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Range, Pasture, and Forage Resources of the Southern Plains Sand Sagebrush - Mixed Prairie William A. Berg Definition, composition, and structure. Sand sagebrush (Artemisia filifolia) , growing to a height of one m, is the visual dominant in this cover type where it may attain 7 to 50% canopy cover. Perennial grasses (short, mid, and tall) are the major complement to the sagebrush. Blue grama (Bouteloua gracilis) and sand dropseed (Sporobolus cryptandrus) often provide much of the basal cover and forage production. Sand bluestem (Andropogon gerardii var. paucipilus), little bluestem (Schizachyrium scoparium), and switchgrass (Panicum virgatum) can be important forage producers and provide a tall-grass aspect if grazing by domestic livestock has not been excessive. Prairie sandreed (Calamovilfa longifolia) is a major warm-season grass in the northern part of this cover type, and the cool-season grasses, western wheatgrass (Agropyron smithii) and needleandthread (Stipa comata), are important. Sand paspalum (Paspalum stramineum), fall witchgrass (Leptoloma cognatum), and sand lovegrass (Eragrostis trichodes) are important warm-season grasses in the southern part of this cover type, and Texas bluegrass (Poa arachnifera) is the only important cool-season perennial. Seasonally abundant annuals may include hairy indianwheat (Plantago purshii), sixweeks fescue (Vulpia octoflora), annual bromes (Bromus japonicus, B. tectorum), lambsquarter (Chenopodium spp.), buckwheat (Eriogonum spp.), mint (Monarda spp.), and sunflower (Helianthus petiolaris). Perennial forbs, usually not abundant, may include western ragweed (Ambrosia psilostachya), stickleaf (Mentzelia spp.), hairy goldenaster (Chrysopsis villosa), spiderwort (Tradescantia occidentalis), and scurfpea (Psoralea lanceolata). Geographic distribution. - This type covers approximately 5 million ha in the Central and Southern Great Plains from southwest Nebraska, through eastern Colorado, southwest Kansas, and northwest Oklahoma. Much of this cover type is in bands of sandy mantle 5 to 20 km wide parallel to major drainages (South Platte, Arkansas, and North Canadian Rivers) and in narrower bands parallel to smaller drainages.Ecological Relationships. - Deep sandy soils (loamy sands and sands) on hilly landscapes without well-defined surface drainageways are the substrates for this cover type. Faster infiltration and less water loss to evaporation make sandy soils more efficient than finer textured soils in supplying water to perennial plants in this region where much of the precipitation (ave. annual pptn. 300 to 600 mm) falls during the growing season, high winds are common, and summers are hot. The more favorable soil water relationship allows this cover type to extend westward as stringers into the short grass prairie. The major range management practices in this cover type are: controlling stocking rate and season of use, use of complementary farmed forages, and controlling sand sagebrush with herbicides. Sand sagebrush is believed to increase in density as grazing pressure increases, however, canopy cover by sand sagebrush showed no major trend over 40 years under moderate grazing or in exclosures. The wind erosion potential is high on drastically disturbed areas and on limited areas farmed within this cover type. Most of the farming is with sprinkler irrigation: areas that were dryland farmed have largely been reseeded to native grass, or on the southern edge of the type, to weeping lovegrass (Eragrostis curvula). Prepared by W. A. Berg USDA, ARS Woodward, OK 73801
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