A few of the more common grasses growing on drier and/or ephemerally wet environments of the the Cross Timbers was offered as an "hors d'oeuvre".

Some of the more widespread grass species, including those of tallgrass savannas such as the Prairie Peninsula of the Central Lowlands and Ozark Plateau physiographic provinces, were presented later (below) in this chapter.

108. Tumblegrass (Schedonnardus paniculatus)- This widespread eragrostoid grass (tribe of Chlorideae) is one of the more distinctive common (often locally abundant) components of the herbaceous understorey of Cross Timbers. Tumblegrass produces remarkably limited forage because much of its biomass is in that portion of its shoot comprising the long curving inflorescence. On most range sites tumblegrass is an invader.

Western Cross Timbers, Erath County, Texas. April, anthesis to milky grain stage.

109. Green sprangletop (Leptochloa dubia)- A drought-stressed but quickly recovering specimen of green sprangletop managed to flower and sexually reproduce its kind at base of a pecan in Western Cross Timbers. Green sprangletop is capable of a lot of phenotypic plasticity. This is true not only across the diversity of habitats on which this perennial species grows but also for the same plant from one year to the next depending on specific growing conditions on a given microenvironment (eg. drought one summer, flood the next spring, early onset of cool weather the following autumn). The plant shown here had just recovered (or was in process of recovering) from a severe drought that had extended from mid-spring to late-summer). This individual had succeeded in putting forth some small inflorescences on short (hardly extended) culms.

Green sprangletop is an increaser on Cross Timbers range, but it is also a good producer of forage having Fair feeding value.

Erath County, Texas. October, early bloom stage.

110. Young flowering shoots and inflorescences of green sprangletop- Late summer shoots of green sprangletop that developed following soaking rains after a severe summer drought These late-season shoots were either stunted (or would appear as such) because there was not enough growing season remaining to permit development to normal mature size of sexually reproductive shoots in this species. Photoperiod was certainly a major factor in this regard, though the phenomena of photoperiod interacted with drought stress.

Green sprangletop produces cleistogomous spikelets enveloped within sheaths of basal leaves (ie. in effect, still in the boot). Cleistogamy is the condition in which flowers do not open normally so that any fruit produced is through self-pollination and self-fertilization. Cleistogamy existed in green sprangletop shoots shown in both of these two photographs. A clone, clonal unit, or ramet of one (the same) green sprangletop plant was shown in each of these slides. On each clone there were very short shoots that remained encased within a folded sheath and unopened blade of a single leaf (ie. the boot). These were present at the base and in front of the more obvious stunted shoot that was bearing an emergent inflorescence. Within the boots of these extremely short shoots there were "hidden"-- meaning unexerted-- inflorescences. Again, these shortest shoots were in front of both stunted shoots that bore newly emergening or exerted inflorescences (one shoot with an opening inflorescence in each of these slides). These "hidden" inflorescences were retained within the boot and these unopened racemes were bearing cleistogomous spikelets. The tips of these cryptic inflorescences were barely visible (appearing as pubescence) from tip of the boot (= folded leaf).

Erath County, Texas. Understorey of Western Cross Timbers. September. Again, two forms of the flowering stage of phenological development: 1) inflorescence emerging from the boot and 2) nonemergent or unexerted inflorescence (retained within the boot) bearing cleistogamous flowers.

111. Anthesis in green sprangletop- The distal portion of a green sprangletop inflorescence, the racemes--with young florets and their exerted anthers--of which were spreading or extending away from the rachis. This stage of floral development was a day or two advanced beyond emergence of the inflorescence from the boots on separate shoots as presented in the two slides immediately above.

Erath County, Texas. Understorey of Western Cross Timbers. September, anthesis.

112. Green sprangletop (Leptochloa dubia)- Large single plant of green sprangletop with several sexual (floral) culms plus several inflorescences (right foreground) of a second plant that was "off-stage". On shallow, rocky range sites in semiarid parts of the Edwards Plateau green sprangletop is usually regarded as a decreaser as it typically declines rather quickly on such harsh sites with heavy grazing (and, of course, overgrazing). Green sprangletop grows in association with sideoats grama, Texas cupgrass, Texas wintergrass, and silver bluestem or pinhole bluestem on mixed prairie savanna rangeland in the semiarid Edwards Plateau.

Green sprangletop can grow to mature heights exceeding three feet. The individual shown in this photograph reached two and a half feet and thus was an example of the habit and size of the larger form of this species. Other individuals of green sprangletop are considerably shorter and smaller overall, especially under heavier grazing. This example was growing on the Excellent condition Edwards Plateau live oak-mixed prairie savanna range described above.

On many range sites, including some sites of semidesert grassland, green sprangletop is regarded as an increaser. On various of the shallower, more xeric range sites in the semiarid Edwards Plateau green sprangletop has a response more like that of a decreaser.

Gould (1975, p. 226) described this eragrostoid grass as being strictly cespitose with neither stolons nor rhizomes, buth Hatch and Pluhar, 1993, p.99) ascribed rhizomes to green sprangletop and Silveus (1933, p. 368) implied the same.

Edwards County, Texas. October, immediate post-peak standing crop at grain-shatter phenological stage.

113. Inflorescence of green sprangletop- An inflorescence on the large individual green sprangletop featured in the preceding photograph. The common name of sprangletop refers to the spreading--hence, "sprangled"--arrangement of the inflorescence. Generically speaking the inflorescence of this member of the Eragrostoideae subfamily consist of numerous racemes on primary branches directly off of the rachis.

Edwards County, Texas. October, grain-ripe to grain-shatter stage.

114. One adapted to the Cross Timbers (and many other types)- Scribner's panicgrass or Scribner's rosettegrass (Panicum scribnerianum= P. oligosanthes var, scribnerianum) on an eroded microsite in the West Cross Timbers. The typically smallish plants of this species are widely adapted, especially to harsh environments and heavy grazing to which their low-growing feature and remarkable seed-set capability are well-fitted (as in survival of the fittest). Fitness as applied in evolution or genetic adaptation over time refers to those species (or other taxonomic ranks) that best preserve themselves through successful reproduction (ie. those organisms that leave the most progeny for continued existence in a given habitat or environment). Scribner's panic is a survivor, and a survivor over an extensive biological range.

Scribner's panicgrass is one of numerous Panicum species that are perennial, cool-season, C3 species that "overwinter" as a basal rosette. These rosette (hence, rosette-grasses) were included in the Dichanthelium subgenus of Panicum by Hitchcock and Chase (1950, p.638-680). Recent agrostologists such as those in Flora of the Greaat Plains (Great Plains Flora Association, 1986, ps. 1156-1163) and Barkworth (2003, p.406-450) in the definitive Flora of North America elevated Dichanthelium to genus status. Orthers such as Diggs et al. (1999, ps. 1291-1302) and Kaul et al (2006, ps. 691-695) retained the rosette panicgrasses in Panicum.

Erath County, Texas. Mid-April; pre-anthesis.

115. Spring fruit on degraded habitat-Several sexual shoots (first slide) and the terminal portion with panicle (second slide) of Scribner's panicgrass growing on a severely degraded microsite in the West Cross Timbers. The rosette panicgrasses (the Dichanthelium subgenus of Panicum) characteristically produce both vernal and autumnal flower clusters. This is part of a set of adaptations by which this species of little plants persist under adverse living conditions such as drought and overgrazing. (Of course it does not produce much forage.) Scriber's panicgrass is an increaser on most range sites, especially in the Cross Timbers.

Location Note: Other examples (different specimens) of Scribner's panicgrass were shown below in the Prairie Peninsula section along with other Dichanthelium members of Panicum. The specimen seen was included so as to be with other common members of the Crosss Timbers range community. Scribner's rosettegrass is such an abundant and widespread component of the Cross Timbers range type (SRM 372) that an "extra example" seemed appropriate. More details on the Dichanthelium panicgrasses were presented below.

Erath County, Texas. Mid-April; pre-anthesis.

116. Of two tribes- Thiinseed or fringeleaf paspalum (P. setaceum var. stramineum= P. setaceum), the grass with broader or wider leaves of lighter green color, inthe midst of (surrounded by) little bluestem in a tallgrass prairie/West Cross Timbers savanna transition in northcentral Texas. Thinseed paspalum is in the Paniceae, panicgrass tribe, while little bluestem is in the Andropogoneae, bluestem tribe. Thinseed or fringeleaf paspalum is the most abundant and widespread paspalum in this region. Various authors, including Gould (1975, ps. 523-526) recognized up to four varieties of P. setaceum, but Diggs et al. (1999, p. 1308) while making note of and listing these varieties were content to go no farther. So was the current author.

Thinseed or thin paspalum is best adapted to well-drained soils. It is reasonably tolerant of shade and heavy grazing but the low-growth form and relatively small size render this a species of low to, at best, fair forage plant.. In Texas Range Plants Hatch and Pluhar (1993, ps. 152-153) presented a concise description of thin paspalum, one of the species on the Texas Collegiate Plant Identification Contest. Another overall source of information was Lloyd-Reilley et al. (2003).

Erath county, Texas. Mid-May.

117. Almost too thin to see- Thin or thinseed paspalum shown as entire plant from basal leaves to inflorescence (first slide) and and with emphasis on basal leaves (second slide). These plants were growing in general area of West Cross Timbers on sandy soil in mid-spring. Erath county, Texas. Mid-May.

118. Leafy at their base- Basal leaves and culms of thinseed paspalum. Leaves of this species are wide and large in comparison to many other graas species that are associated with it, but these leaves are clustered so close to the ground that while this contributes to fairly high grazing tolerance it also reduces forage available to grazing animals, especially larger species like cattle, buffalo, and horses. Thinseed paspalum was regarded as of fair feeding value for livestock ((Lloyd-Reilley et al., 2003).

Erath county, Texas. Mid-May.

119. Narrow grain on a hybrid inflorescence- Views of the inflorescence with ripening caryopses of thinseed or thin paspalum that were produced on sandy soil in the subhumid zone. The Paspalum infloresecence was described by Chase (1937, p. 98; 1964, p.98) as "a panicle or of one to many racemes". These racemes (or racemose branches) are digitate (or racemose) on the central axis of this entire inflorescence. The various interpretations of the Paspalum inflorescence were given below in the section entitled Prairie Peninsula.

Erath county, Texas. Mid-May; nearing grain-ripe stage of phenology.

120. Skinny grains on sand- Spikelets/florets of thinseed or thin paspalum produced on sandy soil of a tallgrass prairie/West Cross Timbers transition. Paspalum species are in tribe, Paniceae, in which spikelets consist of a perfect terminal floret that is subtened by (above) a sterile floret. The first glume "is wanting" (ie, onexistent or absent) in Paspalum species and their spikelets are "plano-convex" (Hitchcock and Chase, 1950, p. 25). The spiklets (and caryopses) are noticeably thinner (therefore, "thinseed") than those of other paspalums. Spikelets (grains) occur in two rows along (one row on each side of) the raceme or racemose branch.

Erath county, Texas. Mid-May; nearing grain-ripe stage of phenology.

121. See any hairs; see much of anything?- Part of a local stand of hairy grama (Bouteloua hirsuta) growing in the West Cross Timbers with post oak as local dominant. Hairy grama is not typically a dominant or even associate species in the Cross Timbers, but it is common and widespread in this range type.

Erath County, Texas. Late October; peak anthesis stage of phenology.

122. Now see this- Racemes of hairy grama loaced with spikelets at full flower. Erath County, Texas. Late October; peak anthesis stage of phenology.

66. Hairy base- Basal shoots of hairy grama in early spring on a shallow, calcareous soil in the Grand Prairie in northcentral Texas. Both last year's and current year's (green) shoots were present on this ungrazed plant. Standard references for hairy grama in Texas ranged through a rather long long list of historic manuals or floras including Coulter (1891-1894, p. 531 as B. hirta), Silveus(1933, ps. 427, 434), Gould (1975, ps. 353-354), Correll and Johnston (1979, p. 245), Powell (1988, p. 214), Diggs et al., (1999, ps. 1248), and Shaw (2012, p 340 as Chondrosum hirsutum).

Hairy grama is one of the most important range grasses over much of the mixed prairie and in portions of the Edwards Plateau and Rio Grande Plains savannas as well as being locally important in the Cross Timbers and associated tallgrass prairies, on these latter grasslands hairy grama is mostly limited to shallow rocky sites as in the Flint Hills of Kansas (Weaver, 1954, p. 66). This species importance was obvious by inclusion of hairy grama as one of the 200 plant species on the International Range Plant Identifiction Contest sponsored by the Society for Range Management (Stubbendieck et al., 1992, ps. 84-85) and on the Texas Range Plant Master List for 4-H and Future Farmers of America range and pasture contests held in the Lone Star State (Hatch and Pluhar, 1993, ps. 64- 65).

As is the case with most range grasses, general coverage of hairy grama typically has been in regard to taxonomy, and morphology related thereto, with relatively little treatment as to ecology and management (or even basic natural history) of this eragrostoid grass. Discussion in Phillips Petroleum Company (1963, p. 21) is always reliable and appropriate including the summary that hairy grama "is one of the most nutritious of the grama grasses and is readily eaten by all classes of livestock", and that this species is generally an Increaser on overgrazed tallgrass prairie ranges. Tyrl et al. (2008, ps. 64-65) provided one of the more detailed treatments of hairy grama (and the drawings therein by Jansen are without peer). Hairy grama is a climax decreaser on certain range sites in mixed prairie and shallow, rocky range over much of the Edwards Plateau. Hairy grama is adapted to both shallow, stony habitats as well as those of sandy soils (Weaver and Albertson, 1956, p. 60).

Tarleton State University Hunewwell Ranch, Erath County, Texas. Mid-April; last year's dead herbage; early spring greenup for current season.

Taxonomic Musical Chairs: Powell (1988, p. 206) summarized the following at-that-time-recent development in grass systematics. First, Gould (1979) made the case for two Bouteloua subgenera: 1) Bouteloua and 2) Chondrosu(i)m. Next, Clayton and Renvoize (1986) elevated the two subgenera of Gould (1979) to the new genera of Bouteloua and Chondrosum. Powell (1988, 206-220) did not accept Chondrosium as a genus and retained all former Bouteloua species. In Flora of North America Barkworth et al. (2003, ps. 250-269), used the two subgenera (Bouteloua and Chondrosu(i)m) of Gould (1979), but retained genus, Bouteloua.

Subsequently, Shaw (2012, ps. 263, 334-335), Gould's protege, followed Clayton and Renvoize (1986) and, in the most recent (up to this time) treatment of Texas Gramineae, sub-divided genus Bouteloua into Bouteloua and Chondrosum. Thus, Texas grama remained Bouteloua rigidiseta (Shaw, 2012, p. 273) whereas hairy grama (formerly B. hirsuta) became Chondrosum hirsutum (Shaw, 2012, p. 340).

Allrd and Ivey (2012, p 638) remarked that some authors had split Bouteloua into Bouteloua and Chondrosum; they then cited work out of Rancho Santa Ana Botanic Garden, California that "have shown this to be untenable." While the author of Range Types of North America is not a plant taxonomist and, therefore, not entitled to a professional taxonomic judgment, he nonetheless followed the traditional, still-mostly-accepted nomenclature and the contemporary rejection of this division of Bouteloua. For that reason, the historic, and, still predominately accepted, genus of Bouteloua was shown herein for the gramas (grama or gramagrass species). Readers were, however, alerted as to the newer changed name of some Bouteloua species in some work (eg. latest manual for Texas grasses).

Close (and taller) relative- Sexual shoots and racemes of tall grama (Bouteloua pectinata) that grows in the same habitat (slightly different niches) as hairy grama. In fact, tall grama was historically interpreted as merely a form of hairy gram until Featherly (1931) distinguised them as separate species. Some agrostologist persist in this by diesginating tall grama as a subspecies of hairy grama (eg. Shaw, 2012, p. 340). In this instance (eg. Shaw, 2012, p. 340) elevated the section, Chondrosum of Hitchcock and Chase (1951, p. 533) to its own genus of Chondrosum so that tall grama became C. hirsutum subsp. pectinatum. The author who took this photograph rejected the interpretation of Shaw (2012) and stayed with Featherly (1931) so B. pectinata it is.

Tarleton State University Hunewell Ranch, Erath County, Texas. Early September.

Time for a little disturbed one- Plant of Texas grama (Bouteloua rigisdeta) on a degraded microsite in a patch of Grand Prairie in the West Cross Timbers. In this range region this Texas grama is the smallest Bouteloua species and the one best adapted to aabused habitats like overgrazed range. it is a cool-season (more like opportunistic) species. It's main function is to do its part to hold the Earth together. Texas grama is an invader, but it helps set the stage for the next seral stte (hopefully).

. Tarleton State University Hunewell Ranch, Erath County, Texas. Mid-April.

123. Carolinian in Texas- Carolina canarygrass or wild canarygrass (Phlaris caroliniana) growing on a feedground in the West Cross Timbers of northcentral Texas. This typically short-statured, wide-leaved annual member of the Aveneae, oat tribe, is native to grasslands, savannahs, and open forests. Annual grass species that are native are relatively uncommon in the tallgrass country and adjoining savannahs like the Cross Timbers and Post Oak Savanna so it seemed appropriate to include this example.

