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In this author's view (including research experience) and consistent with a common consensus, the grasslands of California warrent separate designation and treatment unique to this geopolitical unit. This is the case for at least two major reasons: 1) they have been altered more by European man than any other grasslands in North America (especially annual grasslands and the closely associated annual grass-oak woodland type) and 2) the Mediterranean climate (and similar climatic regimes contiguous to it) that prevails over most of these grassland range types exists in North America only in California. A third but less obvious reason for distinctive treatment of California grasslands is that their variation from each other and their human-induced diversity exceeds that of grasslands in other major governmental entities (state, commonwealth, province).
California grasslands have long been and continue to be described and studied from perspectives of historic importance, ecological structure and function, and agricultural management (in the disciplines/professions of Range Management, Agronomy, and Forestry). Some of the more important published sources--and some of these are classic works that make for delightful reading--related to California grasslands (and associated marshes, meadows, and forest glades) were cited below. Relevant chapters in Terrestrial Vegetation of California (Barbour and Major, 1988; Barbour et al., 2007), including parts of chapters devoted to vegetation conterminous and forming ecotones with grasslands, remains standard fare. California Grasslands (Stromberg et al, 2007) is a wonderful compendium with encyclopedic coverage of the major (and some minor) grasslands in the Bear Flag State.
Originally the major grassland type in the Central Valley System and extending up into the foothills of the Sierra Nevada and throughout much of the Pacific Coast Mountain Range was prairie dominated by native perennial bunchgrasses. Traditionally grassland ecologist and practicing rangemen regarded those California grasslands occurring immediately along the coast and for a distance inland to which Pacific Ocean maritime influences modified the Mediterranean climate as distinct from those of the Central Valley, Sierra Nevada foothills, and inland slopes of the Coast Range. Nothwithstanding the continuity and likely general common origin of these grasslands they have historically been treated separately. In Terrestrial Vegetation of California (Barbour and Major, 1988), the state's vegetation "bible", valley (including foothill) grassland and coastal prairie (of the Californian and Pacific Northwest floristic provinces, respectively) were treated in separate chapters as was oak woodland range. This arrangement was continued in the third edition of the state's vegetation reference ((Barbour et al., 2007). The same (or nearly so) distinction of these grassland types was used in California Grasslands (Stromberg et al., 2007). Some but certainly not all of this separation reflected the more drastic anthropogenetic conversion of the virgin perennial bunchgrass prairie of valley and foothills into annual grassland, the California annual type. (Again, the two major types are parts of two floristic provinces.)
Consistent with this traditional and logical treatment, examples (remnants) of the bunchgrass prairie typical of the Central Valleys Region and inland Coast Ranges was kept separate from the coastal (maritime-influenced) grasslands. Clearly, some key grass species were common to both major grassland range types.
1. California Bunchgrass Prairie or California Steppe or Pacific Prairie- The pre-Spanish climax perennial grassland. A relict community still grazed by sheep that is dominated by purple needlegrass (Stipa pulchra), the State Grass of California. This native pasture often existed as a consociation of S. pulchra or sometimes this cespitose perennial was co-dominant with nodding needlegrass (Stipa cernua). Hopland Field Station, Mendocio County, California. May.
No SRM description of this pre-Columbian range type, the original major grassland cover type of California. The type should have been inserted as a separate distinct range type between SRM 214 (Coastal Prairie) and SRM 215 (Valley Grassland). It is the virgin vegetation that was thoroughly converted into FRES No. 42 (Annual Grasslands Ecosystem) of which SRM 215 is a man-induced type conversion, a disclimax (disturbance climax) form of the original needlegrass bunchgrass prairie. Stipa prairie could be designated as SRM 215A, but technically there is neither FRES or SRM designation for the original Stipa steppe. The Kuchler unit is K-41 (California Steppe). This is the most common form of the California perennial bunchgrass prairie which in turn has been interpreted as the Pacific slope form of the general bunchgrass steppe.
2. Detail of the sward of California bunchgrass prairie (a Pacific coast steppe)- The conspicuous monocot form in this needlegrass stand is a species of soap plant or amole (Chlorogalum sp.). California oatgrass (Danthonia californica) is a minor associate of this community. Oatgrass was probably the original major dominant of the North Coastal Prairie which is the second and smaller section of the California Bunchgrass Prairie. The oatgrass-dominated section is distinct from the needlegrass section of steppe and represents a transition between the Palouse and California perennial grasslands. Point Molate, Marin County, California. May. Native vegetation prior to permanent conversion to California Annual Grassland, SRM 215. Kuchler unit 41 (in human time-scale needlegrass steppe is no longer the potential vegetation).Though California annual grassland will not return to the original needlegrass climax through secondary succession this natural bunchgrass steppe does probably provide superior diets, quality wise, to range animals due to the longer green feed season characteristic of perennial grasses. It is also an interesting relict vegetation and natural pasture, especially to native plant enthusiasts. It is of no major economic importance.
3. Purple needlegrass, a Humpty-Dumpty dominant- This local "lone ranger" of the pre-Columbian climax dominant species of the California bunchgrass prairie was growing in a stand of little quakinggrass (Briza minor) that formed one of numerous patchs in a California annual grassland range. This example showed 1) the characteristic habit at full-flower stage of the cespitose Stipa pulchra and 2) that the native perennial bunchgrasses "ain't coming back" as the dominant in human (ie. management) time frame. Even a minor Eurasian grass, which is a fraction of the size of the original decreaser, dominates it; "... all the kings horses and all the kings men..." University of California Hopland Field Station, Mendocino County, California. May.
4. Scattered individual plants of purple needlegrass persisting in or invading into the anthropogenic disturbance climax of annual grassland. Denverton section of Maine Prairie in California Coast Range. June, and students should note that the native perennial species remained green longer than the naturalized Mediterranean annual grasses. One advantage of the native bunchgrasses that once dominated the California Prairie is the longer green feed (= higher-quality forage) period. Solano County, California.
5. Lone Ranger- An isolated purple needlegrass plant amid naturalized Mediterranean annual grass species. The dominant species was common wildoats which is a decreaser species such that it's dominance indicated either proper grazing (or, perhaps, light grazing or even absence of grazing). This degree of defoliation had allowed the grazing-sensitive former native species to grow to full, adult size.
It would be nearly impossible to overstate the ecological (= indicator) significance of purple needlegrass to the original or pre-Spanish Pacific Prairie. Weaver and Clements (1938, p. 526) specified that S. pulchra was the sole dominant of this association,and that this one dominant species "far overshadows all the others". In fact, this single plant species perhaps defined a major unit of climax (potential natural) vegetation more singularily than did any other species in any major plant community at the association-scale in North America. The fact that this species was nearly completely dispossesed of it dominance (other than as a rariety to the point of novelty) and cannot be brought back successionally does not in any way detract from its importance in historical, pre-Columbian (= virgin) vegetation.
