Submitted to: Popular Publication
Publication Type: Popular Publication
Publication Acceptance Date: July 20, 2003
Publication Date: June 20, 2004
Citation: Skinner, R.H., Gustine, D.L., Sanderson, M.A. 2004. Growth of pasture mixtures under moisture stress. Pennsylvania Forage and Grassland News. 14(3)p. 3. Technical Abstract: A primary goal of grazing land managers in the northeastern USA is to improve forage production during summer months when heat and moisture stress limit growth of cool-season forages. Pastures in the northeastern USA typically are dominated by Kentucky bluegrass and white clover, both of which are sensitive to water deficits and elevated temperatures, providing only limited forage during summer months. Evidence suggests that pasture productivity under harsh environments can be increased by increasing species diversity. Our objective was to compare forage production of the white clover-Kentucky bluegrass mixture that typically dominates northeastern USA pastures with more drought tolerant species mixtures. A five-species mixture containing chicory, orchardgrass, Kentucky bluegrass, perennial ryegrass and white clover had the greatest dry matter production at all moisture levels. Yield in that mixture increased by 89% in the dry, 61% in the normal and 43% in the wet treatments compared to the white clover-Kentucky bluegrass mixture. Increased yield was primarily due to the robust growth of chicory which dominated the mixture. In addition, white clover growing in the mixture with chicory experienced less drought stress and had greater relative growth rates than white clover growing with Kentucky bluegrass. Inclusion of the deep-rooted species, chicory, appeared to be more important than increasing the number of species in improving productivity under stressful environments.