It would seem likely that a cool-season, annual grass with broad leaves (think Avena species for instance) would be relatively palatable, but such is basically not the case for Carolina canarygrass. In fact, Carolina canarygrass can be toxic to livestock by inducing neurological disorders, often several weeks up to months following forage consumption Nicholson et al (1989). From standpoint of forage (feeding) value there appeared to be a dearth of data in regards to nutrient content, but brief published analysis showed immature herbage of P. caroliniana to be of generally lower Crude Protein concentration and similar energy content (Digestible Energy, Total Digestible Energy) as compared to immature herbage of the much larger P. arundinacea (National Academy of Sciences, 1971, ps. 172-173). Medicore nutritive value coupled with small size (low levels of herbage yield) make Carolina canarygrass an undesirable forage species. (Maybe it is good feed for rabbits and rodents.)

Carolina canarygrass is simply another grass species that is frequently encountered on disturbed areas (such as that shown here) in the Cross Timbers and associated grasslands. With its comparatively large--especially, wide--leaves and prominent contracted panicle Carolina canarygrass can be an eye-catching plant. Hence, this dimunitive species was included at this point.

Erath County, Texas. Late April; anthesis.

124. Blooming cluster-Several apical parts, including inflorescences (contracted panicles), of sexual shoots of Carolina canarygrass. These shoots complete with panicles had been produced by plants growing on a hay-feeding ground (shown immediately above) in the West Cross Timbers.

Erath County, Texas. Late April; anthesis.

125. Sex in canarygrass- Upper portions of sexually reproductive shoots of Carolina canarygrass (first slide) with details (second slide) of inflorescence (contracted panicle), flag leaf, and leaf that subtended (was below) the flag leaf. Later stage of anthesis. Flowering in the Gramineae is determinate, exertion of stamens and styles progresses from top and outside of flower cluster downward and inward, respectively. At time of these photographs anthesis was taking place toward lower portion of the contracted panicle indicating that flowering in this plant was in a more advanced stage of anthesis.

Carolina canarygrass is in the oat tribe, Aveneae.

Erath County, Texas. Late April; anthesis.

126. Panicle and flag leaf- Two views of the contracted panicle of Carolina canarygrass showing details of the flag leaf which had been the boot, the leaf that enclosed the unexerted panicle prior to its appearance and subsequent anthesis. This panicle was in early anthesis, an obvious fact because grasses are determinate bloomers with anthesis progressing from top to bottom and outside (exterior or perimeter) to inside (interior) of the flower cluster. Anthesis in this panicle can be compared to that in the panicle seen in the immediately preceding slides which was in earlier or less advanced stages of anthesis.

Carolina canarygrass is an annual so that yearly seed (grain) production is part of the reproductive pattern of this small, native grass.

Erath County, Texas. Late April; anthesis.

127. Another annual in the Cross Timbers- Little barley (Hordeum pusillum) growing on a locally disturbed microhabitat in the West Cross Timbers in northcentral Texas. Little barley is a native annual grass, an unusual combination of features for grasses in the Cross Timbers which is a oak-hickory-perennial tallgrass savanna. In years where there was a wet winter-spring period little barley can be locally abundant.

Given its tremendous species range, nativeness, annual life cycle, and local commonness little barley was included on the list of 200 plant species for the Society for Range Management (SRM) International Range Plant Identification Contest (Stubbendieck et al., 1992). Little barley is also included in the Texas Intercollegiate Range Plant Identifiction Contest sponsored by the Texas Section, SRM as well as on both the range plant list for Texas 4H and Future Farmers of America Contests (Hatch and Pluhar, 1993).

Little barley is classified as an invader what with being an annual--even if a native one--on range where almost every one of the dominant plant species is a perennial. Little barley typically invades disturbed areas such as overgrazed ranges and "go-back land" where it undoubtedly provides some soil protection against the agents of soil erosion. A concise yet informative description of little barley, including practical aspects, was in both editions of Pasture & Range Plants (Phillips Petroleum Company, 1963; Nicholson, 2006), although the author of Range Types disagreed that little barley is "essentially worthless" for livestock and wildlife. In point of fact, this short-statured species sometimes provides forage for cattle, sheep, horses, and deer. On dormant tallgrass prairie where the herbage of bluestems, Indiangrass, sideoats grama, etc. is weathered after three months of dormancy this C3, festucoid grass frequently provides some green feed--the quantity varying substantially--thart is richer in carotene, higher in crude protein, and better in flavor than that in the herbage of the decreasers and increasers. This could be especially to the smaller ruminant species.

Hunewell Ranch, Tarleton State University, Erath County, Texas. Mid-April; anthesis.

Location Note: more examples and descriptions of little barley as well as other native annual grasses were included in Range Types of North America in the chapter, Tallgrass Prairie (Interior)-IB.

128. One adapted for dry or disturbed ground- Red lovegrass (Eragrostis secundiflora subsp. oxylepis= E. oxylepis= E. beyrichiii) on local disturbed patch on a transition between tallgrass prairie and West Cross Timbers savanna. This ecological invader is widespread on denuded land, waste places, old fields in earlier stages of secondary succession, overgrazed range, and so on. This grass is so common in Texas that it was included in the reference, Texas Range Plants (Htch and Pluhar, 1993, ps. 92-93).

Forage value and even soil protection qualities are poor for this small, cespitose perennial. The author's mother always instructed her son thusly, "If you can't say something nice and pleasant about someone just don't say anything". When it comes to red lovegrass the speaker's son remarked that red lovegrass has "cute spikelets". Next two slides.

Erath County, Texas. Mid-May; anthesis.

129. Cute, colorful spikelets- Spikelets in panicle of red lovegrass. These spikelets were on one of the plants presented in the preceding two slides. Spikelets (and florets) of red lovegrass are substantially larger than those of other Eragrostis species. Erath County, Texas. Mid-May; anthesis.

130. Grasslike in the company of grasses- Grass-leaf, two-flower, or needle-point (Juncus marginatus) growing on a transition zone between West Cross Timbers and Grand Prairie grassland. This species was growing on the same range as that on which red lovegrass, little bluestem, thin paspalum, Scribner's panicgrass or Scribner's rosettegrass, fall witchgrass (Leptoloma cognatum), and a number of forb species including old plainsmen (Hymenopappus scabiosaeus var. corymbosus), Mat bluets (Houstonia humifusa), prairie fleabane (Erigeron strigosus), and diamond-point or four-pointed evening-primrose (Oenothera rhombipetalaa).

Location note: many of the forb species just listed were included below under (or at end of) the Prairie Peninsula section that concluded this Tallgrass Savanna chapter. This arrangement was used because these forbs are widely distributed throughout the ecotone between tallgrass prairie and oak-hickory forest formations. By contrast, range plant species such as Juncus. marginatus, J. brachyphyllus, Phlaris caroliniana Eragrostis secundiflora subsp. oxylepis are more restricted in their species ranges within this vast ecotone between grassland and deciduous forest that extends from the Texas Cross Timbers northward into the bur oak (Quercus macrocarpa) groves of southern Canada.

Erath County, Texas. Mid-May; early fruit stage of phenology.

131. Small parcels but heavy heads- Fruit (loculicidal capsule)-laden inflorescences of grass-leaf rush, two-flower rush or needle-point rush produced on a transition zone between tallgrass prairie and the savanna of a blackjack oak-post oak-herbaceous plant community in the West Cross Timbers in northcentral Texas.

Palatability of Juncus species, even allowing for varability within this genus, is generally regarded as low for livestock and native ruminants. Furthermore, herbage yield and overall availability/abundance of these grasslike plants is much less than that of associated grass and forb species such that the rushes (Juncus spp.) provide little by way of feed to range animals, other than on a restricted (very local) bsis. Nonetheless, these graminoids are part of the range plant community and, given that they are natural components of their range ecosystems, it makes no sense (and is the height of ecological arrogance and naivete) to ignore them. Carry on little rush!

Erath County, Texas. Mid-May; early fruit stage of phenology.

132. Small and short where no shortage of sand- Small-head rush or short-leaf rush (Juncus brachyphyllus) growing on a Sandy range site in the West Cross Timbers. The soil was a Selden fine sand that has "mixed conclave and convex surfaces" with "sandy clay loam lower layers" ((Soil Conservation Service, 1973, sp. 30-31).

This three-slide sequence presented small-headed rush at progressively closer distances with two different plants presented in the first two slides while the third slide was of the largest inflorescence on the plant in the first slide. The microsite on which these plants grew was one that due to microtopography ponded water for extended periods (at least during wet periods). Blunt spikerush (Eleocharis obtusa) was the closest neighboring species to these plants of short-headed rush.

There are numerous Juncus species in the Cross Timbers and adjoining prairies of northcentral Texas (Diggs et al., 1999, ps. 1179-1186). Many of these are next to impossible to identify due to incomplete collections of plants at different phenological stages, a necessary array of specimens for positive identification. The inflorescence of J. brachyphyllus is real distinctive with its spreading pattern of densely crowded yet solitary capsules makes field identification of this species relatviely easy (at least when plants are in fruit-producing stages of phenology). The latter capsule features were presented in the last two slides devoted to this species.

Tarleton State University Hunewell Ranch, Erath County, Texas. Mid-April; growing capsule-stage of phenology.

133. From deep sand- Sexual shoots (first photograph) and inflorescence (second photograph) of small-head or short-leaf rush on Sandy range site where an irregular land surface ponded water for brief to extended periods (depending on rainfall) in the West Cross Timbers. The plants on which these shoots had developed were growing near a dense population of blunt spikerush (Eleocharis obtusa; see below) that also liked mesic edaphic environments.

There had been only minor defoliation, which appeared to have been by white-tail deer (Odocoileus virginianus), of small-head rush plants at this location.

Tarleton State University Hunewell Ranch, Erath County, Texas. Mid-April; growing capsule-stage of phenology.

134. Clusters of capsules- Two views of maturing capsules of short-leaf or small-head rush produced on a Sandy range site in the West Cross Timbers. Single flowers/capsules in a crowded arrangement is a good identifiying feature of this species of grasslike plant.

Tarleton State University Hunewell Ranch, Erath County, Texas. Mid-April; growing capsule-stage of phenology.

135. Lined sedge or eastern woodland caric sedge (Carex blanda)- One of the more common and widespread caric sedges in the Texas Cross Timbers. Although there are several species of Carex and Cyperus in the post oak-blackjack oak-pecan savanna designated Cross Timbers most of these are incidental and any abundance, let alone dominance, is local. Carex striatula is somewhat of an exception to this general rule. While any appreciable dominance by lined sedge is local, this species is common enough in distribution, especially in the Texas' West Cross Timbers, that it should be regarded, at least in part, as an important and defining/distinguishing) species.

In his monographic treatment of the West Cross Timbers vegetation Dyksterius (1948) did not list this Carex species. In fact he listed only one which is generally distributed more in eastern portions of the West Cross Timbers.

These plants were growing near base of a pecan.

Erath County, Texas. April.

136. Flowering in lined cric sedge- Sexual shoots of Carex blanda showing staminate and pistillate inflorescences at anthesis. These shoots were on the plants introduced in the immediately preceding photographs.

Erath County, Texas. April.

137. A species of larger plants- A plant of Muhlenberg's bracted sedge, Muhlenberg's caric sedge, bracted sand sedge, or sand sedge (Carex muhlenbergii) growing on a sandy bottomland habitat in the West Cross Timbers of northcentral Texas. Individual plants of this Carex species frequently grow to comparatively immense size in contrast to many other Carex species such as C. blanda presented immediately above. Specimens seen here and in the next two slide sets were C. muhlenbergia var. muehlenbergii based on Diggs et al. (1999, p.1128).

Muhlenberg's caric sedge grows in varied habitats, but it usually requires sunny or well-lite environments: obligate to facultative sciophyte (Diggs et al., 1999, p. 1128). The individual shown here and plant parts presented in the next two succeeding sets were growing on a sandy bottomland at the edge of a closed canopy stand of West Cross Timbers dominated by post oak (Quercus stellata). The major associated herbaceous species were little bluestem, yellow Indiangrass, and Texas wintergrass.

Hunewell Ranch, Tarleton State University, Erath County,.Texas. Mid-April; maximum plant biomass and development (immature achene) stage of phenology.

138. Bottoms and tops- Shoot bases, including root crowns, (first slide) and leaves along with sexual shoots (second slide) of Muhlenberg's caric sedge in the West Cross Timbers. Although typically cespitose, Muhlenberg's caric sedge frequently has rhizomes which gives plants a somewhat of sod-forming appearance and contributes to their often large size.

Hunewell Ranch, Tarleton State University, Erath County,.Texas. Mid-April; maximum plant biomass and development (immature achene) stage of phenology.

139. Closer views of tops- Two views of the spike inflorescence and morphology of spikelets of Muhlenberg's caric sedge or bracted sand sedge produced on a sandy bottomland habitat in the West Cross Timbers. This crop had been produced in a particularily wet late winter and spring.

Hunewell Ranch, Tarleton State University, Erath County,.Texas. Mid-April; immature achenes (mostly milk to soft dough stage).

140. A nother genus of Cross Timbers grasslike plants- Blunt spikerush (Eleocharis obtusa) growing on a microsite that ponded water during brief wet periods in the West Cross Timbers. This local population of the annual blunt spikerush was thriving--even if ever so briefly--on a localized deep sand microhabitat of a Sandy range site.

There are both annual and perennial Eleocharis species. In northcentral Texas where these plants of E. obtusa were growing there are 15 Eleocharis species, six of which are annuals. Almost all of the perennial Eleocharis species are rhizomatous and form expansive clonal colonies. As shown here E. obtusa growns in local populations made up of very dense cespitose genotypes.

Hunewell Ranch, Tarleton State University, Erath County,. Texas. Mid-April; mature achenes.

141. Gone to seed on wet microsite- Sexual shoots of blunt spikerush with spikes filled full of achenes. These shoots were produced on a local water-ponded microsite in the West Cross Tiimbers. Blunt spikerush is an annual cespitose species. It therefore requires sexual reproduction to persist from one growing season (year) to the next. Nonetheless, blunt spikerush also reproduces asexually through growth of many tillers, all of which are secondary shoots (except for the seedling or primary shoot) and, thus, clones of the original (seedling) genotype. In this way, the annual blunt spikerush "keeps its options open" using both sexual and asexual regeneration. Sexual reproduction with recombination of genes permits on-going adaptation (evolution) of blunt spikerush to its range environment. Asexual reproduction (tiller production) and plant growth are one and the same with this pattern.

Hunewell Ranch, Tarleton State University, Erath County,. Texas. Mid-April; mature achenes.

142. Wetland plant? Not me!- Two typical specimens of slender or Great Plains flat-sedge or umbrella sedge (Cyperus lupulinus) growing on dry, sandy soil in the West Cross Timbers of northcentral Texas. Great Plains umbrella- or flat-sedge is one of the Cyperus species best adapted to relatively xeric habitats in this region. Most Cyprus species are best adapted to moist up to wet soil environments such that many are wetland plants. Great Plains flat-sedge has more nearly the opposite adaptations.

Slender flat-sedge is a member of range plant communities of the Cross Timbers ranging from post oak-blackjack oak-tallgrass savannahs and, even, mixed oak-pecan forests to drier, shallower grasslands to sand post (margaretta) oak dwarf forests.

It was observed by this photographer that individual plants of Great Plains flat-sedge grew to larger sizes in the savanna than in the margaretta oak- pygmy forest communities. In some localities this relative difference was drastically (ie. dramatically smaller on the margaretta oak-dominatee "sandrough".

Erath County, Texas. Early September, immature-fruit stage of phenology.

143. One for the dry sands- A third specimen (counting the preceding two plants) of slender of Great Plains umbrella-sedge (first slide) and a detailed view of some of thhat plant's sexual shoots (second slide) produced on dry, sandy soil during a relatively dry and characteristically hot summer in the West Cross Timbers. This is one of the Cyprus species that is best adapted to more xeric microsites in the Western Cross Timbers.

Erath County, Texas. Early September, immature-fruit phenological stage.

144. Flat out on sandy soil- Two inflorescences (panicles) with prominent spikelets on shoots of slender of Great Plains flat- (= umbrella-) sedge. This fruit was produced by plants growing on dry, sandy soil during a relatively dry and (always) hot summer in the Western Cross Timbers of northcentral Texas.

Erath County, Texas. Early September, immature-fruit phenological stage.

124. Touch at your own peril- Two views of a robust specimen of Texas bull-nettle, spurge-nettle, or tread-softly (Chidoscolus texanus). This member of the spurge or croton family (Euphorbiaceae) is a perennial with an extremely large taproot and an extraordinary drought tolerance. (The large root is edible, by the way.) The most distinguishing or sometimes and, unfortunately, memorable feature of this range plant if one brushes up against it (or cluelessly touches it) is the long-lasting stings imparted by numerous of trichomes (large, needle-like, poisonous or toxic hairs) with which this monster is armed. This physiological condition is known as contact urticaria, from Urticaceae, the sting-nettle family (Diggs et al., 1999, p. 598). Early chemical analysis of extracts from the trichomes showed presence of serotonin and perhaps as-yet unknown compounds (Lookadoo and Pollard, 1991).

Texas bull-nettle is generally observed to do best on disturbed habitats such as old fields (abandoned farmland), road cuts, and overgrazed pastures. Deep often moist, sandy soil provides an ideal environment for this deep-rooted, drought-tolerant native range forb (Johnston and Warnock, 1963, p. 126). Openings sanannahs of Cross Timbers with tallgrass species and, especially, edges where Cross Timbers and tallgrass prairie of the Grand Prairie "collide" provided similar ideal environments, particularily at local scale, for Texas bull-nettle.

Erath County, Texas. Mid-May; peak bloom stage, maximum shoot size.