June. Maine (Denverton) Prairie, Solano County, California.
6. Another form of California or Pacific Prairie- Cool-season perennial grasses comprising this local community are big squirreltail (Sitanion jubatum), California melic (Melica californica), and smaller portions of blue wildrye (Elymus glaucus). No FRES Number. K-41. SRM 214 ((Coastal Prairie) variant.
7. California annual grassland- As every third-year range major should know, the pre-Columbian California prairie or steppe just seen was converted into California annual grassland by European man by a combination of such phenomena as: 1) introduction of Mediterranean annual grasses and forbs, 1) overgrazing by Spanish (and later gringo) livestock, 3) drought, and 4) severe wild fires. This became a man-made (a zootic or anthropogenic) disclimax vegetation type; in classic Clementsian Ecology, a disclimax but essentially a permanent one incapable of return to the climatic climax of perennial bunchgrass steppe.
FRES No. 42 (Annual Grasslands Ecosystem). No Kuchler designation for non-native vegetation. SRM 215 (Valley Grassland). Annual Disclimax Series of Brown et al. (1998).
8. By August the annual forage turns to broom straw and footing becomes slick as glass. Hopland Field Station, Mendocino County, California. FRES No. 42 (Annual Grasslands Ecosystem). No Kuchler designation for annual grassland as Kuchler units are only ofpre- European vegetation. SRM 215 (Valley Grassland). Annual Disclimax Series of Brown et al. (1998).
9. The Coast Range in April- The Mediterranean annuals (both grasses and forbs) formed this new climax annual grassland (a disclimax that is permanent) throughout the Coast Mountain Range and Central Valley of California that has Mediterranean climate. As plant or seed agriculture replaced animal agriculture and spread into the valley, the now-annual grasslands were plowed under, first, for bonanza wheat farms and, later, forcotton, alfalfa, and horticultural crops to become the greatest, most intense agricultural area on Earth. This left annual grassland restricted to steeper sites as in the Coast Range and foothills of the Sierra Nevada. Altamont Pass, Alameda County, California.FRES No. 42 (Annual Grasslands Ecosystem). No K- unit. SRM 215 (Valley Grassland). Annual Disclimax Series of Brown et al. (1998).
10. Much of the "California annual type", as it is most commonly known to rangemen, occurs as an understory to the oak woodland. This constitutes another, separate range type known as the annual grass-oak woodland type. Both deciduous and live oak species are present. In this scene of the north Coast Range, interior live oak (Quercus wislizenii), California black oak (Q. kelloggii), and some valley oak (Q. lobata) predominate. In the Sierra Nevada foothills, blue oak (Q. douglasii) predominates with scrub oaks such as leather oak (Q. duranta) and Digger pine (Pinus sabiniana) being upperstory associates. FRES No. 28 (Western Hardwoods Ecosystem) and FRES No. 42 (Annual Grasslands Ecosystem). K-26 (California oakwoods) but no K- number for annual grassland. SRM 215 (Valley Grassland) variant, there being no SRM designation for the annual grass-oak woodland type.
11. Detail of the classic dominants of the California annual type- Wild oats (Avena fatua and A. barbata, the latter known as slender oats) shown here along with ripgut brome (Bormus rigidus or B. diandrus) are the decreasers of the annual grassland. As implied by its name, ripgut is mechanically injurious (though to eyes not the gastrointestinal tract). Wild oats are the most productive and nutritious of the introduced and now naturalized annual grasses. Soft brome or soft chess (Bromus mollis) vies with wild oats as desirable forage, but it’s response to disturbances like grazing is more characteristic of an increaser. The crucifer growing here is black mustard (Brassica nigra), the Spanish-introduced spice or drug crop gone wild. It became the dominant new climax forb closely associated with wild oats.According to accounts recorded in his Ph.D. dissertation, L.T. Burcham (1957, republished 1982) reported that the Spanish vaqueros made “runs through the mustard” gathering wild cattle. By the way, Weaver and Clements in the first edition of Plant Ecology (1929) clearly stated that the annual grassland was “of such permanence as to simulate a subclimax” (the same term they used for tallgrass prairie relative to true prairie as noted above). By the second edition of Plant Ecology , Weaver and Cements (1938) had designated annual grassland as “a disclimax of California annuals of such permanence as to simulate a climax”. Disclimax it will be recalled was the Clementsian designation of the buffalograss-blue grama short-grass plains. In other words, it was textbook knowledge 70 years ago that California annual grassland was a naturalized climax range type. San Joaquin County, California. April. FRES No. 42 (Annual Grasslands Ecosystem). No Kuchler unit. SRM 215 (Valley Grassland). Annual Disclimax Series of Brown et al. (1998).
12. Ripgut brome- This Eurasian annual grass though mechanically injurious is the dominant species of the disclimax (anthropogenic) California annual grassland under lighter grazing regimes. It is possible and practical to judiciously manage grazing so as to maintain populations of ripgut and wild oats, the most productive forage grasses of the annual type, and avoid eye or skin damage to cattle and sheep. The abundant spikelets with long, barbed awns and lemmas having sharp calluses at the seed-ripe stage have given this Mediterranean bromegrass the common names of needle brome and devilgrass. In spite of these features (and a bad reputation) ripgut can contain 15% crude protein at bootstage when it "is relished by cattle" (Sampson et al., 1951, p. 40). Hopland Field Station, Mendocino County, California, May.
13. Mature plant of ripgut brome- This is an example of one of the most valuable forage grasses of California annual range at full maturity showing characteristic habit. This specimen was growing in northcentral Texas and not on California grassland which was instructive in showing the geographic distribution of another of the widely distributed annual Eurasian Bromus species. It also illustrated similarity of southern continental climate characterized by mild winters and long, hot summers (sometimes interpreted as subtropical-like) to the Mediterranean climate of the Coast Ranges and Central Valley of California. Individuals of ripgut (and wild oats) do not reach as large a mature size under mild continental climate as under Mediterranean climate. This typical Texas specimen was less than two feet in height, but it had 46 tillers, almost each of which had an inflorescence. This "stooling" (= tillering) habit and the comparatively high nutritive value of it's plant tissue make ripgut brome one of the most valuable sources of feed on California annual range.
