Growth Responses of Perennial Cool-Season Grasses Grazed Intermittently

Abstract

Eight introduced and two native perennial cool-season grass varieties were grown for comparison in the highly variable climate of western Kansas. Grasses were seeded in a randomized complete block design with four replications on two different range sites. Grasses were grazed in 2000-2002 when vegetation height reached approximately 12 inches. All but one of the varieties produced greater dry matter yield than the native western wheatgrasses during the first year. However, tall wheatgrass and the native western wheatgrass varieties were among the highest yielding and had the greatest tiller numbers during 2002, a drought year. Most varieties produced 1.5 to 4.0 times more forage in 2001, a wet year, than in 2000 or 2002. With stress from grazing and lack of precipitation, cool-season grasses had greater yield response if greater numbers of tillers were present. Establishing and maintaining high tiller densities in stressful environments is a key contributor to productive grazed perennial cool-season grass stands in the western Great Plains.