125. Flowers and fruits amid stings- Infloresecence (first slide) and fruit (second slide) of Texas bull-nettle or spurge-nettle in the West Cross Timbers. Texas bull-nettle has the standard euphorb-type inflorescence of the Crotonoideae or Euphorboideae subfamily with opened and unopened flowers (again, first slide). Texas bull-nettle is monecious with separate male and female flowers in the flower cluster (Diggs et al., 1999, p. 598). The flowers in this slide were staminate (male). Fruit type of Texas bull-nettle is a capsule (Correll and Johnston, 1979, p. 955; Diggs et al., 1999, p. 598). Several capsules on the sexual (fruit-bearing) apical shoot of Texas bull-nettle were shown (second slide).

For all of its remarkable, unusual, and, sometimes, "sensational" features Texas bull-nettle has apparently received little study. Brief botanical descriptions such as that in Diggs et al. (1999, ps. 596, 598) are about the extent of thorough treatment. Another brief description was that of Johnston and Warnock (1963, ps. 124-126) as was that in the "bible" of Texas plant species, Manual of the Vascular Plants of Texas (Correll and Johnston, 1979, ps. 954-955).

Erath County, Texas. First slide: Mid-April. Second slide: Mid-May.

126. Christmas in the summer- Summer or wild poinsettia or, sometimes, painted spurge (Euphorbia cyanthophora= E. heterophylla var. cyathophora) growing on recently disturbed soil in an open grove of post oaks in the West Cross Timbers of northcentral Texas.As seen in these two slides wild poinsettia prefers disturbed soil. It appears to be a pioneer spceies of the first or second seral stages.

In the West Cross Timbers this plant typically grows to a stature of two foot or less. In humid areas it can reach heights in excess of three feet under natural conditions. The author's mother grew summer poinsettia in her flower garden in northeastern Oklahoma where, with routine watering, plants reched heights of over four foot. Wild poinsettia is an annual species and they were self-seeding in Mom's garden for a number of years. The young summer poinsettias, especially seedlings, were also quite palatable to cottontail rabbits (Sylvilagus floridanus) which after trouble-free years eventually became a plague on Mom's wild poinsettia. Thereafter, it was war on bunnies every spring.

Like Texas bull-nettle featured immediately above, summer poinsettia is a member of the Crotonoideae or Euphorboideae subfamily of Euphorbiaceae (croton or euphorb family). Wild poinsettia has a milk-colored (latex) sap, and it is toxic though apparently less so than E. marginata, snow-on-the-mountain, and E. bicolor, snow-on-the-prairie (Hart et al., 2003, p. 94).

Animals usually avoid eating this species, except in certain cases where, as explained above, cotton-tail rabbits found them delectable in Mom's flower garden. The summer poinsettias did contribute to death of some rabbits, but it was due to "lead-poisoning" from Pop's Stevens .22 rifle. Your author was ultimately compelled to string up chicken wire to protect the summer poinsettias (and rabbits). Then several (perhaps a family of) five-lined or eastern chipmunk (Tamias striatus) moved on the summer poinsettia gaining entry through mesh of the poultry net wire. So the author placed heavy rocks over (in front of) the spaces in the poultry netting. Chipmunks burrowed under the rocks and poultry wire and ate the remaining, resprouted shoots of summer poinsettias. Chipmunk feeding continued until all the wild poinsettias died. Such is life on the range.

This unplanned de facto experiment demonstrated that summer poinsettia is 1) palatable but 2) not toxic to lagomorphs and rodents at rates they consumed it.

Erath County, Texas. Late September, peak phenological development including current flowering.

127. Cross Timbers poinsettia- Three progressively closer views of summer poinsettia growing on a disturbed site in close proximmity to post oaks in the West Crss Timbers of northcentral Texas. Given its similarity to the Christmas poinsettia of commerce (E. pulcherrima) and its toxicity to range animals, the native summer poinsettia was found to be interesting to your author and, hence, was included here.

Wild poinsettia is a naative forb that is representative of Cross Timbers vegetation. It contributes to biological diversity (and probbly to diets of cottail-tail rabbits).

Erath County, Texas. Late September, peak phenological development including current flowering.

126. A Texan that takes to sand- Texas groundsel or Texas ragwort (Senecio ampullaceus) growing on the deep sandy soil of a Bottomland range site in northcentral Texas. Texas ragwort is a cool-season annual. The clasping leaves that partially encircle the stem is a characteristic feature of this native composite that is in the aster tribe (Astereae). The plant seen here was growing at edge or local ecotone of a bottomland forest and tallgrass prairie in the Cross Timbers and Prairies vegetational (land resource) area. This individual specimen was one of a large local population as was visible in background of the first or upper slide.

Erath County, Texas. Early May; full-bloom and fruit shatter phenological stages.

127. Heads on the sand- Inflorecences of Texas ragwort or Texas groundsel with a top-down view of a flowering individual in the first or upper slide and a closer view of a unit of the flower cluster consisting of several heads in the second or lower slide. These examples were on plants that were part of a local population of this cool-season annual composite (placed in the aster tribe) that was growing on a Bottomland range site of deep, alluvial sand in the Cross Timbers and Prairies land resource (vegetational) area of northcentral Texas.

Erath County, Texas. Early May; full-bloom and fruit shatter phenological stages.

128. Spent heads, ready-to-fly fruits, and flew-the-coop fruits- Flowers and fruit of Texas ragwort or Texas groundsel with some capitula (heads) just finished flowering and progressing to fruit stage, a head of achenes with their litttle "parachutes" waiting to be dispersed by wind, and an empty disk with winged achenes already dispersed.

Erath County, Texas. Early May;late--bloom and fruit shatter phenological stages.

129. Angus aphids and ants wort grounded- Reclusive black aphids and attracted ants were crawling rapidly about the clusters of heads of Texas groundsel or Texas ragwort growing on a Bottomland range site of deep river alluvium in the Cross Timbers and Prairies vegettional area of northcentral Texas. It was not known if ants were tending the aphids or simply attracted to the aphids by their honeydew. In other words, it was not known if this symbiosis was a form of mutualism (dual benefit with aphids getting some protection and ants getting the rich insect "nectar") or merely opportune commensalism (ants getting the benefit of a rich nutrient source "for free"). Typically this interspecies insect relationship is mutualistic, but in the scurry (these insects were unimaginatively evasive being both fast and secretive) of this mixed herd feeding it was hard to determine exact nature of the interrelationship.

Honeydew is the excreta of aphids that in composition is primarily surplus sap eaten and excreted out the anus of aphids with additioanl sugars and other waste products included (Borror and Delong, 1954, p. 264). Honeydew is often a choice feed of certain ant species. Both of these insect species were extremely wary of the photographer and the mixed herd (first slide) broke like a covey of quail and quickly hid behind amid plant parts (second slide). Unappreciative little farts.

Erath County, Texas. Early May.

130. Gold with autumn bluestem- Narrowleaf or stiffleaf gold-aster (Heterotheca stenophylla) is one of a "gazillion" composites in the Cross Timbers. For example, even in the small Heterotheca genus there are three species in Crosss Timbers vegetation in northcentral Texas. Heterotheca stenophylla is a perennial that prefers sandy soils (Diggs et al., 1999, p. 372). This happily blooming specimen was growing amid a local, relict community of little bluestem and Indiangrass that had been spared tillage and overgrazing.

Eastland County, Texas. Mid-October: and obviously at full-bloom phenological stage.

131. Pin cushion on the prairie- Pin cushion daisy (Gaillardia suavis) on the edge of a tallgrass prairie in the Grand Prairie adjoining the Western Cross Timbers in northcentral Texas.Pin cushion daisy is another member of the vast tribe, Heliantheae. G. suavis is a perennial that often grows in dense local populations, but it is much less common than its close relative, Indian blanket (Gaillardia pulchella) which is an annual characteristically growing in extensive populations on disturbed habitats, in particular old fields (abandoned farmland).

The strictly basal leaves and tall, bare (devoid of leaves) flowering shoot are very distinctive, and make a neat photographic subject. This morphological feature is known as scapiform (see next photogrphic caption).

Erath County, Texas. peak standing crop, full-bloom phenological stage.

132. Pinned on the prairie- Plants (upper or first photograph) and capitulum (second or lower slide) of pin cushion daisy on edge of tallgrass prairie and a tract of oak-tallgrass savanna (an ecotone of Grand Prairie and West Cross Timbers). Pin cushion daisy was described as scapiform, an adjective referring to the scape which is a leafless flowering stem that extends from ground level to inflorescence (Great Plains Flora Association, 1986, ps. 939, 1325).

Erath County, Texas. peak standing crop, full-bloom phenological stage.

Wheels afire- Local, dense population of the annual composite commonly called firewheel (Gaillardia pulchella) growing on an old field (go-back land) ion the West Cross Timbers. This is one of the showier species of "weed" or "wild-flower" in Cross Timbers savanna and grasslands of the Grand and Fort Worth Prairies.

Firewheel is a pioneer or first-year colonizing species on abandoned fields and recently disturbed sites such as rights of way following road construction. Many annual forbs are not just weeds, but also look like look weeds. Firewheel is not a weed of this category. Ecologically speaking firewheel is a weed (and like all weeds it plays a vital role in secondary plant succession leaving the "weed" distinction open to debate), but it clearly also looks like and, in the minds of many folks, is a brightly colored "wildflower". In other words, firewheel is "weedy", but it ain't.

Erath County, Texas. late May; peak bloom stage.

133. Fine forb for disturbance- Texas filaree or Texas stork'sbill (Erodium texanum) is a native annual of the Geraniaceae that thrives on harsh microsites in range types ranging from tallgrass prairie such as the Grand Prairie, Crosss Timbers savanna, to Edwards Plateau. The examples seen here were growing on an overgrazed (but recovering) range in the West Cross Timbers.

This little annual does not produce much forage, but it is quite palatable to small ruminants such as sheep, goats, and white-tailed deer. Cattle and horses also eat it though with less preference.

Tarleton State University College Farm, Erath County, Texas. Late April.

134. Annual forb on degraded savanna- Texas stork'sbill or Texas filaree at both peak-bloom and immature fruit phenological stages. This plant was on a a degraded range in the West Cross Timbers.

Tarleton State University College Farm, Erath County, Texas. Late April.

135. More diversity in Cross Timbers- Yellow or Nuttall's stonecrop (Sedum nuttallianum) is another annual of the Crassulaceae (stonecrop family) that is well adapted to shallow, rocky soils of grassland and savanna vegetation. The specimen presented in these two nested "photoplots" was growing on a limestone outcrop on degraded tallgrass prairie on the Grand Prairie of northcentral Texas. Other plants of this species were found growing on an adjoining range in the West Cross Timbers. Diggs et al. (1999, ps. 564) described S. nuttallianum as growing on both sandstone-derived soils (as in Cross Timbers ) and limestone soils (as in Grand Prairie). The current author included this example in the chapter, Tallgrass Prairie-IB as well as here with West Cross Timbers under Tallgrass Prairie Savanna.

This dainty little succulent is as versatile and tough as it is eye-catching. Succulent, which is used as both noun and adjective, is a general (and thus somewhat vague) term describing the morphology (and associated anatomy and physiology) of plants having thick, heavy leaves and stems due to extra water-storing capacity. Fleshy is a related descriptive term and one often used synonymously with succulent, but the latter is more precise with regard to tissues modified to store greater amounts of water. Agave and cactus species are, of course, better known succulents (= succulent plants).

These latter mentioned succulents share with Sedum species (all members of the stonecrop family, Crassulaceae, for that matter) the unique modified pathway of photosynthesis named after this family: Crassulacean Acid Metabolism. From a physiological standpoint thisis the the most striking feature of Sedum and other members of the stonecrop family. This is not the juncture for a discourse on superior water-use efficiency, unique plant anatomy, natural selection, and the array of plant species having CAM photosynthesis. Standard textbooks on Plant Physiology, Plant Ecology, Plant Taxonomy, etc. offered appropriate treatment of this photosynthetic adaptation. The published symposium proceedings, Crassulacean Acid Metabolism, edited by Ting and Gibbs (1982) was also recommended.

Erath County, Texas. Mid-May; peak-bloom phenology.

Cross Timbers range produces various media for growth of reducers including fungi. Orgainc substances ranging from the wood of trees to various combinations of litter from hardwoods (shed leaves, fallen branches) and herbaceous species (fine to coarse shoots, roots) in combination with relatively rapid rates of detritis decomposition results in rich media for various fungi, both decomposers as well as free-living species. Some of the more common fungal species in the Cross Timbers were presented in the following section.

136. Glistening bodies- Fruiting bodies of glistening inkcap (Coprinus micaceus) growing on rotting roots of sugarberry (Celtis laevigata) in the West Cross Timbers. This is one of several Coprinus species found in the geographic region of Cross Timbers and adjoining prairies. Some of these were treated in Metzler and Metzler (1992, p. 193-198), a nice field reference for common Texas fungi.

This genus is in Agaricales, the order of gilled mushrooms which are in the Basidiomycota (previously the class, Basidiomycetes) and, more specifically, the Agaricomycotina which is a subphylum (= subdivision) including class Agaricomycetes which encompasses most of the fungi commonly known as" mushrooms".

Erath County, Texas. March.

137. Two bunches of friends- Two clumps of fruiting bodies (the last two photographs are general and more detailed views of one clump) of friendship or ringless honey mushroom (Armillaria tabescens= Armarillariella tabescens). The first group (slide one) was a day or two less mature than the more advanced and drying/rotting one presented in last two photographs. Both of these groups of fruiting bodies were growing on decaying roots of oak trees.

These gilled mushrooms are also in Agaricales like the preceding species. Readers were referred to the field guide of Texas mushrooms by Metzler and Metzler (1992, p. 138).

Erath County, Texas. First slide taken in early December; second and third slide, in mid November (of different years).

138. .Earthstars on the sandy earth- Two fruiting bodies of an earthstar (Scleroderma polyrhizon= S. polyrhizum) growing on sandy soil of the West Cross Timbers. This species is in family Sclerodermataceae (order, Scleromatales) of the Gast[e]romycetes, the subclass of fungi within class Basidiomycetes that produce their spores within their fruiting bodies and in which the hymenium remains enclosed until maturation of spores.

Erath County, Texas. Mid November.

139. Another of the same- One more fruiting body of S. polyrhizum in the West Cross Timbers of north central Texas. These two phographs presented a more detailed perspective of this species.

Erath County, Texas. Mid November.

140. Not an instrument, but...-Barometer earthstar (Astraeus hygrometricus) shown as top or dorsal view (first slide) and bottom or ventral view (second slide). This specimen was growing in a local transition zone between the West Cross Timbers and Fort Worth or Grand Prairie in north central Texas. This fruiting body was past its prime with the spore sac having already partially collapsed. The dark rays are the outer skin which splits into this pattern at maturity (Metzler and Metzler, 1992, p. 298). The rays flatten with increasing moisture (including that of humidity), but tend to close back up under drier air as seen here. This specific epithet, hygrometricus, indicates this hygroscopic-like feature.

Technically this species is a false earthstar. It is a mycorrhizal species with certain trees (Metzler and Metzler, 1992, p. 298) as, in this instance, Spanish oak or Texas red oak (Quercus buckleyi , previously Q. texana).

Hunewell Ranch, Erath County, Texas.

141. Conked on a post oak-Fruiting body (= sporocarp) of oak cushion brakcet, oak polypore, or oak conk (Polyporus gilveus= Fomes gilveus= Phellinus gilveus). A mature post oak served as host for an individual of oak conk over a span of 13 growing seasons in the West Cross Timbers of northcentral Texas. Three seperate fruiting bodies appeared over this time frame. These three sexual structure were shown in 1) this slide, 2) the next single slide, and 3) two slides thereafter, respectively. These three fruiting bodies grew within two feet of each other on the south side of the trunk of an ancient, slowly senescing post oak close to a spot of decay (rotten wood) near where the mature tree's lowest limb had been sawed off decades earlier. This species is most commonly found on dead wood (Riffle and Conway in Riffle and Peterson, 1986).

The number of years (if any) prior to this during which spore-bearing structures of this specific plant or organism (= genetic individual or genotype) appeared was not known to the author.

Erath County, Texas. March.

142. Conked again two years later-About 18 months after appearance of the fruiting body shown immediately the second conk, shelf, or bracket (sporocarp, the spore-bearing structure) of the same oak polypore or conk grew out of rotting wood (a site near removal of mature lower limb) of an ancient post oak in the West Cross Timbers. This particular conk appeared in early autumn whereas the preceding bracket or shelf (presented in the previous slide) grew out in late winter/early spring.

One of the more interesting things about Phellinus species is that they emit chloromethane, an important "greenhouse gas", (Harper and Kennedy, 1986; Harper et al., 2002). This has been most widely studied in P. pomaceus (Saxena et al., 1998; McNally and Haarper, 1991).

Erath County, Texas. October.

143. Conked ten years later-A decade (generally a dry to droughty period) elapsed before the oak polypore or conk plant (same genetic organism) produced another sporocarp, spore-bearing structure. Like the last sexual structure this fruiting body also appeared in autumn following a very dry early to mid summer and an extremely wet late summer to early autumn. Note the considerable variation in fruiting bodies of the same fungal organism (= same genotype) over the span of 13 years.

The second of these two photographs showed the many openings ("pores") through which spores were released. Hence, one--of several--genus name (Polyporus), family name (Polyporaceae), and, by estension, common name (polypore). Many species in the Polyporaceae have hymenium in vertical pores (ie. pores are aligned along depth of the sporocarp) on the underside of the fruiting bodies (conks, brackets, etc.). The hymenium is the tissue of the hymenophore of a fungal fruiting body or sporocarp where the sexual cells develop into basidia which in turn form the spores. The division encompassing the order Polyporales is the Basidiomycota. The basidiomycete fungi include gill mushrooms, puffballs, earthstars, stinkhorns, bracket fungi, jelly fungi, as well as such plant pathogens as the smuts, bunts, and rusts.