However, ripgut (or, more precisely, livetock on ripgut ranges) must be managed carefully. Animals should be moved off of ranges having dense populations of ripgut brome once this species reaches this mature state of development (ie. seed ripe phenological stage). At this, and especially seed shatter stage, ripgut becomes mechanically injurious. Next slide, please.
14. Spikelets of ripgut- A portion of the panicle of ripgut brome was photographed at onset of seed shatter stage to show individual spikelets and the awns on the lemmas. These slightly barbed but long extensions of the mid-rib or mid-vein of the lemma can be mechanically injurious. They are capable of penetrating the skin around nostrils and eyes (even working into eyes, especially the corners of eyes) and causing irritation and even infection. Besides which, at this advanced state of maturity overall forage quality will quickly approximate that of straw. It is time to change range for cows and calves (or ewes and lambs) or ship stockers. Erath County, Texas. April.
15. Stand of wild oats (Avena fatua) on California annual grassland in the northern Coast Range- This is a decreaser species of the naturalized annual range at peak standing crop (grain in soft dough stage). Taken on balance (a combination of herbage yield, forage nutritive value, freedom from toxins or mechanically injurious features, palatability to a wide range of range animals) wild oats is the single best naturalized grass on California annual range. It should be cherished by all California rangemen. (This species also naturalized in much of Texas where on some ranges it is also a welcome addition as it furnishes excellent spring forage and complements the beauty of native forbs enjoyed as wild flowers.) The withered corollas in this stand of wild oats are California poppy (Eschscholzia californica), State Flower of the Golden State. Wildcat Canyon, Alameda County, California. May. FRES No. 42 (Annual Grassland Ecosystem), no Kuchler units for non-native vegetation, SRM 215 (Valley Grassland). Annual Disclimax Series of Brown et al. (1998).
16. Stand of wild oats at soft dough stage- These wild oat panicles have their spikelets well-filled and the caryopses are appproaching maturity. As was the case for the ripgut presented immediately above, these examples of the naturalized Eurasian (specifically, Mediterranean) annual grass grew in Texas and not in California's Mediterranean climate. Such was another illustration that comparatively mild and moist winters in different kinds of climate (continental vs. Mediterranean) support similar species of plants, especially when facilitated by man as an agent of dispersal. Recall again, the coeval historic development of ranching industries-- and introduction of Mediterranean plant species-- in Texas and California (as well as the coeval development of the two republics and, later, states themselves). Adult plants of the naturalized Mediterranean species as a general rule do not reach as large a size in Texas as in California's Mediterranean climate.
Taxonomy of Avena is one of those that is complicated with taxa being treated differently by different agrostologists. The wild oat in Texas is now understood to be a variety of the domestic oat (A. fatua var. fatua vs. A. fatua var. sativa, respectively).
It was interesting to observe that the oat panicles were of the asymmetrical or unilateral "horse mane" type (branches mostly come off of one side of the rachis) in contrast to the symmetrical or equilateral "tree" type.
Erath County, Texas. April.
"Mane" type of inflorescence of wild oats- Closer and more specific view of the "horse mane" type of inflorescence of wild oats (A. fatua var. fatua). Erath County, Texas. Early May.
Out of the boot- Panicles of wild oats emerging from the boot, the sheath of the uppermost leaf (the flag leaf) that encloses for a time the grass inflorescence. Flag leaf is often the designation once the flower cluster has emerged from the encasing sheath. Boot stage is the stage of phenology or point of growth development when the inflorescence is still down inside the boot. In these two photographs, panicles of wild oats were shown in different degrees of emergence from the boot.
Erath County, Texas. Early May.
17. Spikelets of wild oats at anthesis- Members of the Aveneae (oat tribe) have glumes that are larger than the lemma and that remain on the panicle inflorescence after the grains shatter (ie. persistent glumes). Erath County, Texas. April.
Wild and hairy- Spikelets of wild oats on a panicle at grain-ripe stage of development. Note the considerably greater size of glumes relative to lemma and palea, a characteristic of the oat tirbe, Aveneae. The pronounced pilose pubescence on lemmas is a key feature of Avena fatua var. fatua(discussed more in next caption).
Erath County, Texas. Late April, grain-shatter phenological stage.
Sowing wild oats- Widl oats spikelets shown as: two spikelets, each with two florets, of wild oats (first slide), two spikelets with florets either removed or separated out of glumes (second slide), and two florets with caryopses still inside of hulls, the lemma and plea (third slide).
Pilose pubescence on lemma is a key feature of this wild form (variety) of Aven fatua var. fatua. The geniculate awn of the lemma (visible in all photographs) is another readily seen diagnostic feature of this variety. (Gould, 1975, p. 133) specified that it is the lemma's geniculate (sharply bent or turned) awn that is the feature that separates wild oat (A. fatua var. fatua) from common or tame oat (A. fatua var. sativa), but he also stated the there were three to four florests having stiff, reddish-brown pubescence per speikelet in A. fatua var. sativa whereas there were typically only two florets with glabrous lemmas per spikelet in A. fatua var. sativa. By features given by Gould (1975, 133) spikelets presented here had features of both varieties of Aven fatua though those of A. fatua var. fatua predominated (two to one). Diggs et al. (1999, p.1244) broke with Gould (1975, p. 133) and separated these two taxonomic varieties at species level as A. fatua and A. sativa but apparently followed Gould (1975, p. 133) and stated that A. fatua spikelets were "usually 3-4 flowered (Diggs et al., 1999, p. 1244). Both of these newer authorities were consistent with Hitchcock and Chase (1951, p. 300) who also used "2-flowered" vs. "3-flowered" for A. sativa and A. fatua, respectively. Barkworth et al. (2007, ps. 735-736) described spikelets of the taxon they recognized as species A. fatua (vs. A. sativa) as having spikelets "with 2(3) florets" as well as showing two florets per spikelet in line drawings of this species. This treatment by Barkworth et al. (2007, ps. 735-736) was the specific treatment most consistent with spikelets shown here which were typical of those growing in northcentral Texas.
Erath County, Texas. Late April, grain shatter.,
18. Panicle of soft chess or soft brome (Bromus mollis)- This naturalized Mediterranean annual brome is one of the more palatable species in California anual grassland and annual grass-oak woodland. Soft chess is usuallly regarded as a decreaser, but on more favorable range sites where ripgut brome and wild oats are potential dominants of the disclannual grassland soft chess responds more like an increaser.
Relatively high yield of palatable forage that is free of mechanically injurious awns and calluses make soft brome one of the more desirable of the naturalized Eurasian annual grasses. The Soil Conservation Service Plant Materials Center, Pleasanton, California and University of California cooperatively released Blando soft chess. Certified seed of this accession is available. This is one of the best-- if not the best-- species of Mediterranean annual grass species for reseeding on California annual ranges.
