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North America is the grassland continent. No other major land mass on Earth had such a large proportion of its biomes or plant formations dominated by grasses as did North America prior to modification by human action. Grasslands and/or grassland-savanna mosaics of vegetation probably covered a larger portion of the North American continent than forests, deserts, or any other biome. Likewise, the diversity of botanical composition and physiognomy was greatest here.
"While I know the standard claim is that Yosemite and the like afford the greatest natural shows, I am not so sure but that the Prairies and Plains last longer, fit the aesthetic sense fuller, precede all the rest and make North America's characteristic landscape" -- Walt Whitman
Grassland refers to that biome dominated by grasses, species of the Gramineae (Poaceae). In a broader or more generic or, perhaps, poetic sense "grasslands" has frequently been used to emcompass true natural or native grasslands, marshes, native meadows, and introduced permanent pastures that are swards made up largely of domestic (= agronomic, henced introduced) herbaceous species including important legumes and, though rarely, even composites and crucifers. Examples of all these categories or groups of "grassland" as applied in the generic sense were included under the heading of Grassland in Range Types of North America.Specifics of this introductory statement were given in the following longer explanation.
The term grassland has several different meanings or connotations depending on usage. In the simple literal and general meaning grassland is land on which the vegetation is dominated by grasses. The strict ecological and quite specific definition of grassland is the biome dominanted by grasses as the major plant family (Gramineae) and as the dominant taxa of the predominant plant growth or life form. This results in the physiogonomy of herbaceous vegetation varying at different seasons for the same plant community and over space and sites for the many kinds of grass-dominated communities (even with all these at climax). On several types or associations of the grassland biome there are fewer species of the Gramineae than of the Compositae or even of the Leguminosae, but grasses are the dominant taxonomic group of plants from standpoint of biomass and productivity, cover, density, and overall impact on the biotic community as well as importance in soil formation and moderation of climate and weather. For example, on tallgrass prairie there are far more species of forbs (including pteridophytes like ferns and horsetails) than of grasses and grasslike plants combined. Yet grasses are the dominant, associate, and major indicator species and exert are far and away the critical and major coactions (biological influences) on the natural vegetation, usually even in most seral stages.
"Grassland" in a generic or poetic usage refers to land dominated by or, sometimes, supporting exclusively herbaceous vegetation often with the connotation that the herbage of this vegetation is feed (forage) for grazing animals. In the latter instance "grassland" has often been used to refer to land, vegetation, or even a monoculture of forage on which grasses are limited or even absent. The most common non-grass forages on "grassland" as used in this generic sense are, of course, legumes. In this context the Iowa State text, Forages, has defined grassland as: "Land on which grasses and/or legumes constitute the dominant vegetation". Technically speaking, again in a strict meaning from the view of Vegetation Science, that definition is incorrect, or at very least, ambigious because plants of a single species (or perhaps even of two species) growing in a field comprise a population and not a community or vegetation.
"Grassland" in this generic sense has assumptions that are generally understood and accepted by those "in the know" much like for the generic "man", "gentlemen", "dogs", "cows", and "cattle". For instance, in Western Range parlance "cows" has the literal meaning of a female of the Bos species that has had at least one calf. But range usage (in fact, general farm usage in many areas) of "cows" can also be as a synonym for "cattle" to refer to all bovines including new-born calves, bulls, steers, heifers, as well as the literal meaning of a female Bos that has borne offspring. "Cattle" in the Middle English usage (eg. King James Version of the Holy Bible) was a synonym for all livestock (horses, hogs, goats, etc. as well as Bos species, this latter group distinguished from the generic group by being specified as "black cattle"). "Cattle" as defined in the American market class refers to bovines larger than calves, hence "cattle and calves" such that calves are not cattle.
So it goes. Lesson for neophytes. Initiates must master meanings of terms used in the trades and professions that are conditional and situation-dependent. The simple instruction of the cow boss to "Bring all the cows" can mean two different things to the cow hands depending on the situation. Much additional work, not to mention embarrassment and lost respect, will incur unless the response is to the precise meaning. Sometimes meaning of the same term even varies with tone or inflection of voice as well as situation. One of the most common examples universally used by ranchmen (another generic and democratic term) is the clipped Shakespearean (King Lear) "son of a bitch" which can have any one of at least a half-dozen meanings depending on context. The first step in learning basic concepts in any "course" is to master terms and their meanings.The generic term "grassland" as herbaceous crops or vegetation available for use as forage is the meaning employed in the old concept for and the kind of agricultural production system known as grassland agriculuture.
Grassland Agriculture- "A system of agriculture in which a major emphasis is placed on grasses, legumes, and other fodder or soil-building crops. The system may be extensive, as in many natural grassland or desert shrub areas, or it may be extremely intensive. The sod crops may be permanent or simply a part of a rotation. The principal feature of grassland agriculture is the dependence of the system on grass crops for soil building and animal nutrition. Grassland agriculture, is therefore, a dynamic system in which the soil, the plant, and the animal are intimately and inseparably interlocked" (Harlan, 1956, p.vii).
Grassland Agriculture- "Farming system that emphasizes the importance of grasses and legumes in livestock and land management" (Hughes and numerous other authors, 1962, 1973, 1985, 1995).
Grassland Agriculture- "A land management system emphasizing cultivated forage crops, pasture, and range for livestock [and wildlife] production and soil stability" [added]. (Vallentine, 1990).