Erath County, Texas. October.

144. Ring of fungal fairies- Two views of a fairy ring fruiting bodies of a typical Texas Cross Timbers pasture toadstool, green-spored parasol mushroom (Cholorophyllum molybdites). Late summer showerrs, especially if heavy rainfall, results in almost overnight appearance of these organs. Spores from previous caprophores (fruiting bodies) are shed and drift on summer breezes in a radius (radial pattern).These pasture toadstools were growing in a West Cross Timbers yard of naturalized berrmudagrass (Cynodon dactyledon) and dallisgrass (Paspalum dilatatum). This species is in family Agaricaceae of the Baidiomycetes, Hymenomycetes taxonomic levels.

Erath County, Texas. Late August.

145. Supposedly green- Some caprophores (= fruiting bodies) of green-spored parasol toadstool. growing in the fairy ring shown in the two preceeding slides. Reducers or decomposers in a modified West Cross Timbers rang ecosystem.

Erath County, Texas. Late August after the blessing of a summer thundershower.

Post Oak Savanna in Wichita Mountains

In the Wichita Mountains of southwestern Oklahoma a climax woodland or savanna vegetation developed that was dominated by post oak and an herbaceous undetstorey of cool-season and warm-season grasses that are decreaser species of tallgrass, true, and mixed prairies. This climax range plant community could be visualized as an "island" of the Texas post oak savanna that developed roughly 200 to 300 miles to the east and south of the Wichita Mountains post oak-tallgrass savanna. The Wichita Mountains post oak-tallgrass savanna could also be conceptualized as an isolated western extension of the West Cross Timbers. While useful as a point of comparison (and departure) neither of these conceptual images is completely correct as vegetational origin or phylogeny.

It is perhaps the case that the Wichita Mountains provided a more mesic (or otherwise more favorable) habitat for both some plant species and their combinations into climax plant communities than existed in the general climatic region of this part of the western Central Lowlands physiographic province. The Wichita Mountains, which are part of the Arbuckle-Wichita uplift, comprise the Wichita Mountain district of the Central Lowland province (Fenneman, 1938, ps. 610, 617, 626-628). The Wichita Mountains are comparatively high because they were not base-leveled as was the case for the Arbuckle and Ouachita Mountains.

At any rate, one of the best remaining examples of the post oak-tallgrass savanna was to be found in the Wichita Mountains, and not in the once-extensive savanna of that name (and physiogonomy, structure, and composition) in the Texas vegetational or land resource area designated as Post Oak Savanna.

The following short section provided students with an example of what little vegetational relicts remain of the past and formerly vast post oak savanna. These photographs were taken on the Wichita Mountains National Wildlife Refuge in early August 2013. Slides were of a relict old-growth savanna that had been backfired in early September (about 2 September) 2011 as an emergency measure to save structures, including the refuge visitor and interpretative center, from a human-caused wildfire. The summer of 2011 in this area was the hottest on record since the year 1895. At this time a drought of the highest severity rating , Exceptional Drought (Palmer Drought Severity Scale), was in full force.

As shown in the following slides the emergency backfire induced damage to trunks and crowns of adult trees. The greatest impact, however, was topkilling (or total death) of some post oak seedlings and saplings. Damage to warm-season grasses was not as readily shown, but defoliation of decreaser tallgrass species at or near end of the warm-growing season can result in the greatest damage to such species because it occurrs when they are completing the annual growth and storing reserve nutrients for winter dormancy and spring green-up. In short, the wildfire and accompanied emergency backfiring could not have come at a sorse time for most species in the savanna vegetation.

144. Damage to old and young alike- Physiogonomy, structure, and composition of a savanna of ancient post oaks with an herbaceous understorey as it appeared two years following emergency backfiring (2 September, 2011) as a defense against a hot, summer wildfire. The herbaceous understorey consisted of two layers and ranged from a "solid stand" (single-species population) of Canada wildrye (Elymus canadensis) to an herbaceous layer of predominantly warm-season grasses (both eragrostoid and panicoid species) including silver bluestem (Andropogon saccharoides), plains lovegrass (Eragrostis intermedia), sideoats grama (Bouteloua curtipendula), hairy grama (B. hirsuta), and buffalograss (Buchloe dactyloides). This "hodge-podge" of warm-season grasses was in essence a mixed prairie. Conspicuous by its absence from this mixed prairie layer was little bluestem and, less conspicuously so, other tallgrass species especially Indiangrass.

Major forbs included western ragweed (Ambrosia psilostachya), annual broomweed (Gutierrezia draculoides), and curlycup gumweed (Grindellia squarrosa). The low-growing eastern pricklypear cactus (Opuntia compressa) was present, but this shrub was not of such cover as to comprise a lower woody layer.

There were seedlings and saplings of post oak that formed a lower, though very sporadic, woody layer. The emergency backfire had killed (at least topkilled) many of these small trees, but many had survived (mostly through resprouting following the backfire).

Fire damage to both trunks and crowns of ancient (old -growth specimens) post oaks was apparent in these two slides (including the fire-blackened left side of the trunk of the foremost tree in the second or lower slide).

This fire occurred during an Extraordinary Drought (Palmer Scale) and at a time of extremely hot temperatures.

Wichita Mountains National Wildlife Refuge, Comanche County, Oklahoma. Early August; estival aspect. FRES No. 15 (Oak-Hickory Forest & Woodland Ecosystem). K-72 (Oak Savanna). No SRM (this is not Cross Timbers). SAF 40 (Post Oak variant of Post Oak-Blackjack Oak). No biotic community unit in Brown et al. (1998). Central Great Plains- Wichita Mountains ecoregion 27k (Woods et al., 2005).

145. Damage, but survival- Exterior view or margin (first slide) and interior view or inside (second slide) of a post oak-mixed prairie savanna in the Wichita Mountains of southwest Oklahoma. These two views were taken two years after emergency backfiring (2 September, 2011) to reduce damage (and save structures, including the visitor and interpretative center) from a hot summer wildfire that raged during an Extraordinary Drought (including record high temperatures).

The old-growth post oaks showed fire damage, especially to their crowns, but these ancient trees were also naturally senescing (slowly dying of old age) as they apporach end of their life cycles. The small green "bushes" in foreground of both photographs were seedlings or small saplings (probably most were resprouts following the backfire) of post oak. There was obviously adequate regeneration of post oak to maintain this climax savanna range vegetation.

Grass species included silver bluestem, plains lovegrass, sideoats grama, hairy grama, buffalograss, and, deeper in the interior of the savanna (actually a woodland form of range vegetation), Canada wildrye. Canada wildrye was, in some more interior parts of the understorey, the sole herbaceous species such that this climax plant community was a post oak-Canada wildrye or Quercus stellata-Elymus canadensis habitat type by the Daubenmire (1968) classification scheme. Major forb species included western ragweed, annual broomweed, and curlycup gumweed. There were also some plants of eastern pricklypear cactus.

146. This understorey not much affected- In the interior of an old-growth post oak savanna in the Wichita Mountains of southwestrn Oklahoma Canada wildrye was commonly the sole herbaceous (if not the only plant) species in the understorey. In some places there were warm-season grasses (both eragrostoid and panicoid species), some forbs, and even seedlings or saplings of post oak with or without Canada wildrye. Overall, however, Canada wildrye was the dominant--often almost exclusive--member of the understorey that developed beneath these ancient post oak trees. This climax range vegetation certainly was a post oak-Canada wildrye or Quercus stellata-Elymus canadensis habitat type (Daubenmire, 1968).

This climax savanna vegetation was shown two years after an emergency backfire was used to save the visitor and interpretative center of this national wildlife refuge and, secondarily, to reduce unnatural damage to the savanna plant community from a human-caused, hot, summer (1 September, 2011) wildfire. The backfire burned when the Canada wildrye was dormant (prior to fall green-up and during warm-season dormancy) so that there was probably no damage to this cool-season member of the wheat or barley tribe (Tritaceae or Hordeae). It was possible that the backfire (which took place during Extraordinary Drought) gave a competitive advantage to this cool-season festucoid grass in contrast to any warm-season grasses or forbs that were attempting to grow and complete their annual growth cycle during late summer and drought (again, when, Canada or nodding wildrye was dormant).

147. The "lower level" on the outskirts- Two "nested photoplots" of an old-growth post oak-mixed prairie savanna in the Wichita Mountains of the western Central Lowlands physiographic province. This climax range plant community had been burnt by an emergency backfire (2 September, 2011) two years earlier during Extraordinary drought (Palmer Index). A human-set, hot, summer wildfire threatened a national wildlife interpretative and visitor center as well as this climax range vegetation (with a largely unnatural fire situation), but even the cooler backfire did damage to post oak (and presumedly to native, warm-season grasses and forbs).

Evidence of damage to crowns of the old-growth post oak was visible in the first slide which served as a "photographic transect" from the perimeter or margin of the savanna, that was adjacent to a mixed prairie of little bluestem and sideoats grama (co-dominants), into the interior of this post oak-mixed grass savanna. Students should note that there were resprouts of post oak in the far-foreground (right margin) of this "phototransect". Fire had not prevented regeneration of post oak.

Ths second slide ("sub-transect" or "nested photoplot") showed the sward of the herbaceous understorey of this post oak-mixed prairie savanna. Grass species in this savanna sward included silver bluestem, plains lovegrass, sideoats grama, hairy grama, and buffalograss. Eastern pricklypear cactus was also present but nowhere abundant in this savanna vegetation. This combination of mid-grass and shortgrass species amounted to a mixed prairie. It was for this reason that this climax range plant community was interpreted as a post oak-mixed prairie savanna. In the deep interior of the savanna Canada or nodding wildrye was the almost sole component of the herbceous layer (slide/caption unit immediately above), but on outer parts (eg. perimeter or margin ) of this savanna range it was a post oak-mixed prairie savanna. Important forb species were western ragweed, annual broomweed, and curlycup gumweed.

Prairie Peninsula

The largest ecotone or transition zone between eastern deciduous forest and tallgrass prairie was the climax vegetation termed the Prairie Peninsula by Transeau (1935). This tallgrass and true prairie-deciduous forest ecotone in pre-Columbian North America was one of the largest savannahs on the continent. The Prairie Peninsula can, and frequently has been, interpreted as including the Cross Timbers as it southern- and western-most extensions. At most general or loose interpretation, however, the Cross Timbers can be interpreted as vegetational "islands" of the "mainland" peninsula of this deciduous forest-grassland ecotone. In a stricter sense the Prairie Peninsula was traditionally limited to more humid or, at least, more mesic soil conditions. Kuchler (1964, 1966) followed this convention. Kuchler (1964) designated an obviously more restricted Prairie Peninsula as Oak Savanna (unit 81) as distinguished from Cedar Galdes (unit 83) and Cross Timbers (unit 84). In USDA Forest Service Forest and Range Ecosytems (Garrison et al., 1977) the Kuchler (1966) map of potential natural vegetation distinguished within the Grassland and Forest Combinations between mapping unit of 73, Mosaic of units 66 (Bluestem Prairie) and 91 (Oak-Hickory Forest), and mapping unit 75, Cross Timbers. This traditional treatment was followed herein so that the Prairie Peninsula was dealt with below. Cedar Glades (which are balds or barrens rather than the similar and, perhaps, closely related-- successionally, floristically, edaphically, climatically, etc.-- oak-hickory forest-tallgrass prairie savanna) were treated under Miscellaneous Grasslands.

Braun (1950, ps. 177-191), the ultimate authority of the eastern deciduous forest, interpreted the Forest-Prairie Transition as part of the Oak-Hickory Forest Region. She distinguished the Prairie Peninsula Section (Braun, 1950, ps. 185-191) as distinct from the Mississippi Valley Section and Cross Timbers. Shelford (1963, ps. 306-319) treated the Prairie Peninsula, without using this designation or citing Transeau (1935), within a larger ecological unit or biotic commuity he called "grassland-deciduous forest contact". Miscellaneous references to or brief descriptions of the Prairie Peninsula included (McPherson, 1997, ps. 34-37). Nelson (1987, ps. 59-74) recognized nine savanna natural communities in Missouri (including those ecotones in both the glaciated plains and the Ozark Plateau (Ozark Mountains): 1) dry savanna, 2), dry-mesic savanna, 3) mesic savanna, 4) wet-mesic savanna, 5) limestone/dolomite savanna, 6) chert savanna, 7) sandstone savanna, 8) sand savanna, and 9) igneous savanna. Most, if not all, of these could be interpreted as part of the greater Prairie Peninsula (including isolated ecotones within oak-hickory forests such as those of the Ozarks). All of these were lumped and described together generally (and simplistically) as Savanna, SRM 801, rangeland cover type by the Society for Range Management (Shiflet, 1994).

148. Oak-hickory-tallgrass savanna- The Ozark Plateau of Missouri, Arkansas, Oklahoma and southeast Kansas is the prominent transition between the western-most extension of oak-hickory forest and the Cherokee Prairie dominated by big bluestem and Indiangrass with such associated species as little bluestem, switchgrass, tall dropseed and leguminous and composite forbs. This example of the Ozark Highland province is a community of both red and white oaks such as post oak, blackjack oak (Quercus marylandica), black oak (Q. velutina), northern red oak (Q. rubra= Q. borealis), and both black or Texas hickory (Carya texana) and white or mockernut hickory (C. tomentosa= C. alba). There was an obvious shrub layer of dogwood (Cornus florida) and redbud (Cercis canadensis). Big bluestem is so dominant as the understory herb that local hillbillies demonstrate their ecological folk wisdom and know it as “timber grass”. Conspicuous forbs included Baldwin ironweed (Vernonia baldwinii), rosinweed (Silphium integrifolium); tickclovers (Desmodium spp.), along with trailing lespedeza (Lespedeza procumbens), roundhead lespedeza (L. capitatus), slender lespedeza (L. virginica), and serecia lespedeza (L. cunneata), this latter a naturalized agronomic (and, now, weedy) species.

Stoney Point Savanna in Ottawa County, Oklahoma. September; late estival to early autumnal aspect Ecotone between FRES No. 15 (Oak-Hickory Forest Ecosystem) and FRES No. 39 (Prairie Ecosystem). Clearly K-73 (Mosaic of Bluestem Prairie [K-66] and Oak-Hickory Forest [K-91]. SRM 801 (Savanna). Ozark Highlands- Ozark Plateau Ecoregion, 39a (Woods et al., 2005).

149. Winter range on an oak-hickory-tallgrass savanna- Winter vegetation of a relict savannah in western Ozark (Springfield) Plateau as an ecotone between tallgrass range community of Cherokee Prairie to the west and oak-hickory forest range to the east. These three progressively closer views are of the same savanna range introduced immediately above with closer location to the two farthest trees in background of above photograph. Those two trees were old-growth, open-crown form of northern red oak.

Except for presence of trees and local shrubs this range vegetation was tallgrass prairie dominated by big bluestem with Indiangrass as associate and with little bluestem, purpletop, and beaked panicgrass as other major grass species. Broomsedge bluestem, a native invader, and tall fescue (Festuca arundinacea), an introduced and frequently naturalized invader, were absent from this pristine sward. Species of native forbs, which also attested to the climax state of this savanna vegetation included tickclovers; roundhead, trailing, and slender lespedeza (all three being species of native Lespedeza); and rosinweed. Baldwin ironweed, an invasive though native composite, and the introduced-and-turned-weedy serecia lespedeza were the local "unwanted guest". These were not major components of this nearly virgin vegetation. Shrubs present in these three "nested photoplots" included blackberry (Rubus sp.), a few smooth sumac (Rhus glabra), and, as presented below, fox or frost grape (Vitis vulpina) in trees. Other shrubs such as eastern redbud and flowering dogwood that were present lower down on this hill (shown in above slide) were absent from the range plant community shown here. There was sexual reproduction of northern red oak with several seedlings growing less than height of the apparently parent trees shown here.

Various Quercus and Carya species that were present in photographs taken at greater spatial scale were not present in these scenes so they were not listed. These other tree species were listed under captions describing photographs that included representatives of those trees.

Stoney Point Savanna in Ottawa County, Oklahoma. September; late estival to early autumnal aspect. Ecotone between FRES No. 15 (Oak-Hickory Forest Ecosystem) and FRES No. 39 (Prairie Ecosystem). Clearly K-73 (Mosaic of Bluestem Prairie [K-66] and Oak-Hickory Forest [K-91]. SRM 801 (Savanna). Chert Savanna range site. Ozark Highlands- Ozark Plateau Ecoregion, 39a (Woods et al., 2005).

150. Northern red oak and friends on an Ozark savanna- A senescing northern red oak (one of the two shown in the preceding slides) with fox or frost grape as a sidekick grew on a rocky ridge of an Ozark Plateau savanna of prairie tallgrasses and trees of various oak and hickory species. These species were listed in some of the above captions and were not repeated here because northern red oak was the only tree species shown in photographs of winter vegetation. Other plant species present within radius of this tree's height included big bluestem, Indiangrass, little bluestem, purpletop, beaked panicgrass, slender lespedeza, trailing lespedeza, roundhead lespedeza, tickclover species, blackberry, rosinweed, and Baldwin ironweed among natives and serezia lespedeza, a naturalized agronomic forage.