Like many of the Mediterranean grasses, soft chess naturalized up and down the Coast Ranges including those portions dominated by naturalized perennial grasses. Bewnton County, Oregon. June.
19. Stand of hare barley (Hordeum leporinum)- Hare barley is yet another Eurasian annual grass that naturalized in California's Mediterranean climate to become a common, even locally important, species on California annual range, both annual grassland and grass-oak woodland. It is a general--though apparently unpublished observation--that this species has some of the widest leaves and highest relative ratio of leaf to culm of any of the naturalized annual species on the California annual type. Hare barley does not seem to have a consistent respnse to grazing management, however, as do many of the other grass species comprising California annual range.
Numerous studies (see Rosiere [1987] for review or earlier trials as well as original findings) showed variable responses of hare barley to defoliation, including stocking rate. A consensus of grazing trials is that typically hare barley is one of the least sensitive of annual grass species to grazing intensity (only annual fescues are less responsive). Rosiere (1987, ps. 160, 163) reported that hare barley tended to increase with successively heavier grazing (higher stocking rates) though variably so. Over course of this five-year stocking rate trial with sheep, hare barley appeared to be one of the least palatable and least grazed grass species (Rosiere, unpublished observation). Increases of hare barley with heavier degrees of use would thus seem to be more a function of grazing avoidance (by sheep) than of tolerance to defoliation.
The specimens presented here and in the next two slides (immediately below) were growing on fairly deep, fertile soil in northcentral Texas on an area that had been mechanically denuded immediately before the cool-growing season. Erath County, Texas. April.
20. Sexual shoots and spikes of hare barley- Closer focal distance-photographs of plants in the stand of hare barley introduced in the preceding photograph. Another Mediterranean species of annual grass that naturalized to become a component of California annual range, including.annual grassland and grass-oak woodland. Like the situation with the other naturalized Eurasian grasses and forbs, hare barley was inadvertently (apparently) introduced by the earliest Spanish explorers and went on to become a permanent member of the anthropogenic vegetation that permanently (at least in human time scale) displaced and replaced the potential natural vegetation of perennial native bunchgrasses.
Erath County, Texas. April.
Historical and ecololgical note: It should be emphasized that photographs of hare barley along with those of numerous of the other species presented eg. (wild oats, ripgut brome, black mustard, redstem filaree) here were photographed on range in northcentral Texas rather than in California. This was a matter of logistical convenience because the author-photographer had moved from California to Texas when many of these slides were taken. This coincidence served as basis for a lesson in geographic distribution, migration, and species niche of plants as well as lessons in history of the North Amereican frontier and the profession of Range Management.
Introduction of annual grass and forb species from the Mediterranean Region, Spain in particular, to Texas and California was a direct result of establishment by Europeans of livestock (all major species including cattle, sheep, goats, horses, asses, and swine) industries. The earliest of these operations (even of hogs) were range-based ranchos established by the Catholic Church in New Spain. Interested readers can find the thrilling sagas in numerous classic works including such outstanding sources as Towne and Wentworth (1945), Wentworth (1948), Burcham (1957), Lehmann (1969), Myres (1969), Carlson (1982), and Jordan (1993) that were more specific for these two range states that were once republics unto themselves.
The first lesson in regard many of the same Mediterranean annual grasses and forbs in Texas, even north Texas, and California is that they shared a common introduction through Spanish conquest and exploration (initially) and then (later) establisment of a ranching industry in these parts of New Spain. The second lesson was that the Mediterranean climate (Cs in the Koeppen classifiction system) of much of the California Central Valley and Coast Range is similar to that of the Mediterranean Region for which it was named in Koeppen classification. It was a "natural outcome" that annual species introduced from Spain would quickly naturalize in those parts of California with Mediterranean climate.
By contrast, Texas (in particular north Texas) has continental climate (Df in Koeppen classification) such that it was less of a "natural result" that Mediterranean annuals would become naturalized in this more interior area. That these Eurasian species of grasses and forbs did naturalize in Texas and even southern Oklahoma is apparently due to the relatively mild winters that are usually characterized by moderate temperatures and moist soil conditions. This climatic regime is reflected in production of cool-season native grasses including both annual species like little barley (Hordeum pusillum) and sixweeks fescue (Festuca octoflora= Vulpia octoflora) and perennials, the dominant of which is Texas wintergrass (Stipa leucotricha).
21. Redstem filaree or alfilerillo or stroksbill- This Eurasian annual forb of the geranium family was inadvertently introduced from the Mediterranean Region during the early days of New Spain when ranching was begun by the Catholic Church. Redstem filaree is one of the most valuable (if not the most valuable) species of forbs on California annual grassland where it is eaten by all grazing animals, especially sheep and deer (Stubbendieck et al. 1992). The ranker-growing broadleaf filaree (E. botrys) is also a valuable forage plant but less palatable than redstem filaree. These naturalized Mediterranean species are also important on sheep and goat range in the Edwards Plateau and even Cross Timbers of Texas. The native Texas filaree (E. texanum) grows from Texas across to southern California.
22. Flowers and fruit of redstem filaree- Both slides taken in Erath County, Texas. First of these two slides was taken in January while the second was in April. These two photographs give an indication as to possible length of flowering period of this naturalized, annual Eurasian forb (at least in winters of northcentral Texas).
23. Fruit of redstem filaree- Close-up of friut of Erodium cicutarium at mid-maturity stage. Erath County, Texas. April.
24. Stand of black mustard (Brassica nigra)- This dense stand of black mustard was growing on an open area in California annual grass-oak woodland or, perhaps more specifically, a glade of annual grassland within the California blue oak woodland. This population of black mustard was apparently typical of those throught which California vaqueros chased the scrub California variety of Spanish Longhorns in pursuit of hides and tallow during what is still known as "California's Golden Age". The Eurasian naturalized black mustard must be readily eaten by livestock because big stands like this are seldom found on ranges other than those lightly grazed. Black mustard is most common on areas protected from grazing. Dayton (1966, ps. 3-5) described black mustard as "fairly palatable ... to both sheep and cattle" with sheep even bloating from consumption of large quantities of it.
In the past this annual crucifer was often a pest over large areas of farm land, but effective herbicides have changed much of that. Where weed control and heavy grazing are absent plants of this species, which is the main source of food mustard, can still be found in great concentrations like that shown in this photograph.
Butte County, California. June.
25. Black mustard- Four plants of the naturalized annual black mustard growing on a disturbed area of California annual rangeland that was protected from livestock grazing and mowing. This Eurasian drug crop reverted back to the wild type and naturalized over much of California's annual grassland and annual grass-oak woodland by the 1830s (Burcham, 1957, p. 123) which was within six decades of the development of livestock ranching in the California portion of New Spain.