The intimate association of grassland agriculture with the fields of Agronomy, Range Management, Animal Science, Agricultural Economics, and Forestry (for starters) and its pivotal role in integration of these disciplines, and the agricultural systems therein, necessitated inclusion of agronomic (= domestic, introduced, "tame") forage species in the Grasslands section. This included legumes. It included some grasses and legumes that are used more as harvested forages, especially hay, than as grazed forages. Priority was given to introduced (agronomic) species that are common in range regions and that are crops integral to Range Management and ranching operations. Priority was accorded those introduced species that have naturalized (meaning they are self-propagating and do not require replanting, or at least for extended periods of time as measured on human scale) and that can, under certain conditions and agricultural practices, be managed extensively (ie. as if they were native or indigenous). Cultigens (species or cultivars that are completely dependent on domestication and cannot persist other than for one or a few growing seasons without renewed human propagation) and adventives (accidentally planted cultigens that exist for one season) were excluded. A good example of a perennial grass in this group-- even though it is widely used as permanent pasture-- is the sterile hybrid cultivar Coastal bermudagrass (Cynodon dactylon cv. Coastal).
Also included under the category or grouping of introduced forages were species native to North America (ie. range plants) that were or are being domesticated. The most notable examples of this category are native, warm-season, perennial prairie grasses that are in the process of being domesticated or, at least, semi-domesticated for use as field (= agronomic) forage crops in some areas. In other words, species in this group are in the reverse role or situation of "tame" (domestic) species that are used as if they were native. Here native range grasses have been or are being domesticated and used under management that is more intensive than under "natural conditions" (ie. husbandry that is either Agronomy or closer to Aronomy than to Range Management). Instead of introduced forage species managed so as to revert (to some degree) to the "wild", "wild" (native) forage species (ie. range plants) are managed more intensively so as to become domesticated forages (ie. field crops). Various cultivars and accessions of Eastern gamagrass (Tripsacum dactyloides) make up one such example.
Permanent pastures included as rangeland cover types (eg. tall fescue which is SRM rangeland cover type 804) conformed to the guidelines given by Vallentine (1990, p. 10). Permanent pastures are medium-term grazing lands and share this classification category with transitory forest range such as pine plantations, burnt and cut-over timber lands, and go-back land (old-fields). This inclusion of agronomic species to allow for overlap of Agronomy and Range Management (agronomic vs. more ecological management; intensive vs. extensive inputs) is consistent with the interface of Forestry and Range Management by inclusion of forests that are range only as and during a state of transition to closed canopy forest.
Marshes are those wetlands dominated by herbaceous vegetation—primarily grasses, sedges, rushes, cat-tails, etc.—growing in soils more or less permanently waterlogged or at state of saturation (ie. soils with water above field capacity most of the time). Vegetation growing on land covered with water permanently not periodically. Vegetation is climax at climatic time-scale; it is the potential natural wetland vegetation that is in dynamic equilibrium with the determinative factor(s) of habitat be it climate, soils, fire, flood, etc.
Marshes have traditionally been divided into two or three categories based on salinity of water:
1. Freshwater Marsh,
2. Saltwater Marsh and, sometimes,
3. Brackish Marsh (for those with mixing of upstream fresh water with saline water from oceans, salt lakes, etc.
These categories or general kinds of marshes include several distinctive wetlands with such freshwater marshes as everglades, tule marshes, and borders of oxbow lakes and such saltwater marshes as smooth cordgrass all along the Gulf and Atlantic Coasts or tidal marshes in bays.
Meadows shown as range cover types are those that conform with definition (2) of the Society for Range Management (Kothmann, 1974; Jacoby, 1989): "Openings in forests and grasslands of exceptional productivity in arid regions, usually resulting from high water of the soil, as in stream-side situations and areas having a perched water table".
These native meadows (which often include introduced species that have naturalized) are of two types:
1. Wet Meadow- "A meadow where the surface remains wet or moist throughout the summer, usually characterized by sedges and rushes [less commonly by hydrophytic grass species]" and
2. Dry Meadow- "A meadow dominated by grasses [less commonly by sedges or other grasslike plants adapted to less mesic or hydric conditions] which is characterized by soils which become moderately dry by mid-summer (Kothmann, 1974; Jacoby, 1989 as [amended by Rosiere herein])".
Meadows are defined as more or less natural (comprised of native species) kinds of vegetation (or biotic communities if animals included) or ecosystems irrespective of the use made of them. In other words, as used herein meadows are like grasslands, deserts, forests, tundra, etc. They are biomes (of admittedly small spatial scale) delimited by the predominant growth or life form of vegetation. Meadows, grasslands, savannas, etc. are not —as is range by contrast— a kind of land based on it’s use (eg. any vegetation is by definition range only when it is subject to grazing or browsing). Meadows are meadows whether or not they are grazed or mowed for hay. Meadows become range (rangeland cover types) when used for grazing (or mowing). SRM definition (1) of meadow specified a primary use "for hay production" (ie. hay meadows). Many meadows represented by the vegetation displayed herein do qualify under both definitions, but it is only definition (2) that is applicable as basis of natural vegetation. Otherwise tallgrass prairies used for production of prairie hay "which are hay meadows only" would be meadows. This would be misleading because hay meadows are meadows only by criteria of definition (1) (eg. bluestem prairies can only be hay meadows and they should not be confused with meadows based on soil water criteria).
Marshes are some of the most valuable of all wetlands. They are also some of the productive (both ecologically as in Net Primary Productivity and agriculturally as in biomass production for hay, natural pasture, and wildlife habitat). This is especially so for waterfowl (ducks, geese, cranes, herons, plovers, swans, etc.). They are also important breeding grounds for fisheries, including as oyster beds. Marshes include wet meadows (there is not always a clear distinction between wet and dry meadows as some are intermittent or ephemeral wet meadows, especially subalpine mountain meadows). Inland wet meadows on floodplains are one extremely important sources of hay for beef cattle in the Intermountain Region. With careful and conscientious management such native meadow or tule (= bulrush) hay can be produced on flood meadows serving as prime waterfowl habitat.
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