151. Another red oak and some of the same friends on the same savanna- A second senescing northern red oak (and the second one introduced above) with a second fox or frost grape serving as an arboreal layer escort. Other range plants that grew within the distance equal to radius of this tree's height included Other plant species present within radius of this tree's height included big bluestem, Indiangrass, little bluestem, purpletop, and beaked panicgrass among the common native Gramineae. The Leguminosae was extremely well-represented by such natives as slender lespedeza, trailing lespedeza, roundhead lespedeza, and tickclovers as well as the naturalized introduced forage species, serecia lespedeza. Major native composites were rosinweed and Baldwin ironweed. Some species of dewberry (Rubus sp.) was twinning at the burled based of this old codger.

Cause of this burl was unknown, but the author strongly suspected that frequent fires in decades past was one factor. This tract of native pasture was frequently burnt 30 to 40 years prior to time of photographs (when the author attended the one-room school just across a county road and looked forward to spring fires).

152. Litter layer- Land surface layer beneath the first northern red oak (one without the burl) shown in detail above. Fallen across the carpet of bronze-colored leaves of this old, oaken, Ozark denizen were shoots of big bluestem, Indiangrass, and little bluestem. Students of range vegetation must bear in mind that the surface layer is part of the plant community, and destined to become part of the O horizon of the soil that supports it.

Personal perspective: What the author dubbed Stoney Point Savanna was just north (a hundred yards or so) of Stoney Point North No. 7 School, a rural district housed in a fine (and new) yellow brick building with one classroom inside, at which this photographer received the first eight years of his education.(Stoney Points was a mile and a half from this would-be author's house and walking when the road was rough and bike-riding when it was smooth constituted the "comute".) There was another savanna with similar vegetation (though in somewhat lower range condition) immediately behind the schoolhouse (close to the white, clapboard outhouses). Frequently, from autumn through winter to sometime in the spring students at Stoney Point fashioned "straw huts" out of the tall shoots pulled from the large clumps of prairie grasses growing among the oak and hickory trees on the ungrazed savanna (just beyond the schoolyard where students were supposed to play).

Students quickly learned that "timbergrass" (ie. big bluestem as this author discovered in later years) broke off easier and could be bent into shape and "stuffed in" better than the straw from what was known as broomsedge. After being reinforced with a higher education in Range Management and Animal Science years and miles from Stoney Point the school boy who was to assemble the work shown here understood that "timbergrass" was also more easily "stuffed in" and processed out of reticulorumens and that, in fact, grazing animals chose "timbergrass" while avoiding broomsedge-- just Stoney Point school boys.

Many a scheme was concocted, many a boyhood dream dreamt, many a plot plotted, and many the incidents cogitated on within those "straw huts" of "timbergrass". Decades later and "schools where college students go" afterward, the lessons learned in the brick schoolhouse and on an "extramural" playground with prairie grass playhouses atop a rocky hill have remained. In retrospection from the backside of a career in higher education, this Stoney Point school boy can only conclude that the demise of the one-room school and its replacement with factory schools, bus routes, "organized sports", and computers was a profound and an irreplacable loss, an expensive though cheapened and lessened education. Not exactly this educator's concept of progress. Maybe someday somehow some of the benefits of that small, rural education will be rediscovered like the savanna across the road from Stoney Point school. Afterall, the "timbergrass" still grows tall on the rocky Ozark soil.

153. A story in the woods- Pop quiz time: what happened to this parcel of Ozark Plateau vegetation? During the last half of the Twentieth Century ecologists studied oak-hickory forests in Missouri and compared species composition and structure of the forests existing then to that of pre-settlement vegetation based on precise, detailed accounts made by land surveyors and observations by early travelers (Steyermark, 1940; Beilmann and Benner, 1951; Howell and Kucera, 1956; Steyermark, 1959). Their studies revealed an astonishing increase in trees and understory shrubs to the extent that the pre-European Ozark Plateau savanna vegetation of oak-hickory and tallgrass prairie species had been converted into a dense oak-hickory forest. This was due to such activities of white man as cultivation, overgrazing, overburning following by fire suppression, and transportation and related commercial traffic. Savannas through which pioneers drove wagons grew so dense with trees and woody underbrush as to become impassable other than by foot. This is literally a “textbook example” of afforestation used in undergraduate texts (eg. Carter, 1968, p. 397-398; Krebs, 1972, p.106).

This increase (invasion in the Clementsian model of plant succession) of woody species in the oak-hickory-tallgrass savanna is seen in this oak-hickory forest scene from the Ozark Mountains of southwest Missouri. The large tree is a mature black oak (Quercus velutina) which undeniably grew without neighbors as proven by its telltale horizonal limbs that could only develop when it is not crowded by other trees. The young trees, which are pignut hickories and mostly black oak progeny of the parent oak, by contrast have the straight, limb-less boles that can only develop in dense shade where competition for lightither prunes lower limbs or, as in this case, prevents their formation to begin with.

There is not an herbaceous layer in the understory, but a thick, mulch-like mat of oak and hickory leaves beneath layers of all-age oak and hickory. Likewise, flowering dogwood and redbud are so rare that the typical shrub layer is all but non-existant.

This is not an ecologically "healthy" plant community. It is not forest, and if it was it would be a dysfunctional one. This is a native savanna that lost its natural understory of tallgrass species (big bluestem or "timber grass" is the dominant decreaser) due to overgrazing by cattle, horses, and hogs coincident with relatively recent exclusion of fire which simultaneously killed out most of the prairie grasses while allowing an unnatural increase in tree density which resulted in complete canopy cover in turn preventing regeneration and development of the characteristic shrub and herb layers. Compare this vegetation to that of Stoney Point Savanna above. They are both Ozark Highlands Chert Savanna range site.

If the pre-white man Ozark Plateau vegetation was maintained as subclimax by Indians who set fires more frequently than the natural fire regime then designations of "fire type"or "fire disclimax" or, more generally, "anthropogenic climax or disclimax"would be appropriate. One could then argue that Indians were wildlifers instead of foresters and that they should have eaten squirrels instead of venison (or gone vegetarian), worshipped Smokey Bear, and dressed in Forest Service green.

The Ozark Mountains get plenty of "dry lightening" and best estimates are that an open oak-hickory-bluestem woodland similar to parklike conifer forest is the potential natural vegetation for some sites in the Ozark forest complex. The woody invasion in this photograph is not climax, the potential native vegetation; it is an example of range deterioration and improper vegetation management.

Proper management of forests, savannas, and bald knobs in the Ozark Highlands must include fire, and fire of intensity and frequency sufficient to reduce tree density and allow understory development. Buffalo Hills Natural Area, McDonald County, Missouri. Estival aspect. June. FRES No. 15 (Oak-Hickory Forest Ecosystem), K-72 (Oak Savanna, technically Oak-Hickory Savanna), Classified as chert savanna by Missouri Natural Areas Committee (Nelson,1987). SRM 801 (Savanna).Ozark Highlands- Ozark Plateau Ecoregion, 39a (Chapman et al., 2002).

154. Burnt-over oak-hickory-tallgrass savanna (limestone/dolomite savanna)- It was explained following the pop quiz with the preceding slide that much, probably most, of the vegetation of the Ozark Mountain Region experienced afforestation, formation of forests where forests had previously been absent under the existing climate. This phenomenon was probably best documented for the Ozarks in what is the present state of Missouri. Sources on which comparisons of present vegetation to pre-white man vegetation can be based range from personal accounts and journals of travelers to surveyor's notes. The former were subjective and thus subject to misinterpretation by ecologists reading them two centuries later, but some were precise and written by the leading men of science of the day or at least by astute observers. The much-read journal of Missouri-Arkansas traveler, Schoolcraft (1821) is the best-known example of these. The meticulous notes of land surveyors— an unsung group of frontiersmen —have been analyzed and clearly served as a sound basis that showed extent of oak-hickory forest invasion into the oak-hickory-tallgrass savannas and tallgrass prairies of Missouri, especially the Ozarks. This increase in woody plants converted these savanna biomes into deciduous forests, or "brush patches". Anyone doubtintg such woody invasion and afforestation of much of the Show-Me State, in particular it's ancient Ozarks, should read— with a mind more open than the vegetation of the Ozarks— the analyses of such students of vegetation as Steryermark (1940, 1959), Beilmann and Brenner (1951), Howell and Kucera (1956), Kimmel and Probasco (1980), Schroeder (1982), and Natural Resources Conservation Service (1996, p. 41). A good introduction to the pre-Columbian (pre-settlement) vegetation of Missouri was presented by Thom and Wilson (1980). Schroeder (1982, p. 13) quoted the native Missouri Ozarker and dean of American soil taxonomists, Curtis Fletcher Marbut, as writing that the Ozarks were:

"… up to the middle of the 19^th century a region of open woods, large areas being almost treeless.
Except in roughtest land… the timber growth was not dense enough to hinder in any way the growth
of grass. The whole region in its vegetation was more closely allied to the western prairies than to the
timber-covered Appalachians".

The role and wisdom of the Indians in wise and skillful use of fire to maintain open forests, savannas, and prairies was mentioned with the preceding slide. It should be underscored that the earliest Caucasians in the Ozarks and adjoining prairies and savannas learned their lessons well from the American Indians and habitually fired the native Ozark vegetation. Fire was successively less employed as a tool in the progression (not necessarily progress) of groups of white man occupying the native land with their ever-increasing technological advancement. The first whites to enter the so-called wilderness were frontiersmen who set about converting the wilderness into the frontier, the transition between wilderness and thoroughly settled land (ie. "civilization"). From the eastern deciduous forest of eastern Canada to east Texas the first wave of frontiersmen were basically "a cross" between hunter-gathers and nomadic herdsmen (ie. "white Indians"). This first group of frontiersmen were historically designated the "American backwoodsman". The backswoodsmen were the first group or social class of Europeans to start the process of technological civilization (Lippencott, 1933, ps. 182-183; Moore, 1957, ps. 57-58, 69, 71-76, 80, 93, 95). They were as unique and distinctive as the occupationally related fur trappers, expecially the immortal "mountain men". The definitive work on the backswoodsmen— which have today been almost lost as a footnote in the pages of American history— and their ecological impact on the North American deciduous forest is the flawless study of Jordan and Kaups (1989). It is absolutely required reading for any who, like your author, would proudly proclaim: "Thank God I'm a hillbilly!" Sadly the bonafide hillbilly has about passed into the oblivion of his predecessor (and superior), the backwoodsmen. For all of their adverse effects on the eastern deciduous forests (eg. running free-ranging, unmanaged, "hog-wild", feral swine in the woods; ovcerlogging, overtrapping and overhunting wildlife) backswoodsmen at least knew one thing that "civilized citizens" forgot: you need to burn the woods.

At some point shortly after World War II far-sighted professionals educated in ecological principles (first, rangemen and wildlifers and, finally, foresters,) relearned the lessons of the Indians and the backswoodsmen, and prototype experiments with prescribed burning began. The history of fire practice on American ranges and forests was told in detail by Pyne (1982, 1984). Eventually Smokey Bear died (Hip, hip, hurray!) and even the fire-suppressing Forest Service "saw the light" (but only after more heat than light was generated) and began to practice— admittedly on a limited scale— the science and art of prescribed fire.

One example of that policy shift toward "pro-active" prescribed burning was captured on Kodachrome and included for readers' viewing pleasure in the above slide. This vegetation was of a black oak-dominated upland oak-hickory Ozark forest that had developed following decades of "protection from fire". This involved joint action of such diverse groups as the Missouri legislature which passed anti-burning measures as early as 1824 (Schroeder, 1982, p. 21 [citing several authors]), settlers (mostly farmers) fearful of property damage from wild fire, many activists in the early days of the Conservation Movements, including of course the U.S. Forest Service and allied conservation agencies (eg. Missouri Department of Conservation), and even youth organizations like the Boy Scouts of America and 4H Club. When "scientific truth" was better refined and the ecological role of fire became widespread knowledge (it did not exactly spread like wild fire) the same groups came to appreciate the benefical use of fire and responded appropriately, even if belatedly.

One such example of this conversion (not yet fire in the bellies of all former fire-purging sinners) was prescribed firing of this former oak-hickory- tallgrass savanna that turned closed-canopy forest under fire exclusion (a de facto type conversion) for the purpose of savanna restoration. Viewers can readily see that it has a way to go to get back to the vegetation described by Schoolcraft (1821) and land surveyors but it was a start. Actually the flames seemed to have sparked resolve in the oak and hickory species ,which were clearly invigorated, such that browsing wildlife (mostly whitetail deer) and other seral-disturbance species (eg. bobwhite quail) were the immediate beneficiaries of this range improvement project.

In the view of the fired savanna-turned-forest shown in this slide the most immediate vegetational change was reduced canopy of the oak-hickory crown layer and "explosions" in populations of sassafras (Sassafras albidum), smooth sumac (Rhus glabra), buckbrush, persimmon (Diospyros virginiana), blackberry (Rubus spp.), pokeweed (Phytolacca americana), giant ragweed (Ambrosia trifida), and other old-field species. There was some release of such climax decreasers as big bluestem, little bluestem, and Indiagrasss as well as increasers like purpletop and invaders like broomsedge bluestem.

Vegetation of the understory layers varied over small spatial scale existing as a patchwork of "mini"- (micro-) communities within the overall or general savanna-forest community that was subjected to the same fire treatment. A distinctively different understory community was presented in the next two succeeding photographs of this same management area, the same savanna (or forest if one chooses).

Details of prescribed fire history on this management area including fire management plan, fire regimen, and firing technique were unknown to author (and, in fact, apparently rather "smokey" to the Forest Service tour guide).

North aspect but mid-slope (compare to hilltop of north slope in next slide).

FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Oak Savanna). SRM 801 (Savanna). SAF— this is the interesting part —65 (Sassafras-Persimmon) which had been converted from the former SAF 110 (Black Oak). Ozark Highlands- White River Hills Ecoregion, 39c (Chapman et al., 2002). Limestone/dolomite Savanna. Mark Twain National Forest, Ava Ranger District, Buttram Hollow Allotment, Ozark County, Missouri. July.

155. Oak-hickory-tallgrass savanna (limestone/dolomite savanna) treated by prescribed burning- This was a slightly different view of the same general plant community presented in the prior slide. It was the same management area— the same small portion of "woods" burnt with the same fires. (The same clearing on the far hilltop can be seen or, as was often the case, at least it could be seen in the original slide prior to treatment as a j-peg and presentation in the compact disk.). It was specified in the preceding slide that the vegetation of the understory layers varied in a mosaic pattern over a relatively small surface area. In the part of the understory vegetation shown here prescribed fire resulted in a different plant community at local scale. Instead of releasing mostly seral woody species—namely sassafras, persimmon, buckbrush, and sumac—as in the local or micro-community shown above, here the same set of fire treatments released climax tallgrass species as well. Big bluestem and Indiangrass were the dominant grasses and the composite, black-eyed susan (Rudbeckia hirta), was the dominant forb present following prescription firing of this Ozark savanna. The major increaser was purpletop (Tridens flavus). There was also great abundance of the same woody species listed under the preceding photograph (primarily sassafras, persimmon, and smooth sumac), but dominance shifted among species and growth or life form. Phanerophytes were released to point of dominance in the local understory vegetation seen immediately above whereas in the "patch" of understory shown here the hemicryptophytes and cryptophytes (= geophytes) dominated the post-prescribed burn vegetation.

Dominant tree species were presented in the succeeding slide which was the third vantage point shown of this savanna-turned-forest-being-turned back-to-savanna vegetation.

This photo-point was more of the crest of a north slope aspect than that of the mid-slope seen in the preceding slide. This could could explain some of the difference in vegetation.

FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Oak Savanna). SRM 801 (Savanna). SAF designation probably of limited value (if not meaningless), but SAF 65 (Sassafras-Persimmon) converted from a cross between SAF 110 (Black Oak) X SAF 40 (Post Oak-Blackjack Oak). Limestone/dolomite savanna. Ozark Highlands- White River Hills Ecoregion, 39c (Chapman et al., 2002).

Mark Twain National Forest, Ava Ranger District, Buttram Hollow Allotment, Ozark County, Missouri. July.

156. Post oak-black oak-tallgrass savanna (limestone/dolomite savanna) maintained by prescription burning- This was the third focal or vantage point of a Ozark Mountain oak-hickory-tallgrass savanna that had developed such a dense woody component to the understory that the herbaceous layer(s) had become (or were becoming) lost. The savanna community was being replaced by forest; savanna was being or had been converted into forest. This was due to fire exclusion: "fire protection" (ie. suppression of the natural fire regime, whatever that might have been, was most certainly protection of the forest against fire). The "rub" was that the climax or potential natural vegetation for this site was not forest but savanna. The same species of trees— mostly black, post, blackjack oaks with limited northern red and white oaks and some hickory species —were common to both forms of plant community. The difference was in community form (physiogonomy, architecture, structure, tree density, and crown cover) and development of an herbaceous layer in the understory.

Fire suppression caused a type conversion. In fact, this was technically a biome conversion: ahardwood-tallgrass savanna— the ecotone between tallgrass prairie and oak-hickory deciduous forest— was converted (or was being converted) into a forest of anthropogenic origin (ie. it now was or was becoming a man-made forest; human action caused afforestation).

This change in vegetation constituted ecosystem deterioration. From the perspective of Range Management this was range depletion. The range ecosystem was changed drastically based on departure of the plant community (along with native animals, the ecosystem consumers) from potential natural vegetation.