These plants were still in the winter rosette stage of phenology even into late spring. As black mustard age and grow the leaves elongate forming large spaces along their margins (compare these rosette leaves with those of mature plants in the two preceding photographs).
Butte County, California. June.
26. California poppy (Eschscholzia californica)- This member of the poppy family (Papaveraceae) is in the genus known as goldpoppy. According to Dayton (1960. ps. 212-213) this is an extremely variable species in it's different taxonomic forms. Even the life cycle of this State Flower of California varies from annual to short-lived perennial. Dayton (1960, p. 212) stated that E. californica has naturalized throughout the western range region as a consequence of propagation of the species as an ornamental. That phenomenon was reflected in these photographs: that of the whole plant was taken in Utah County, Utah while the flowers and fruits were on a plant growing in Idaho County, Idaho (both photographs taken in June).
27. Serpentine
Barrens Rock outcrop- An extremely harsh edaphic environment created
by the presence of the mineral serpentine is one of the more common
forms of barrens along the Pacific Coast. When serpentine barrens is
combined with rock outcrop, one of the most common forms of barrens
continent-wide, the habitat is definitely BAD.
Serpentine forms a unique, if harsh, habitat and, following an initial
period of mostly being ignored by ecologists, serpentine sites became
a “pet” subject of study in the Pacific Region. Readers
are first referred to the relatively recent reviews by Kruckeberg (1984),
Kruckeberg in Anderson et al. (1999, ps. 309-321), Tyndall and Hull
in Anderson et al. (1999. Ps. 67-82), and Kruckeberg (2006). The older
work, some of it classic, was given in the references of these recent
reviews.
Serpentine is a mineral conisisting basically of a variable hydrous
magnesium silicate, a complex magnesium-rich silicate— chiefly
as Mg3Si2O5(OH)4 —in
fine waxy masses (but locally fibrous as asbestos), having colors ranging
from dull or light green to dark green to black with intermediate brownish-red
or yellow and often with a mottled appearance. Serpentine formed by
alteration of peridotite (olivine) in presence of water and thus can
occur in or as rock, both altered peridotite and pyroxenites. Serpentine
is one of the ultramafic rocks (igneous rocks composed mostly of mafic
minerals which are dark-colored iron-magnesian rock-forming silicates
with olivine, chromite, and pyroxene as major minerals).
Serpentine parent material weathers into soils rich in magnesium, iron, nickel, and silicates. Serpentine soils have montmorillonite as the common clay mineral. Serpentine soils include both alluvial and upland series. The upland serpentine soils are azonal soils that are stony, shallow, and lack regular profile development. In addition, serpentine soils have high levels of exchangeable magnesium and exrtremely low levels of exchangeable calicum. They are typically deficient in nitrogen and phosphorus among macrominerals and molybdenum among trace elements while containing hyper-levels of the heavy metals iron and nickel. This creates a “serpentine syndrome” of infertile soils combined with toxicity of magnesium and heavy metals (Kruckeberg, 1984, ps. xii, 6-8, 18-26). In short, not the place for a plant to plan on having a party.
Yet, certain plants survive, if not thrive, here. Some of them are serpentine endemics. Others have distribution patterns varying between serpentine and non-serpentine soils while yet others are categorized as indifferent (= bodenvag= ubiquist) species and occur on and off serpentine soils with no apparent taxonomic differences within species on both categories of soil (but ecotypic variation cannot be ruled out definitely). See Kruckeberg (1984, ps. 34-44) for discussion of plant species relations on serpentine soils.
Response of range animals to serpentine sites and vegetation thereon has received much less study than has the more basic plant respones.
The Serpentine Barrens Rock Outcrop Site seen here is dominated by big squirreltail (Sitanion jubatum) which is one of the indifferent or bodenvag serpentine species. This is a very restricted site (microsite) in the northern Coast Range. The surrounding oak woodland on either side and the California annual grassland behind are not on serpentine soils. Foster Pasture, University of California Hopland Field Station, Mendocino County, California. Late May, nearing end of growing season.
Serpentine Barrens were too small to be mapped at the scale used by Kuchler (1966, 1977), but this local site is obviously an "island" of the California bunchgrass prairie (K-41, California Steppe). As discussed earlier, SRM failed to designate and describe California steppe or Pacific bunchgrass prairie.
28. Serpentine Barrens range site of California annual grassland- Kruckeberg (1984, p. 41) listed a number of Eurasian annual grasses which he felt must be indifferent (= bodenvaq or ubiquist) species on serpentine and non-serpentine sites. He listed wild oats, soft brome, red brome, nitgrass (Gastridium ventricosum), and foxtail fescue (Festuca megalura). All of these species except wild oats are common on the parcel of naturalized annual grassland in this photograph. There is a relatively higher proportion of lower-seral stage species in this community with soft chess (= soft brome) being the only species that sometimes responds as a naturalized decreaser. Almost all of the grasses seen here are naturalized invaders like red brome, nitgrass, and foxtail fescue. Rosiere et al. (1986) studied the range plant community and domestic sheep diets on this same pasture and compared them to those from non-serpentine range sites on this same ranch. They found that there were few real differences in diets and the main difference in range species compostion was a lower proportion of decreaser and increaser grasses on the Serpentine Barrens.
Foster Pasture, University of California Hopland Field Station, Mendocino County, California. Late May. FRES No. 42 (Annual Grasslands Ecosystem), Kuchler (1966, 1977) did not map naturalized vegetation. Serpentine sites on California annual grassland were included under SRM 215 (Valley Grassland). Variant of Annual Disclimax Series of Brown et al. (1998).
29.
Serpentine Barrens soil- The soil series of the Serpentine Barrens range
site just seen is Montara, a Vertisol. Cracking of this azonal soil
is due to it's high shrink-swell potential resulting from the
high content of montmorillonitic clay (mentioned above) and the shallowness
of this upland soil. The physical features of cracking and shallowness
together with chemical infertility creates a harsh edaphic habitat for
range plants. What is so interesting, however, is that the annual grass
species are the same on the Serpentine Barrens as on the non-serpentine
site except there are higher proportions of the less palatable species,
especially naturalized invaders, on the Barrens. This is because on
this range sheep are attracted to and spend more time grazing and, generally,
congregating on the Serpentine Barrens sites. The actual reason why
sheep preferred grazing and loafing/resting on the barrens was not determined
when Rosiere et al. (1986) compared sheep diets from the barrens to
diets from non-serpentine sites. Note that even under the relatively
heavy degree of use on this site soft chess still set seed for next
year.
