Comparison of seeded and native pastures grazed from mid-May through September.

Abstract

Cool-season introduced grass species are not recommended for season-long grazing in the northern Great Plains. They mature earlier than native species, which leads to an earlier loss in forage quality and palatability. A study conducted at Mandan, N.D., compared liveweight gains of yearling steers grazing crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schult.], smooth bromegrass (Bromus inermis Leyss.), and western wheatgrass [(Pascopyrum smithii (Rydb.) Love] and level native prairie (Class II and III land) and hilly native prairie pastures (Class IV and VI land), season-long. A set stocking rate of 1.5 AUM ha-1 was used from mid-May through late September in 1988, 1989, and 1990. Caged standing crop was higher from the seeded pastures than from the native pastures but liveweight steer gain was highest from the level native. Three-year average gains were 124, 114, 108, 106, and 105 kg per steer for level native, smooth bromegrass, western wheatgrass, hilly native, and crested wheatgrass pastures, respectively. The seeded cool-season grass pastures, grazed season-long at a rate 25% higher than that recommended by the SCS for native range, produced acceptable liveweight steer gains without additional inputs. Season-long grazing may provide an alternative use for marginal cropland and other highly erodible land that has been reseeded to cool-season species.