The dominant tree in this particular parcel of vegetation was post oak, but black and blackjack oaks were also present as associates. The prominent grass in center foreground was Indiangrasss. Big bluestem (known among local hillsmen as "timber grass") was also common, but Indiangrass is a long shoot grass species and at mid-point in the growing seaon it was much taller and appeared generally larger than big bluestem which is a short shoot grass. (Beginning students in Range Management should master the concept of long shoot vs. short shoot. These classic references were highly recommended: Branson [1953], Rechenthin [1956], Younger and McKell [1972], Sosebee [1977, ps. 258-272]). Canada and Virginia wildrye were present as associate grasss species. Purpletop was the predominant increaser grass. Woody species common in the understorey included smooth sumac, buckbrush, and blackberry among shrubs. Tree regeneration was relatively high with seedlings and saplings of all the oak species (especially post oak) widespread (ie. prescribed fire did not prevent tree recruitment).

FRES No. 15 (Oak-Hickory Woodland Ecosystem), K- 72 (Oak Savanna). SRM 801 (Savanna). SAF is theoretically meaningless because this is an oak-hiockory-tallgrass savanna not a forest (thus technically not a forest cover type), but SAF 40 came closest on basis of dominant species. Limestone/dolomite Savanna. Ozark Highlands- White River Hills Ecoregion, 39c (Chapman et al., 2002). Mark Twain National Forest, Ava Ranger District, Buttram Hollow Allotment, Ozark County, Missouri. July.

157. Ozark oak-hickory-tallgrass savanna (limestone/dolomite savanna) under fire exclusion- This was the "control plot" portion of the oak-hickory-tallgrasss savanna shown in the last three photographs. Complete "fire protection" of this check plot allowed conversion of a savanna community to a forest community. This was Smokey Bear's woods whereas the last three slides were of a rangeman's woods. This unburned part of the management area shown here was just across a Forest Service earthern road from the savanna subjected to prescribed burning shown in the three preceding slides. Tree regeneration (predominately post oak with black and blackjack oaks as associate species) was very high with all age classes of seedlings and saplings represented up to the near old-growth stage (tree on far left margin that was developing horizonal limbs). Compare the thick mulch of oak leaves, which in combination with closed canopy prevented any development of an herbaceous understorey, with the mosaic pattern of bare ground and understory layers of tallgrass and shrub species visible in the preceding slide.

FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Oak Savanna). SRM 801 (Savanna) is potential natural vegetation but here fire exclusion led to conversion of an oak savanna to a post oak-dominated forest cover type so no longer SRM 801 but SAF 40 (Post Oak-Blackjack Oak). This was example of afforestation and retrogression (disturbation-induced retrograde movement down a sere) with deterioration of native vegetation due to underburning (ie. an anthropogenic plant community). Limestone/dolomite Savanna. Ozark Highlands- White River Hills Ecoregion, 39c (Chapman et al., 2002). Mark Twain National Forest, Ava Ranger District, Buttram Hollow Allotment, Ozark County, Missouri. July.

158. Sampler of the Prairie Peninsula- Much of the potential natural (climax) range vegetation in the western Ozark Highlands and eastern Cherokee Prairie (of the Central Lowlands physiographic province) is a patchwork of oak-hickory forest, tallgrass prairie, and various combinations of these two major or general forest and rangeland cover types that form open woodlands and savannahs all of which together comprise the southwestern extension of the Prairie Peninsula (Transeau, 1935, Fig. 1). Range vegetation presented in these two photographs was an example of the species composition, structure, and spatial arrangement of the Prairie Peninsula at local contact between two distinctive natural plant communities: 1) tallgrass prairie dominated by big bluestem (foreground of both slides) and 2) post oak-blackjack oak-Texas or Ozark hickory forest (background of both photographs).

This oak-hickory forest (second-growth forest having climax species composition and structure) was invading the tallgrass prairie in absence of fire and perhaps other disturbances such as extreme drought which had not affected this area in the last half century. Seedlings and small saplings of the three dominant and defining hardwood tree species were conspicuous in the immediate and narrow contact zone between forest and grassland. Other tree species in the forest included black oak, black cherry, American elm, and occasional eastern red cedar. Presence of the latter, the only conifer indigenous to this general area, was indicative of fire cessation and suppression. Shrubs in the oak-hickory forest included blackberry, smooth and winged sumac, eastern redbud and flowering dogwood with latter two being much less common in this forest tract. Other important herbaceous species--in both understorey of forest and tallgrass prairie included various grasses including silky and Canada or nodding wildryes (Elymus villosus, E. canadansis, respectively), purpletop (Tridens flavus), beaked panicgrass (Panicum anceps), broomsedge bluestem (Andropogon virginicus), and naturalized tall fescue (Festuca arundinacea); legumes (notably ticktrefoils [Desmodium spp]); and such composites as woodland or stiff-haired sunflower (Helianthus hirsutus), the dominant forb, pale purple coneflower (Echinacea pallida), needleleaf goldenrod (Solidago gymnospermoides), tall goldenrod (S. altissima), and the annual daisy fleabane (Erigeron strigosus).

Newton County, Missouri. June, vernal aspect. Prairie Peninsula. Potential natural (= climax) vegetation was an ecotone of oak-hickory forest and tallgrass prairie: FRES No.15 Oak-Hickory Woodland Ecosystem; K-73 (Mosaid of Bluestem Prairie (K-66) and Oak-Hickory Forest (K-91) (Garrison, 1977). Combination of SAF 40 (Post Oak-Blackjack Oak) in Eyre (1980) and SRM 803 (limestone or chert variant of Missouri Prairie) in Shiflet (1994). Patchwork of Oak-Hickory Series, 122.11, and Bluestem-Tall-Grass Series, 142.11 ((Brown et al., 1998. ps. 37 and 40, respectively). Ozark Highlands- Ozark Plateau Ecoregion, 39a (Chapman et al., 2002).

159. Hardwood invasion in the Prairie Peninsula- Gradual invasion of a local big bluestem-dominated tallgrass prairie by post and blackjack oaks and Texas or Ozark hickory from an adjoining oak-hickory forest of which these were the three dominant species. The seedlings and small saplings of these oak and hickory species were invading the prairie incrementally from the contact of the two range plant communities rather than throughout the grassland.

This photographer grew up in this locality and can distinctly remember when 50 years prior to the time of these photographs "burning off" of the woods was a spring ritual. To this author's pleasant memories as a boy blackberry picker these fires did not kill off blackberries (and certainly not the fire-l;oving sumacs), but there was considerably less dense cover of oak and hickory at that time when annual spring fires and hay-baling on the larger parcels of bluestem-Indiangrass prairie were taken for granted as standard practices in Ozark agriculture.

160. Details of oak-hickory invasion of bluestem prairie- In the Prairie Peninsula of the western Ozark Plateau post oak, blackjack oak, Ozark hickory and lesser cover of black oak and black cherry were invading a big bluestem-dominated prairie (beaked panicum, purpletop, Indiangrass were lesser species). Invasion was progressing from the forest-grassland edge with relatively little hardwood invasion in more interior parts of the tallgrass prairie. Encroachment of oak-hickory forest into other prairies that were conterminous with existing forest was by no means limited to this pattern of invasion from the perimeter. Nearby prairies were being lost to expansion of oak-hickory forest in which invasion was nearly uniform throughout prairies or even with invasion appearing to be more dense and rapid in more interior parts of bluestem grasslands.

Exact cuses(s) of forest encroachment was (were) not known, but folk wisdom, common sense, and personal observations by this authro implicate recent absence of fire. Many prairies were being invaded by hardwood tree species and eastern red cedar (juniper) that had not been grazed by ungulates other than white-teiled deer for a number of years. Livestock most certainly do not graze oaks and hickories in preference to grasses and they do not graze juniper at all.

The short sequence of five slides presented immediately below showed results of an early spring wildfire of moderate intensity that burned over a big bluestem-dominated prairie glade and through an adjoining upland, chert forest dominated by black oak (bitternut hickory [Carya cordiformis] was the major associate species) in the Springfield Plateau section of the Ozark Highlands. Other tree species included post oak, chinquapin (chinkapin) oak (Quercus muhlenbergii), American elm (Ulmus americana), and black cherry (Prunus serotina). This surface wildfire burnt in late March or early April when all hardwood and warm-season grasses and forbs were in dormancy. Over course of approximately the last four decades (less than a half century) there had been nor fires, logging, or livestock on this tract of oak-hickory forest and tallgrass prairie that is part of the southern portion of the Prairie Peninsula. In absence of fires or other disturbances (other than occasional ice storms) the upland black oak forest had invaded the big bluestem-dominated chert glade advancing from the forest perimeter outward so that the tallgrass prairie on the glade was becoming an oak-hickory forest. (Plant species were given below for each photograph.)

Effects from the wildfire (cause unknown) on ectonal range vegetation (that at edge of forest and grassland) were presented in the following five-slide sequence.Photographs were taken in late May and early June (approximately eight to ten weeks following the spring wildfire). Effects on the range vegetation in the interior of the black oak-bitternut hickory forest were presented in the chapter, Oak-Hickory Forest-II, in the Forests and Woodlands section of Range Types of North America. Both the big bluestem-dominated tallgrass prairie on the chert glade and the black oak-bitternut hickory upland forest were interpreted as climax (potential natural) range plant communities on this land from the perspective of polyclimax or climax pattern theory with topography and soils being determinative (ie. topographic and/or edphic climaxes) . From the monoclimax theory the tallgrass (big bluestem-dominated) prairie glade was preclimax to the regional climax of black oak-dominated and defined forest.

A mesic sugar maple-bitternut hickory forest on the north slope of a limestone bluff (above a creek) was conterminous with the upland black oak-bitternut hickory forest. In monoclimax theory this sugar maple-dominated forest that included white ash (Fraxinus americana), American elm, and basswood (Tilia americana) with an understorey of pawpaw (Asimina triloba), American bladdernut (Staphylea trifolia), and Jack-in-the pulpit (Arisaema triphyllum) and green dragon (A. dracontium) was postclimax to the regional, zonal, or climatic climax of black oak forest. Conterminous to the glade was go-back land that had been big bluestem-Indiangrass-prairie dropseed (Sporobolus heterolepis) tallgrass prairie prior to cultivation. On this prairie-turned farmland-abandoned-and-now-old field there was a large buffalo wallow that was less than a quarter mile from the sugar maple forested bluffs and the tallgrass prairie glade. This amazing mosaic of natural range vegetation that developed on a ptachwork of soils had almost unquestionably been maintained by some mixture of recurrent fires ignited by dry lightening or Indians, drought, buffalo grazing, wind and ice storms, a recipe of disturbances that will remain known only to God.

The role of fire in maintenance of the Prairie Peninsula and the associated savannah or woodland portions of range vegetation in the Oaark Plateau was presented for viewers education, and for the enjoyment of real rangemen who love to burn and delignt in the aftermath.

161. Trees meet grass, but it ain't romance- Range vegetation at edge of a big bluestem-dominated chert glade and an upland, dry-mesic, chert forest dominated by black oak as it appeared approximatedly eight to ten weeks following a wildfire that generated sufficient heat and height of flames to topkill black oaks that were roughly 40 foot tall with eight to ten inch diameters (DBH). There were fewer and smaller trees of post and chinkapin (chinquapin) oaks, American elm, and black cherry. The herbaceous vegetation in foreground was dominated by big bluestem with three-flower melic (Melica nitens)the assoicate speceis. Other herbs included the tallgrass species of Indiangrass, broomsedge bluestem (Andropogon virginicus), purpletop, and prairie dropseed along with such forbs as woodland sunflower (Helianthus hirsutus), Indian physic or American ipecac (Gillenia stipulata), goldern alexander (Ziza aurea), passion flower (Passiflora incarnata), and carrion flower (Smilax herbacea). Shrubs on the glade included blackberry (Rubus spp.), smooth suma, skunkbush sumac, coral berry or buckbrush, and summer grape (Vitis aestivalis). Seedlings and small saplings (up to slightly less than a yard tall) of post, black ,and chinquapin oaks (in that order of relative cover and density) had invaded the tallgrass prairie glade.

Range vegetation alone the perimeter black oak-bitternut hickory forest (vs. interior which was climax oak-hickory forest with multiple vegetational layers) included some individuals of the same species as on the glade plus pokeweed (Phytolaca americana), pointed-leaf or cluster-leaf ticktrefoil or, also, tick trefoil, or tick clover (Desmodium glutinosum), bigbract or large-bracted tick trefoil (D. cuspidatum) white vervain (Verbena urticifolia), and small skullcap (Scutellaria parvula) along with flowering dogwood, eastern redbud, shadbush or eastern serviceberry (Amerlanchier arborea), chinquapin oak, and black cherry. Also present--and as a key indicator indicator plant species--was eastern red cedar (Juniperus virginiana) along the forest-grassland edge and also occurring just on the outer zone of the forest interior.

The fire had topkilled essentiall all individuals of hardwood species on the glade, including blackberry, sumac, grape, and buckbrush. Most of these had resprouted so that several, years of aboveground biomass was removed (killed), but in process of being replaced quickly. In other words, periodic fires would be necessary for maintenance of glade vegetation.

Ottawa County, Oklahoma. June, late vernal aspect. Prairie Peninsula. Potential natural (= climax) vegetation was an ecotone of oak-hickory forest and tallgrass prairie: FRES No.15 Oak-Hickory Woodland Ecosystem; K-73 (Mosaid of Bluestem Prairie (K-66) and Oak-Hickory Forest (K-91) (Garrison, 1977). Combination of SAF 110 (Black Oak) in Eyre (1980) and SRM 803 (limestone or chert variant of Missouri Prairie) in Shiflet (1994). Patchwork of Oak-Hickory Series, 122.11, and Bluestem-Tall-Grass Series, 142.11 ((Brown et al., 1998. ps. 37 and 40, respectively). Ozark Highlands- Ozark Plateau Ecoregion, 39a (Woods et al., 2005).

162. Looking down the edge- A "pyric" fence-line contrast of black oak-bitternut hickory forest (left) and big bluestem-tallgrass prairie glade (right) about eight to ten weeks after an early spring (late March or early April) wildfire of moderate intensity burnt this range vegetation (for the first time in over 40 years). This was a natural ecotone between two climax range types in a mosaic of Ozark Plateau potential natural vegetation consisting of oak-hickory forests, tallgrass paririe grasslands and glades, and savannahs and woodlands due to intermixing of the first two range plant communities.

Plant species were listed in the immediately preceding caption. Most of the taller trees on the edge of the upland, dry-mesic, chert oak-hickory forest were black oak (there were fewer and smaller trees of post and chinquapin oaks, American elm, and black cherry). Herbaceous species in understorey of the forest edge included many of those on the chert glade including the dominant species, big bluestem, along with blackberry, smooth sumac, skunkbush sumac, and buckbrush. The major forb at grassland-forest edge was Indian physic or American ipecac. The associate forb was woodland sunflower. There was also some of the pioneering wild or blue lettuce (Lactuca canadensis).

Details of this forest-grassland (glade) edge were presented and described in the two slides that immediately followed this caption.

163. Prospering after fire (or happy grass on a glade)- Edge of a chert glade that adjoined an upland, dry-mesic black oak-dominated forest supported a rapidly growing fire-released, herbaceous range vegetationl of big bluestem, the dominant species, along with three-flowered melic, broomsedge bluestem, purpletop, Indian physic or American ipecac, the disturbance-colonized wild lettuce, carrion flower and passion flower. Woody species that had been topkilled, but that nonetheless and nothing-daunted had resprouted, included buckbrush, blackberry, smooth sumac, skunkbush sumac, summer grape, and post oak.

This forest and glade had not burned for over 40 years and woody plants had become established on the tallgrass prairie of the chert glade. This was a textbook case of the on-going, ecological, life-or-death "tug-of-war" characteristic between woody and herbaceous range vegetation in the grassland, forest, woodland, and savanna patchwork of natural range plant communities of the Prairie Peninsula (Transeau, 1935).

164. The invading forest drivern back by flames- The advancing front of a black oak-dominated upland, chert, dry-mesic forest that was invading a big bluestem-dominated tallgrass prairie range in the Springfield Plateau of the Ozark Highlands. With the heavy fuel provided by four to eight-foot shoots of big bluestem, three-flowered melic grass (along with some Indiangrass, broomsedge bluestem, and purpletop) plus finner fuels of woody plants like smooth and skunkbush sumacs, blackberry, and summer grape, the trunks of forty foot (eight to ten inch DBH) black oaks were topkilled. Hurray! Pyric brush control.

Herbaceous species shown in this "photo-plot" included Indian physic or American ipecac (to right of charred logs and blackened trunk of black oak), woodland sunflower, big bluestem, passion flower, along with annual colonizing species including wild lettuce, common ragweed, and giant ragweed.Resprouting woody species included smooth sumac, buckbrush, blackberry, and, of course and very conspicuously, black oak.

165. A forester's dread and a rangeman's delight- Three poles of black oak at edge of an upland, dry-mesic black oak-dominated forest and a big bluestem-dominated tallgrass prairie on a chert glade were topkilled by an early spring wildfire of moderate intensity and flame height. The largest oak (about nine inches DBH) and the second largest (trunk on the right) had not stump-sprouted like the smallest black oak (middle trunk) did. This was only eight to ten weeks post-burn and perhaps too soon for suckering (production of long shoots) from basal shoots. Even if the larger black oaks do eventually resprout from stump, shoot,or rootcrown there was many years' worth of accumulated, aboveground biomass destroyed. There were resprouts of blackberry, smooth and skunkbush sumac, and buckbrush. This land had not burned in over 40 years.