Foster Pasture, University of California Hopland Field Station, Mendocino
County, California. Late May. FRES No. 42 (Annual Grasslands Ecosystem),
no Kuchler designation. SRM 215 (Valley Grassland). Variant of Annual
Disclimax Series of Brown et al. (1998).
30. Comparison of grazed and non-grazed vegetation on a Serpentine Barrens range site- On the left is the grazed Serpentine Barrens range seen in the previous slides. On the right is a 25 year-old exclosure. Naturalized Mediterranean annual grasses dominate grassland communities on both sides of the fence, but there are more individual plants of the native perennial bunchgrass species in the 25-year exclosure (none could be found on the grazed portion). California melic (Melica californica) and purple needlegrass can be seen in the exclosure. Rosiere et al. (1986) concluded that the range vegetation on Serpentine Barrens was not strictly determined by edaphic conditions and features but that it was a combination edaphic-zootic climax. All California annual grassland is disclimax but on serpentine sites the role of grazing appeared even greater. In fact, it seemed (based strictly on personal observation and judgment) that the native bunchgrasses were more common on serpentine than on non-serpentine soils. This is not to say that the native climax grasses would recover and recreate the pre-white man Pacific prairie on serpentine soils if protected from grazing. It does suggest that the native perennial grasses are comparatively better adapted to and more competitive with Mediterranean annual grasses on serpentine sites. Natives like needlegrass, melicgrass, and squirreltail are frequently much more abundant in exclosures on serpentine soils than in exclosures on non-serpentine soils. This is an example of how interactions of management factors (eg. stocking rate, animal distribution) and plant growing conditions influence range vegetation.
Note how perennials extend the green feed season. The annual species have been brown for three weeks and the native bunchgrasses are "still green". On Hopland Field Station the author observed purple needlegrass that retained green shoots through June even on south slopes and through most of July on north and east slopes.
Foster Pasture, University of California Hopland Field Station, Mendocino County, California. FRES No. 42 (Annual Grasslands Ecosystem), SRM 215 (Valley Grassland). Variant of Annual Disclimax Series of Brown et al. (1998).
An admittedly too-short treatment of the perennial grass-dominated prairie that developed along the immediate Pacific Coast was included here. As with the once more widespread interior California prairie, almost all but a few infinitesimally small, pristine relicts of coastal prairie vegetation was highly disturbed and radically changed (some individual ranges and tracts more than others). A few examples of this grassland range vegetation were presented below.
31. Coastal California prairie- Virgin Idaho fescue Pacific Prairie on Angel Island California. SRM 214 (Coastal Prairie). Mixed Bunchgrass Series in Oregonian (Pacific Coastal) Grassland biotic community of Brown et al. (1998).
The original (climax; pre-Columbian) bunchgrass California or Pacific Prairie was grassland dominated by perennial cespitose festucoid grasses. Traditionally it was interpreted as the western extension of the bunchgrass prairie whose eastern form is the Palouse Prairie, the pattern of winter precipitation being the unifying factor. The Pacific Slope or California Prairie has the mild winter temperature regime of its Mediterranean climate. The California bunchgrass prairie consist of two forms, units, or subdivisions:
1) the more extensive purple, nodding, and foothill needlegrass (Stipa lepida) grassland (Stipa prairie) of the Great Central Valley (Sacramento and San Joaquin Valleys), Coast Range, and Sierra Nevada foothills that was just discussed and
2) the California Coastal or North Coastal Prairie (Festuca-Danthonia grassland) that even in pre-European times was restricted largely to isolated pockets around San Francisco Bay and Cape Mendocino.
Dodd in Gould (1968, ps. 334-335) interpreted the California Prairie as a Clementsian association with these two main forms as "“communities". He based his short descriptions largely on the seminal history of California range by Burcham (1957). Dodd listed original dominant species of the North Coast Bunchgrass Prairie as California oatgrass, tufted hairgrass, western fescue (Festuca occidentalis), Idaho fescue, and Pacific reedgrass (Calamagrostis nutkaensis).. Heady et al. in Barbour and Major (1995, ps. 733-745) listed dominants of the Coastal California Prairie as Idaho fescue, red fescue (Festuca rubra), and California oatgrass with tufted hairgrass, Pacific reedgrass, and Junegrass among associated species.
The climax Coastal Fescue-Oatgrass Prairie was a unique but minor unit of California Prairie and now exist only as scattered relict remnants of what in virgin conditions was a tiny range type as North American grasslands go. It is of no agricultural production significance but the relict parcels are wisely preserved for scientific and aesthetic value of native species and vegetation. Minor form of FRES No. 36 (Mountain Grassland Ecosystem) because this grassland ecosystem includes K-40 (Fescue-Oatgrass).
SRM 214: as discussed regarding climax needlegrass prairie, the pre-Columbian California grasslands were inadvertently destroyed and simultaneously converted by human action into a disclimax (anthropogenic climax) grassland which is now the range type sustained under proper range management. The man-made— and completely naturalized —grasslands are those correctly designated and described as rangeland cover types. Nonetheless, and as explained under the climax needlegrass prairie, the original pre-European grasslands— both needlegrass and fescue-oatgrass prairies — still exist as scattered relicts and merit SRM rangeland cover type designation and description. They are range— native range —and they are important historically and to those concerned with natural ecosystems and vegetation.
Sawyer and Keeler-Wolf (1995) identified and described series of the North Coast Pacific (California) Prairie based on dominance by single climax species. These included: California oatgrass series, Idaho fescue series, Pacific reedgrass series, and tufted hairgrass series.
California Native Plant Society Idaho fescue series of Pacific Bunchgrass Prairie-Angel Island, San Francisco Bay, California, May (prebloom stage).
"Few places on earth, if any, have had such a rapid wholesale replacement of native plants by introduced species" (Burcham, 1957, p. 185).
32. Coastal California Introduced (Anthoxanthum-Holcus) Grassland- Perhaps California more than any other portion of our planet has had nearly complete conversion of its grasslands from native to domestic (= introduced= agronomic) forage and weed species, accidentally or unintentionally. Deliberate, planned conversion of native grasslands (and forests) to grasslands of tame (domesticated, usually introduced) species has occurred across the globe as man has gained dominion of it. These crop lands (eg. permanent pastures of field crop grasses and legumes) grow on a sizeable portion of Earth's land and furnish essential food and fiber to an overcrowded, if not overpopulated, planet. In California from the Central Valley, Coast Ranges, Sierra Nevada foothills, to the Pacific beaches native grasslands were changed largely by accident and not design into anthrpogenic grasslands. Here native species were displaced/replaced by Eurasian species of weeds and domesticated forage plants introduced accidentally, and haphazardly by European man. As emphasized repeatedly, these human-induced disturbance climaxes are as matter of practical necessity recognized, studied and managed as naturalized grasslands manipulated for agricultural production (ie. they are naturalized, versus native, range).