Herbaceous range species like big bluestem, three-flowered melic grass, and purpletop along with perennial forbs such as Indian physic or American ipecac, carrion flower, passion flower, and woodland sunflower plus annual colonizers (eg. common ragweed, wild lettuce, giant ragweed) had immediate benefit from reduced shade, competition for soil water, and other enhanced habitat variables. Rangemen rejoice for such gifts the same as for those of precipitation.

Ottawa County, Oklahoma. June, late vernal aspect.

166. Scene of wreckage , and recovery- In (or about) last week of May a motor cycle crashed and burnt up completely (with driver miraculously escaping with minor abrasions). Helluva fire at berm of paved county road. Enflamed tires, gasoline, paint, etc resulted in complete consumption of vehicle, and of all plant life. (As charred carcass of motor cycle was lowered into bed of into pick-up by front-end loader on a John Deere it invoked imagines of a giant mechanical cat holding an incinerated metal rat.) This bemused photographer (incident was "just deserts" for a loud-mouth, speed limit-violating punk) returned to crash scene in July (six or seven week following wreck) and ,with Nikon and Kodachrome, recorded for posterity the forgiving nature of vegetation and onset of plant succession.

Ground zero of the inferno was now the scene of textbook Clementsian invasion with establishment of the annual forb, toothed spurge (Euphorbia dentata) and annual goosegrass (Eleusine indica) from the soil seed bank and vegetative recovery of the perennials, Johnsongrass (Sorghum halapense) and common bermudagrass (Cynodon dactylon) from rhizomes. All four species are aliens (exotics). Annuals are of the therophyte and perennials of the hemicryptophyte or cryptophyte life forms (Raunkiaer, 1934). The potential natural range vegetation of this habitat is a black oak (Quercus velutina)-dominated forest with an understorey of big bluestem (Andropogon gerardii) as dominant and various other grasses like purpletop (Tridens flavus) and poverty oatgrass (Danthonia spicata) as associate species. (See the immediately succeeding slide/caption set.)

The climax plant community for this environment was obvious from range vegetation present on the other side of this county road (next slide). The preburn plant community present on spot of motor cycle crash site was bermudagrass, Johnsongrass, and hairy crabgrass (Digitaria sanguinalis) that was maintained by infrequent mowing. In less than two months after incineration in late spring most of the pre-burn naturalized plant species had reestablished. It was as if nothing had happened.

Lesson here is that plant responses to disturbance depend on any number and extent of variables, but responses to defoliation are similar regardless of defoliating agent (fire, natural or man-caused; range animal; drought; hail, wind, mechanical mower; plow; or human foot traffic). Yes, the innocent bare feet of children on the school playground can have the same general impact as the motor cycle fire, plowing, or overgrazing. This depends on the defoliation factors of intensity, season, frequency, selectivity, and extent or area. For example, it might have taken bermudagrass longer to reestablish after the firry crash if the area of burn had been larger so that new shoots from rhizomes and/or stolons had to grown greater distances.

The fact is that while standard categories of range plants based on responses to defoliation (eg. decreasers, increasers, invaders) will vary to some degree with things such as animal species (selectivity), the general response of plant species is much the same to any and all agents of defoliation. In the classic work by Weaver (1954) and Weaver and Albertson (1956) species that decreased first and fastest under overgrazing also decreased first and came back last in response to the Great Drought (eg. big bluestem). Likewise, those species that persisted longest under overgrazing survived longest in prolonged drought (eg. cactus like Opuntia sp.). A reckless motor-cyclist provided an example of that ecological fact of range life.
A'rum, a'rum!

Ottawa County, Oklahoma. July.

167. End game- The potential natural (= climax ) vegetation of the range site at of the scene of a motor cycle crash included herbaceous species the dominant of which was big bluestem seen here as the darker green cespitose plants. At this early spring season plants of big bluestem were still or short stature (slaightly over a foot in height). The other grass (the more abundant plants appearing as yellowish green in color) in this "photo-plot" of the climax herbaceous zone was poverty oatgrass. Though a member of the climax vegetation for this range site, poverty oatgrass was an increaser "side-kick" to the decreaser tallgrass species.

This was the herbaceous understorey of an upland Ozark Plateau savanna to open forest dominated by black oak. This is the climax vegetation to which the seral plant community at the motorcycle crash scene shown immediately above was progressing.

Ottawa County, Oklahoma. Early June; grain-ripe stage of poverty oatgrass.

168. Decomposers as well as producers- A portion of the understorey of a black oak-dominated open forest with a seedling of black oak, lichen growing on decaying black oak branches, poverty oatgrass, and the fruiting bodies (= caprophore) of the mushroom or toadstool known as Frost's bolete (Boletus frostii).

Ottawa County, Oklahoma. Early June.

169. A fungus on the floor- The caprophore or fruiting body of Frost's bolete growing on the floor of a black oak-dominated upland forest with an open canopy (the structure/form of this tree-dominated vegetation verged on being a savannah). This caprophore was growing close to the fruiting body shown in the immediately preceding photograph. The cap of this mushroom measured more than seven inches across (the unfolded stockman's knife was seven inches).

Technically speaking this bolete is edible, but it can cause stomach upsets.

Ottawa County, Oklahoma. Early June.

170. Oak-hickory forest and savanna— This is the widespread transition zone or intermediate community type between actual oak-hickory tallgrass prairie understory savanna and the western edge of the oak-hickory forest proper.Post oak and black hickory dominate the tree layer while black and red oak are associated species. Understory is primarily nodding or Canada wildrye and purpletop (Tridens flavus). Virginia creeper covers much of the understory and climbs into tree tops. Blackberry, buckbrush, Mayapple, and black-eyed susan dominate various microsites depending on cover of tree canopy. Chert savanna-chert forest composite type with fire determining which form prevails. June, late vernal aspect.

FRES No. 15 (Oak-Hickory Ecosystem). K-73 (Mosaic of Bluestem Prairie [K-66] and Oak-Hickory Forest [K-91]). SAF 52 (White Oak-Black Oak-Northern Red Oak) but with black hickory more than black oak; SRM 801 (Dry Savanna). Oak-H:ickory Series of Brown et al. (1998).

171. Winter twigs of black, Ozark, or Texas hickory (Carya texana)- Two examples of twigs of one of the smaller, commoner, and more wides pecies of hickory in the Ozark Plateau. Black hickory is a major and, often, a dominant tree in the western portion of the oak-hickory forest as well as the oak-hickory-tallgrass savanna.

Most of the various Carya species are extremely difficult to distinguish based on leaf, bark, and even fruit characteristics. One of the more useful groups of features for identification of the different hickories is characteristics of winter twigs, especially the terminal bud. These photographs presented winter twigs of Ozark or black hickory overall. The next two photographs showed more details with emphasis on terminal buds.

Ottawa County, Oklahoma. December; winter dormancy.

172. More specifics of winter twigs of Ozark hickory- Following presentation of the general winter twig of Carya texana in the preceding set of slides these two photographs displayed greater detail, particularily of the terminal bud, using two more examples from the same stand on an Ozark Plateau savanna.

Ottawa County, Oklahoma. December; winter dormancy.

173. Texas or black hickory- Summer leaves and growing nuts of Texas or black hickory in the Springfield Plateau section of the Ozark Plateau Region. Note pointed and longer leaves with small though prominent serrated leaf margins. The tree of these leaves was grrowing beside the mockernut hickory shown in the next slide.

Ottawa County, Oklahoma. Early July; immature fruit stage.

174. Mockernut hickory- Early summer leaves and rapidly growing, immature nuts of mockernut hickory in the Springfield Plateau section of the Ozark Plateau Region. Note the eliptical-shaped leaves with nearly smooth margins. The tree on which these leaves were grrowing stood beside the Texas or black hickory shown in the preceding slide.

Ottawa County, Oklahoma. Early July; immature fruit stage.

175. Babies of three dominants- Seedlings of blackjack oak (Quercus marilandica), Texas or black hickory (Carya texana), and post oak (Q. stellata) left to right, respectively. These three tree species are the tri-dominants of both the western oak-hickory forest in the Ozark Plateau physiographic province as well as of the Cross Timbers of northern Oklahoma and southern Kansas, a climax oak-hickory-tallgrass savanna that is contiguous with the tallgrass prairie of the Osage Questas section of the Central Lowlands physiographic province.

The grass in between post oak seedlings in foreground and in the distant background was poverty oatgrass (Danthonia spicata), a climax species for this forest range site. This was on an extremely rocky, south slope in the Springfield Plateau portion of the Ozark Plateau.

Ottawa County, Oklahoma.

176. Oak-hickory-tallgrass savanna (chert savanna) reclamation by prescribed fire- The Ozark Mountains (the Springfield Plateau portion of the Ozark Uplands or Ozark Plateau) vegetation shown here is the first stage of restoration of a pre-white man oak-hickory-tallgrass savanna that in absence of natural fire regimes developed into a post-climax anthropogenic ("man-made") oak-hickory forest. The original pre-white man Ozark savanna vegetation such as that described by the various authors cited above (eg. Schoolcraft, 1821) was generally a savanna (or at best an open canopy woodland) with an open canopy of widely spaced oaks (post, white, blackjack, black, red, the latter common name being somewhat confusing but here referring to Quercus rubra var. rubra) and species of hickories including bitternut or pignut hickory (Carya cordiformis), shagbark hickory (C. ovata), black or Ozark pignut hickory (C. texana), and white or mockernut hickory (C. tomentosa). The strata of vegetation below the trees included seedlings and saplings of the trees, tall and mid-height prairie grasses, forest and grassland forbs, and understory shrubs of various sizes and growth forms.

This savanna— as are all savannahs by definition —was a transition zone between a biome dominated by woody vegetation such as forest and a grassland biome. Most of the vegetation of the western Ozarks was a savanna between the oak-hickory form of the eastern deciduous forest and the tallgrass prairies (eg. the large Cherokee Prairie) to the west.

As described in some detail earlier in this section on Ozarks savanna, white settlers or white sedentary farmers (not to be confused with the white frontiersmen known as backwoodsmen who were a combination of hunters- trappers, open range stockmen, and farmers "rolled in to one") were fearful of wildfire and established effective (too effective for sound ecological management of native vegetation) fire exclusion from the Ozark savannahs. These transition communities— as is the case for almost all true savannas —were fire vegetation types and "protection" from fire resulted in deterioration of the vegetation (departure from climax) such that pre-Columbian oak-hickory-tallgrass savannahs "thickened up" into oak-hickory forests with multi-layers of woody plants comprised of all age classes of the dominant oak and hickory trees as well as the native understory shrubs such as flowering dogwood, redbud, hazelnut (Corylus americana), and hop hornbeam (Ostrya virginiana) as well as woody vines and colony (patch)-forming woody plants like blackberry. Almost eliminated from this "protected from fire" vegetation were the native herbaceous species (and their layers of vegetation) except for such vernal species as May apple (Podophhyllum peltatum). The native grasses were the species that were most excluded by the enhanced regeneration of trees as a result of fire exclusion. These included tallgrass species such as the dominant decreasers (big and little bluestem, Indiangrass, Canada and Virginia wildrye) and increasers (eg. purpletop), all of which were "headquartered" in and spread out from adjoining prairies. Climax grasses also included forest species like woodreed grass (Cinna arundinacea) and beak grain (Diarrhena americana).

After 50 to 100 plus years of this unnatural fire exclusion, the savannas in many locations became almost "jungle-like" often approaching impenetrable thickets formed by: 1)the varying sizes of the oak and hickory seedlings and saplings, 2) the upper layer of shrubs like dogwood and redbud, 3) variouspatches of blackberry or buckbrush with all these "tied together" by 4) lianas (= woody climbers) like grape (Vitis spp.), Virginia creeper (Parthenocissus quinquefolia), poison ivy (Rhus radicans=Toxicodendron radicans), and trumpet vine (Campsis radicans). There was also a great increase in saplings and young trees of fire-susceptible tree species, especially black cherry (Prunus serotina).

This tangle became a home for the white man's feral, mast-eating hogs (spelt "hawgs"). These acorn-eaters became famous (or infamous depending on proclivity of the individual hillbilly) as the Arkansas razorback, the equivalent of the Texas longhorn, but the forest range was of limited value to any other grazer or browser, including native whitetail deer and, especially, elk.

Utility and "beauty" of these "saved from fire", Smokey Bear-forests also depended on the value systems and perspectives of different mountaineers and visitors (ie. "foreigners"). In as strict ecological sense, however, these vegetative tangles or "triple-canopy woods" were disclimaxes to use the Clementsian term. The forester might view these newly formed forests as natural forests amenable to silvicultural and forest management practices while the stockman bemoans loss of grazing capacity on former savanna ranges.Thus, whether the changes were for the better or for the worse depends on one's personal preferences based on commodity produced, attitude toward "beauty" or aesthetics, favorite pastimes, and so on. This particular example from the Ozarks illustrated human x environment interaction such that it might even "…make it probable that there is no such thing as a 'natural landscape'" (Carter, 1968, ps. 397-398). However, the ecological concept of a disturbance climax is scientifically valid. The preservation, conservation, and management of potential natural vegetation in this case necessitates actions known collectively as restoration, the most likely tool of which is simply the reintroduction of the environmental factor, the one component of climate, that man took out: fire. Now human co-action to restore what human neglect degraded requires as the tool of scientific management prescribed fire at regimes simulating those that occurred before Smokey Bear barged into "them thar hills".

Such restoration was "caught on film" in this and the next slide. Prescribed fire was used on this portion of a savanna-turned-forest five years prior to time of this photograph. Many of the oak and hickory trees as well as the less fire-tolerant species like black cherry were killed outright or only top-killed and resprouted, but both 1) total tree (canopy) cover and 2) cover of dominant climax tree species were reduced. However, cover and density (= regeneration) of seral tree and shrub species increased exponentially. The greatest increase was in sassafras followed by persimmon, smooth sumac, and blackberry, all of which are seral species. The two climax understory shrubs on sites like this are flowering dogwood and redbud. Redbud was released by prescribed burning (a specimen in front center of slide). There was also an increase in such climax decreaeser species as peaked panicgrass (Panicum anceps) and numerous tick clovers (Desmodium spp.), but there was also an increase in some invader species like broomsedge bluestem. Climax tallgrass species like big bluestem and Indiangrass had not yet emerged to any extent (again, five years post prescribed burn).

Dominant trees in this local stand were black oak (two trees at far left) and white oak (center tree).

FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Oak Savannna). SRM 801 (Savanna). SAF 64 which is Sassafras-Persimmon, a seral forest cover type. SAF designation misleading for three reasons:

1) this is a savanna dominated by black oak but not a black oak forest (ie. SAF designation based on the dominant species [climax in this instance] implies forest when technically the potential natural vegetation is not forest but savanna: the key or distinguishing feature is not species composition or dominant species but tree density and/or degree of canopy cover),

2) black oak and white oak are co-dominant but the former slightly more so (at least aspect dominance-wise) such that the designtion of black (instead of white) oak to conform with SAF single species forest cover type name was arbitrary, and

3) SAF 110 (Black Oak) was converted into SAF 64 by prescribed fire.

Chert Savanna. Ozark Highlands- Elk River Hills Ecoregion, 39c (Chapman et al., 2002). Savanna State Park. McDonald County, Missouri. July.

177. Degraded Ozark oak-hickory-tallgrass savanna (chert savanna) treated by prescribed burning- A natural chert savanna in the "tension zone" (= transition) between the oak-hickory form of the eastern deciduous forest and the tallgrass prairie was subjected to fire suppression (= underburning) for approximately four to six decades with result that tree regeneration was excessive (ie. at rates far in excess of natural recruitment, hence a woody invasion of the understory) and the savanna was converted into an anthropogenic forest. Vegetation specialists with various agencies of the state of Missouri wished to restore the climax or natural (the pre-settlement) savanna vegetation of this western Ozark Uplands or Ozark Plateau (specifically the Springfield Plateau). Prescribed fire was chosen as the tool of vegetation modification (restoration) by attempting to return the natural (pre-fire suppression action) fire regime(s).

Vegetation seen here was five years after the first prescribed fire (and probably about a half century since humans last "set the woods afire", which was legally arson at that time).

The two immediate results from the first prescribed burn were: 1) killing of some mid-size trees (trees of middle age clsasses) and top-killing (and subsequent resprouting) of younger trees and saplings and 2) release of seral tree species, especially sassafras and persimmon, and seral shrubs like smooth sumac, blackberries, and buckbrush. The dominant trees were black oak and white oak. Both suffered fire damage ranging from slight to severe at a local or microsite scale. Beaked panicgrass and broomsedge bluestem (the grass in the immediate center and left foreground) were released and increased substantially following fire, but climax tallgrass species like Indiangrass and big bluestem had not responded at time of photograph (five years post prescribed burning). The two dead trees in center are a black oak and a white oak.

FRES No. 15 (Oak-Hickory Woodland Ecosystem), K-72 (Oak Savanna). SRM 801 (Savanna). Irrelevance of SAF cover type designation was discussed under immediately preceding slide. Ozark Highlands- Elk River Hills Ecoregion, 39c (Chapman et al., 2002). Chert Savanna. Savanna State Park, McDonald County, Missouri. July.

Sassafrazled- Three "photo-collections of leaves of sassafras (Sassafras albidum) growing on a tallgrass prairie-black oak-dominated forest in the western Ozark Plateau in northeastern Oklahoma. These leaves were on three-year-old shoots in a local colony of sassafras that developed on a local disturbance. Viewers can fairly easily find all three leaf forms of leaf margins in these examples.

These young leaves still had their new leaf light green color. This coloration can be compared to the darker, richer green of older leaves presented in the next two slides ...

Ottawa County, Oklahoma. Early June.

178. Can you spot the three forms of margins?- The three margin forms of sassafras leaves were growing on this leader on edge of a black oak-dominated forest and tallgrass prairie in the western Ozark Plateau.

The dark-green color and harder leaf surface can be compared to that of younger leaves in the immediately preceding three-slide set.

Ottawa County, Oklahoma. Late July.

179. Inflorescence of sassafras (Sassafras albidum)- Sassafras is a member of the very small laurel family (Lauraceae). Interesting, another member of this tiny family is spicebush (Lindera benzoin), a forest shrub of lower vegetation layers, which also grows in the oak-hickory forest but usually on bottomlands and not in close association with this upland species. Examples of spicebush can be viewed with the other shrubs of the oak-hickory forest under that series of slides (Woodlands & Forests).

Sassafras is typically a dioecious species which also reproduces asexually from widely spreading, horizonal roots (termed rootstocks by some authors). This root-sprouting feature results in formation of large colonies of sassafras much like quaking aspen (Populus tremuloides), sumac (Rhus species; see below), and wild plums (Prunus species). These roots are dug and pulled (often with the aid of tractors) and later boilded to make sassafras tea, one of the greatest elixirs known to mortal man and a beverage just this side of ambrosia.

Sassafras oil was once the "active ingredient" (ie. main flavoring) of root beer and the similar, sweetened, carbonated beverage known as sarsaparilla. Later, of course, synthetic forms of this flavoring were manufactured commercially and this more economical artificial flavoring replaced the genuine article. Real hillbillies-- like your author-- still drink tea made from sassafras roots (the bark is the source of the flavor). Oil of sassafras does contain safrole which can be toxic. The Food Drug Administration (FDA) had to get into the act and in it's scientific and unerring wisdom determined that oil of sassafras was a potential carcinogen. (The FDA could make things easier if it awarded a competitive grant to some elite university to see if it could discover one thing that is not a potential carcinogen.)

Oak-hickory forest-tallgrass prairie ecotone in Ozark Plateau. Ottawa County, Oklahoma. April.

180. Leaves and fruit of sassafras- Fruit of sassafras is a major feed source for passerine and upland game birds (eg. bobwhite quail). The twigs, including buds, are frequently a major source of browse for whitetail deer (Crawford et al., 1969, 215). For this, as well as numerous other reasons, the sassafras-persimmon forest range cover type (SAF 64) is extremely valuable for wildlife, probably more so (for more species anyway) than the climax forest cover types in the same regions.

Sassafras has several leaf shapes (on the same tree) ranging from entire (not lobed) to one-, two-, three, or even five-lobed.

Sassafras is primarily a seral species, often invading early in secondary succession following pioneer (especially annual) species. It becomes locally abundant on old-fields (abandoned crop fields), cut-over forests (especially after clear cutting), and forest glades that are not subject to frequent fires. Sassafras will grow into a small tree or, alternatively, it may persist as thickets of shrubs when subjected to frequent fires and/or mowing. Disturbances like logging, forest fires, wind throw, and ice storms (anything that reduces cover of climax tree species) increase density and cover of sassafras (and associated species like persimmon) and improve habitat for certain species of wildlife. Conversely any such disturbances that reduce the climax oaks and hickories (and other potential natural dominants) reduce quality of habitat for most tree-dwelling wildlife such as squirrels, coons, and cavity nesting birds. Livestock (other than brush goats) do not usually browse sassafras.

Ottawa County, Oklahoma. September.

181. Trunks of sassafras- These four boles are modules of a fairly large sassafras showing typical bark and habit of this clonal species. Edge of oak-hickory forest. Ottawa County, Oklahoma. Autumnal aspect, early December.

182. Persimmon (Diospyros virginiana)- This member of the ebony family (Ebenaceae) can grow into a large tree that at maturity rivals in size neighboring oaks and hickories. More characteristically persimmon stays shrub-size like those shown in this colony. Some of this variation (and confusion caused by it) may be due to taxonomic varieties and various forms (Steyermark, 1963, ps. 1175-1176). Persimmon is usually dioecious and, as shown below, produces some of the most delicious fruit of any North American tree. It also reproduces asexually and this is often the more effective form. "Persimmons, like Sassafras, spread vegetatively by the formation of suckering surface roots, eventually forming thickets. These colonies or clones show similarities of branching and a general uniformity of habit and growth" (Steyermark, 1963, p. 1176).

The inside of one such colony was shown here in the West Cross Timbers of central Texas (Erath County). October. Most of the understorey grass was little bluestem. The clonal habit of both persimmon and sassafras along with their primarily seral role or status in plant succession likely explains their close association with one another as in the sassafras-persimmon cover type (SAF 64).

183. Leaves of persimmon- Lower branchlets with leaves on lower trunk of common persimmon. Leaf color in the first or upper slide is correct (accurately reprodued from Fujichrome Provia 100F film) whereas leaf color in second or lower slide was incorrectly or inaccurately reproduced by an Epson Perfection 600 scanner. The scanner produced washed out or white portions of leaves as if bright spots of sunlight had created different tones. This was not the case at all; both of these photographs were taken under an overcast sky within a minute or so of each other. There were absolutely zero shadows or sunlite spots on leaves. Adobe Photoshop color adjustment could not completely restore scanner-botched color back to original as captured by Provia 100F. Do not buy Epson products!

Too late for this photographer, and besides viewers get the idea as to what leaves of common persimmon look like. As with all images of gross plant morphology readers can consult standard manuals, flora, silvic treatments, even some detailed field guides for descriptions of plant parts. For common persimmon in "these here parts" of the Ozark Plateau the excellent reference by Kurtz (2003, ps. 148-149) was recommended.

Ottawa County, Oklahoma. Early Ju;;ne- full-bloom stage (although flowers were not visible at this size/scale, staminate (male) flowers were at peak anthesis in these images).

184. Inflorescence of persimmon- This flowers on this branch of the usually dioecious persimmon were all females. Ottawa County, Oklahoma. May.

185. Plentiful harvest of persimmon fruit- This is the essence of hog-heaven (for hogs, 'possums, and hillbillies). Fruit and leaves of a female persimmon growing in the West Cross Timbers of central Texas that yielded a bumper crop. Persimmon is one of the most distinctively flavored and admired fruits native to North America (at least for those with character enough to appreciate them). In addition, persimmon is one of the most dependable-yielding of all native fruit trees.

Erath County, Texas. October.

186. Fruit of persimmon- Appearance of persimmons approaching ripeness (and everyone learns to wait until persimmons are "good and ripe"). With a bowl of persimmons and a cup of hot sassafras tea a body is ready to partake of pleasures having few parallels. Such enjoyment has been known to bring grins like as to the countenance of a marsupial (Didelphis virginiana) masticating feces.

Erath County, Texas. October.

187. Features in old adults- Trunks of two shoots of persimmon (first slide) and details of bark on a third persimmon trunk (second and third slide) in early winter in the western Ozark (Springfield) Plateau. Ottawa County, Oklahoma.Late December.

There are rwo or three genera and several species (depending on which authority was consulted and if that author was a "lumper" or "spliter") within the cashew or sumac family (Anacardiaceae) that are widely distributed within the tallgrass prairie, oak-hickory forest, and ecotonal savannas "sandwiched" amongst these immense climax communities and their various cover types. The latter includes the Prairie Peninsula, tallgrass-oak-hickory savanna, and Cross Timbers. Several of these were presented immediately below. It should be borne in mind that some of these species also grow in other range cover types that are not conterminuous with the dominance types presented in this section. These species have discontinuous or disjunct ranges (ie. not contiunuous or contiguous). In a less technical expression these are interrupted or "spotty" distributions where the spots are nonconterminuous regions.

For example, skunkbush sumac (Rhus aromatica= R. trilobata) is a common shrub in the tallgrass prairie and adjoining Cross Timbers and also variously throughout the mountain scrub or petran shrublands (the "soft chaparral") of the southern Rocky Mountains, especially the Front Range. Skunkbush is also a locally important browse plant from New York to northern Alberta. Smooth or shining sumac (R. copallina= R. copallinum) is widely distributed in the oak-hickory forest of the Ozark Plateau; tallgrass prairies like the Cherokee Prairie, Osage Questas, Flint Hills, and Grand Prairie; and the Cross Timbers. Skunkbush is also locally abundant in the shrublands and shrub savannas of the Wastach Range, one of the westernmost reaches of the Rocky Mountains, and along the Atlantic Coast from New York to Florida.

The presence of three to five Rhus species (again, depending on taxonomic treatment) within a single range cover type (eg. Cross Timbers) was a good example of Darwinan fitness (natural selection) and speciation.

All of the Rhus species (except for the climbers perhaps) are clonal shrubs that form colonies by means of shallow horizonal roots (often called "rootstocks") known as "thickets" to cowboys, birdhunters, berry pickers, and other outdoorsmen. Rhus species are some of the few woody species in North American forests and ranges that actually increase under burning. In fact, Rhus is one of the very few genera of shrubs that are not reduced by grassland and surface forest fires. Fire actually rejuvenates old "decadent" stands as well as making the twigs, leaves, and buds more available to livetock and game, that is those species valuable as browse such as skunkbush. The fruit of all Rhus species is eaten by many species of birds and it is a safe asumption that the twigs and buds are taken periodically by all species of cervids within the ranges of these shrubs. Crawford et al. 1969, p. 209) ranked Rhus species as "the fourth most important deer food in Missouri" based on estimated quantities consumed.

There are several good references for members of the Anacardiaceae. One of the most practical, interesting, and time-tested was Vines (1960, ps. 629-641).

Students interested in the different types of species distributions were sent to Polunin (1960, ps. 182-197).

188. Smooth, scarlet, white, (and a half dozen other common names) sumac (Rhus glabra)- This is one of the more common Rhus species in the eastern deciduous forest and eastern tallgrass prairies. It is of relatively little browse value, but is a widely distributed shrub that is a component of both climax and seral communities though it is often more abundant in the latter as it benefits from disturbances like fire. Smooth sumac is found in the oak-hickory forest, tallgrass prairie, Cross Timbers, and even Rolling Plains and Edwards Plateau of Texas.

Smooth sumac can grow to heights resembling that of a small tree which, when combined with unusually wide distances among shoots, it has sometimes been regarded.

Both of these photographs were of the apex of a single shoot of this thicket-forming species. The first slide (taken in early June) showed the inflorescence while the second (late June) presented the cluster of fruit and illustrated the alternate, whorled arrangement of compound leaves coming directly off of the shoot. Newton County, Missouri and Ottawa County, Oklahoma (contiguous counties) for first and second photograph, respectively.

189. Smooth and slick- An immature fruit cluster of smooth sumac in the Ozark Plateau. This one was growing in a fence row at edge of a small bluestem meadow routinely mowed for prairie hay. Newton County, Missouri. Mid-July.

190. Winged, dwarf, flameleaf, or shining sumac (R. copallina= R. copallinum, most commonly treated as variety latifolia)- Shoots with inflorescences of another multi-named sumac that has a wide distribution. It grows in the longleaf pine forest of Louisiana, Cross Timbers, tallgrass prairies, and eastern deciduous forests types from eastern Canada and Maine southwestward. As suggested by the common noun, dwarf, winged sumac is generally smaller than smooth sumac.

Both slides were taken in an oak-hickory-tallgrass savanna. Ottawa County, Oklahoma. June.

191. Seen up close- Detailed, close-in view of flowers of winged, dwarf, shining, or flameleaf sumac. Newton County, Missouri. Mid-July.

192. Fruit of winged or dwarf sumac- Not only are these fruits taken by both song and game birds (and undoubtedly by small mammals once fruits fall to ground), but they are also consumed by humans in the form of a "mountain or pink lemonade". Ottawa County, Oklahoma.

October.

193. Prairie or lance-leaf sumac (R. lanceolata= R. copallinum var. lanceolata)- This is probably the sumac that is best adapted to the less mesic range sites and types of the eastern deciduous forest and central prairies. It is one of the more abundant Rhus species in the Western Cross Timbers thence south and west into the Edwards Plateau. This specimen was growing deep in a stand of post oak and blackjack oak-dominated Cross Timbers in Erath County, Texas. May.

194. Skunkbush, skunkbush sumac, or fragrant sumac (R. aromatica= R. trilobata)- This is the most valuable species of Rhus for browse. In addition, it is one of the most widely distributed shrubs in North America. It grows in oak-hickory forests, oak-hickory-tallgrass savannas (eg. Cross Timbers), Rocky Mountain scrublands, in the Hudson Valley of New York, south into Mexico, and in the Canadian north from Quebec to Alberta. It is more readily browsed by small ruminants like goats and deer than by cattle or horses. Dayton (1931, p. 96) reported that browse value ranged from worthless to good and that it was "as a rule, being largely untouched by livestock". Lemonade is also brewed from the fruit of the species such that has been called lemonade sumac.

Western Cross Timbers. Erath County, Texas. June.

195. Skunkbush sumac at peak bloom- This shapely specimen of skunkbush was in full-flower on the Palo Pinto form of Western Cross Timbers. It grew at base of a post oak, the dominant species of the Cross Timbers. Lake Mineral Wells State Park. Parker County, Texas. March (vernal aspect).

196. Flowering shoots and inflorescences of skunkbush- Details of a flowering leader of skunkbush (including characteristic leaves) and close-up of the rather delicate inflorescences. Lake Mineral Wells State Park. Parker County, Texas. March (vernal aspect).

197. Leaves and fruit of skunkbush sumac- These two slides show immature fruit (first picture) and mature fruit (second picture) as well as the variation in leaves in this species. The first photograph was taken in a subhumid zone (Erath County, Texas; in June) and the second photograph was taken in a humid zone (Ottawa County, Oklahoma; in May). Note the larger leaf size in the more mesic environment.

198. Poison ivy (R. radicans= R. toxicondendron= Toxicodendron radicans)- Once again the authorities cannot agree on the correct one-- and only one-- species name of this woody climber. Many people would agree that it causes severe skin irritation in them or ones they know. Aside from this distinction (which is certainly not a factor for all folks) poison ivy is valuable for some species of browsing wildlife such as deer and the fruit is eaten by many species of birds including wild turkey and bobwhite quail.

Like the other Rhus species, poison ivy appears to occupy an ecological niche that cuts across several successional stages. It seems to occur frequently on mid-seres of once-denuded habitats like old-fields and abandoned trails or lanes, but it is also one of the most common shrubs in climax deciduous forests notably the oak-hickory association types (and most forest sites therein). Poison ivy is especially common in older fencerows protected from mowing. Poison ivy is an attractive woody vine, but the allergic reaction of many people limits it's usefulness for ornamental purposes. This does not detract from it's beneficial roles as a native plant for aesthetics, wildlife (both browse and cover), and ecological roles (perhaps facilitating plant succession).

This handsome specimen was growing on a dead elm (Ulmus sp.) trunk in an old fencerow. This was an example of the utility of fencerows as prime wildlife habitat. Ottawa County, Oklahoma. May.

199. "leaves of three let me be"- The poetic warning regarding poison ivy for those who are allergic or do not know if they are allergic to this common and valuable shrub of the edge of oak-hickory forest and tallgrass prairie or, in most cases the hardwood-tallgrass savanna. This specimen was in the Springfield Plateau portion of the acncient Ozark Plateau.

Ottawa County, Oklahoma. Early June; peak bloom stage of phenology.

200. Leader and leaves of "let me be"- Leader (upper photograph) and flower cluster (lower photograph) of poison ivy aSpringfield Plateau portion of the acncient Ozark Plateau.

Ottawa County, Oklahoma. Early June; peak bloom stage of phenology.

201. An irritating (to some folks) inflorescences- Close-up photographs of the flower cluster of common poison ivy (R. radicans= R. toxicondendron= Toxicodendron radicans) growing in a fence row on a hardwood-tallgrass prairie savanna in Springfield Plateau portion of the acncient Ozark Plateau.

Ottawa County, Oklahoma. Early June; peak bloom stage of phenology.

202. Inflorescence of poison ivy- Ottawa County, Oklahoma. June.

203. Cluster of fruit of poison ivy- This is feed for a number of bird and small mammal species. In addition to listing wildlife species that use the other sumacs, Martin et al. (1951, ps. 336-337) listed separately the poison ivy and oak species (as Toxicodendron spps.). Ottawa County, Oklahoma. December.

The vegetation of the eastern deciduous forest cover types and the ecotones situated among these types (eg. oak-hickory forests) and the central grasslands, expecially tallgrass prairie, include numerous kinds of woody vines or woody climbers. This category or form of shrub is often termed a liane or liana when applied to tropical vegetation and, less commonly, to forest vegetation in temperate regions. Lianas of the deciduous forests and their ecotonal savannas like the Cross Timbers include vines of grape, poison oak, Virginia creeper or woodbine, and, among numerous others, greenbriar (Smilax spp.). The latter are some of the most bothersome to people and livestock moving about in these plant communities. Greenbriar species provide coverts and shade for wildlife and browse for both wildlife and livestock when the shoots are "young and tender" (ie. before the prickles and/or spines harden and become sharp).

Smilax species are monocotyledons. Usually they have been placed in the Smilacoideae (subfamily) of the immense and extremely diverse lily family (Liliaceae), but some authors have put them in their own family (Smilacaceae). Smilax species usually form dense colonies with new shoots arising from woody rhizomes. These patches are the most impenetrable of all thickets in the vegetation in which these species grow. For instance, blackberry briar patches are a cakewalk by comparison.

Two of the more common Smilax species in tallgrass savannas were included to introduce this form or category of range and forest shrub (the soft-stemed species of Smilax would be designated forbs).

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