By and large, the introduced species that became dominant on California grasslands were not desirable domestic forages but instead weedy or nuisance plants (aletophytes) which by sound range, especially grazing, management can be used conveniently, advantageously, and permanently. These are either: 1) agrestals (plants growing uncultivated, undesirable, and unwanted on agricultural land; weeds in the strict, classic sense) or 2 ) ruderals (plants that pioneer but usually persist but briefly in disturbed or early successional environments). Weediness notwithstanding, the disclimax grasslands provide nutritious feed even if for a much reduced time (due to a shorter green feed season compared to perennials). In fact, Burcham (1957, p. 185) pointed out decades ago that is was common knowledge among rangemen then that when annual grassland is properly managed so as to have decreaser species like wild oats, soft chess, and ripgut brome the nutritive value of forage may exceed that of the native perennials.
This is not the case for the anthropogenic naturalized coastal prairie. Ironically the species that took over the fescue-oatgrass prairie were cultivated European grasses (not weeds as in case of annual grassland) purposely introduced for range improvement, specifically to revegetate ranges depleted by overgrazing, improper burning, weed introduction, etc. (Burcham, 1957, p. 201). Unfortunately the more desirable tame pasture species like orchardgrass and timothy did not "take hold". Instead common velvetgrass (Holcus lanatus) and sweet vernalgrass (Anthoxanthum odoratum) became dominant (Barbour and Manor, 1995, ps. 734-745). These grazing tolerant perennials are of low forage value (Hitchcock and Chase, 1951; Sampson et al., 1951; Crampton, 1974) so that the vernalgrass-velvetgrass grazing disclimax of the North coast California Prairie is inferior to the original fescue-oatgrass climax.
33. Sward of naturalized Coastal California Prairie dominated by common velvetgrass and sweet vernalgrass- Associate species include annual alien big quaking grass (Briza maxima) along with smaller amounts of perennial natives tufted hairgrass, Pacific reedgrass, and California oatgrass. Replacement of native perennials has not been as complete as in the California annual type. Both photographs near West Port Union Landing State Beach, Mendocino County, California. June. Naturalized variant of FRES No. 36 (Mountain Grasslands Ecosystem), K-40, SRM 214 (Coastal Prairie). California Native Plant Society introduced perennial grassland series.
34. California beach dune grassland- European beachgrass (Ammophila arenaria) is a naturalized aggressive, rhizomatous perennial that forms monocultures or consociations (take your choice) which exclude the less competitive native vegetation. The invasive European beachgrass crowds out such natural communities as the native dunegrass, soft wildrye usually known as sea lyme grass (Elymus mollis= E. arenarius var. mollis), on foredunes (shown in Tundra slides) and sand verbena-beach bursage (shown in Shrubland slides). European beachgrass does stabilize— and rapidly —shifting or blowing dunes (why it was introduced). It is now as thoroughly naturalized and as much a grassland range cover type as California annual grassland or introduced coastal grassland. Natural communities like soft wildrye dune grasslands were apparently quite restricted even before arrival of white man in California. This is because most of the California coast is cliffs rather than beaches (Pickart and Sawyer, 1998, p. 1) with less than 25 % of the California coastline being beach and dune (Barbour and Major, 1995, p. 224). Furthermore, as might be expected much of the beach-dune environment has been adversely affected , and highly so, by human inpact. As such, major efforts are underway to preserve what remains. This includes removal of European beachgrass and its replacement with native beach communities. In other locations where natives are less desirable Ammophila is probably beneficial and will likely remain anyway.
No FRES, K-, or SRM designations. In fact, beach communities and estuaries have received little consideration by any regional- or continental- scale vegetation mapping and classification systems. California Native Plant Society European beachgrass series.
The various dune communities exist coastward of the coastal grassland and coastal scrub communities, but these often form a mosaic or patchwork of interspersed communities. The Pacific Coast supports a complex vegetation and diverse flora, and with an array of different kinds of forest adjacent to them. Any arrangement of range cover types based on biomes is, while not arbitrary, quite artificial. Scrub communities adjacent to coastal grasslands are included in the Shrubland slides.
Sea lyme grass or ashy (= soft) wildrye, the native dune stabilizer, was shown by Kuchler (1977) in his map of potential natural vegetation California as part of the Northern Seashore Community (unit number 50). This localized consociation occurs northward along the shores of Alaska. An example of this grassland cover type was included in the Tundra slide set because that is where the photograph of that vegetation was taken.
35. Inflorescence of European beachgrass- Both slides taken at Ten Mile Coast Relict Area, Mendocino County, California, June.
36. California Coastal (Humboldt Bay) Salt Marsh- As with beach and dune vegetation, that of the zone encompassing estuaries, tidal flats, and fresh backwaters is a vegetational complex that defies "tidy" classification and description. And as with most California grasslands, the marshes have been variously and permanently (in human time scale) changed from climax (native or natural) composition and structure. "Reconstruction of the crime" and hence of original structure even on paper, not to mention on land, is improbable.
Shown here is a coastal salt marsh at reach of high tide (most saline) existing as a consociation of dense-flower cordgrass (Spartina densiflora), a species you may have guessed by now that is an alien introduced, this time, from the New World. It arrived in California in the ballast of lumber ships from Chile (Barrbour et al. 1993, p. 42). In many other California coastal marshes the dominant grass is the native species, California cordgrass (S. foliosa), especially as a colonizer of tidal mudflats. Major associates visible here are sea arrowgrass (Triglochin maritimum) and coast saltgrass (Distichlis spicata). Arcata Marsh, Humboldt County, California, June. FRES No. 41 (Wet Grasslands Ecosystem), K-65 (Northern Cordgrass Prairie), SRM 217 (Wetlands), Pacific Coast saltwater marsh varient. Cordgrass Series in California Maritime Marshland biotic community of Brown et al. (1998).
37. Sward and physiogonomy of Northern California Coastal Salt Marsh- Dense-flower and coast saltgrass dominate a mudflat that formed over an abandoned log pond. The conspicuous (and major) forb is marsh gumweed (Grindelia strieta). Pickleweed (Salicornia virginica) occurs bayward from this point. Arcata Marsh, Humboldt County, California, June. FRES No. 41 (Wet Graslands Ecosystem), K-65 (Northern Cordgrass Prairie), SRM 217 (Wetlands), the Pacific Coast saltwater marsh varient. Cordgrass Series in California Maritime Marshland biotic community of Brown et al. (1998).
38. Northern California (Humboldt Bay) Coastal Salt Marsh showing a consociation of dense-flower cordgrass with coast saltgrass, and sea arrowgrass occupying spaces between tufts of cordgrass. Occasional plants of alkali sacaton and rare individuals of beardless wildrye (Elymus triticoides) are also present. Arcata Marsh (bayward of freshwater marsh), Humboldt County, California, June. Cordgrass Series in California Maritime Marshland biotic community of Brown et al. (1998).
39. Dense-flower cordgrass- Humboldt County, California, June.
40. Coastal (Pacific Coast) freshwater marsh- A "tule pond" dominated by common or giant tule or bul(l)rush (Scirpus acutus) and broad-leaf cattail (Typha latifolia). Yellowing grass in foreground is water foxtail (Alopecurus geniculatus). Small tree on far left is California wax myrtle (Myrica californica). Portion of Butcher Slough, Arcata Marsh, Humboldt County, California. June. FRES No. 41 (Wet Grasslands Ecosystsem), K-42 (Tule Marshes), SRM 217 (Wetlands), California Native Plant Society bulrush-tule series.
This is only one of many kinds or communities of freshwater marshes found throughout North America. Each different community is unique in it's species composition. There are both coastal and inland (including montane) freshwater marshes just as there are coastal and inland salt or brackish marshes.
41. Inflorescence of common (= giant) tule or bulrush tule.
42. Bay or lagoon saltmarsh (coastal brackish marsh)- This hypersaline habitat is Big Lagoon, Humboldt County, California (June). The simple plant community is made up of narrow-leaf cattail (Typha angustifolia) in foreground and tules (Scirpus spp.) in background. FRES No. 41 (Wet Grasslands Ecosystem), K-42 (Tule Marshes), SRM 217 (Wetlands), California Native Plant Society bulrush-cattail series.
References for coastal marshes of California or the Pacific Coast include chapter 8 of Barbour and Major (1995), Barnhart et al. (1992), Barbour et al. (1993, ps. 41-51), and Peinado et al. (1994). Material on salt marshes of New England are also relevant with Nixon (1982) and Teal (1986) among the best. The popular and easily read classic by Teal and Teal (1969) comes highly recommended. It deals primarily with salt marshes of the Atlantic coast but is applicable to those of the Gulf and Pacific.
The Pacific coastal marshes and/or grasslands join either the Pacific forest in any of it's various cover types (eg. Sitka Spruce, Redwood, or Douglas Fir cover types) or the coastal shrublands. In some localities the coastal scrub is between the Pacific and grasslands while in others the grasslands occur most shoreward and the scrub vegetation grows farther inland to butt against the coastal forests.
43. Smooth bromegrass seeding- Smooth or anwless bromegrass (Bromus inermus) is another cool season Eurasian grass introduced into the pastures and ranges of North America. Its introduction pre-dates that of crested wheatgrass and some other non-native species that are managed as range plants. Smooth brome is not as important for "non-native range" as many of these species. Furthermore, most of the vast acreage planted to this productive and nutritious grass is managed agronomically as tame pasture and/or a hay crop. Nonetheless, smooth bromegrass is frequently seeded and managed as an introduced range plant. On more fertile soils smooth brome has potential alternatively as a tame pasture or range grass depending on economic factors ranging from price of fertilizer and availability of labor to value of hay. Smooth brome is extremely useful in reclamation of drastically disturbed land such as stabilization of road cuts and establishment of vegetative cover on mine spoils. Smooth brome has naturalized and become a common species in northern portions of the the Western Range especially as an understory species in forests where it is associated with other introduced European grasses such as timothy and orchardgrass, and domesticated legumes like white clovef (Trifolium repens).
This smooth bromegrass seeding in Harvey Valley, Lassen National Forest, California was used to restore depleted range more efficiently and with less risk of crop failure than if attempting to reestablish native grass species such as bluebunch wheatgrass or Idaho fescue. In such situations smooth brome provides vital vegetative cover faster and more reliably than native species and is superior in reduction of accelerated erosion and protection of critical watersheds. It not only provides nutritious forage for both livestock and wildlife but it can actually increase forage (and total nutrient) yield and, ultimately, animal turn-off. Note that as with crested wheatgrass, native shrubs (eg. the sagebrush growing here) come in on range reseeded to introduced grasses and help form a range plant community in contrast to the monocultures or single-species stands of agronomic pastures. Again, as this is not native (potential natural or climax) vegetation it has neither FRES nor Kuchler unit recognition. No SRM designation either.
44. Close-up of the smooth brome seeding seen in the previous view- This reseeded range has a bunchgrass structure in contrast to the usual sod form when smooth bromegrass is managed as domestic pasture and hay field. Harvey Valley, Calirornia. July, late vernal-early estival aspect.
45. Stand of smooth bromegrass at peak standing crop (just after anthesis)- This old field reseeded to smooth brome is an example of the tremendous herbage yield and soil conservation that is possible with this introduced European tame pasture grass.
46. Panicle of smooth brome. Gallatin County, Montana. June.
47. California annual grassland overseeded to subterranean clover (Trifolium subterraneum)- The disclimax annual grassland thathas permanently replaced the original climax bunchgrass prairie of california's Central Valley, Sierra foothills, and Coast Range can be improved by such agronomic means as fertilization and reseeding to higher-yielding cultivars of the naturalized annual grasses, tame pasture grasses, and legumes. One of the most useful improved legumes is subterranean clover that was introduced from Australia. This fertile alluvial site of annual grassland was overseeded to Mount Barker and Woogenellup cultivars of sub-clover and periodically fertilized. Love and Murphy Pasture, University of California Hopland Field Station, Mendocino County, California. April. FRES No. 42 (Annual Grasslands Ecosystem), no Kuchler unit for annual grassland. Improved variant of SRM 215 (Valley Grassland). Improved variant of Annual Disclimax Series of Brown et al. (1998).
48. Sward of the pasture of improved annual grassland shown in preceding slide- Subterranean clover is co-dominant with soft chess. Associates are wild barley (Hordeum leporinum, H. hystrix) and filaree.
49. Sub-clover-annual grassland sheep range- California annual range overseeded to legumes like subterranean clover is sheep pasture par excellence. Here a typical Targhee ewe and her Suffolk-sired lamb graze the sub clover-annual grassland seen in the last two shoots. Peak standing crop stage. The clover with the co-dominant soft brome and associated wild barley are conspicuous.
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