Productivity and Persistence of Summer-active and Summer-dormant Tall Fescue Cultivars in the Southern Great Plains

Abstract

Lack of persistence arising from high temperature and drought stresses during the summer limits lifetime productivity of tall fescue (TF) [Schedonorus arundinacea Schreb. (Dumort)] pastures in the southern Great Plains. A summer dormancy characteristic common in genotypes originating from the Mediterranean basin may provide a means of escaping heat and drought stresses encountered in the southern Great Plains. Two summer-active [Kentucky 31 (K31) and Jesup MaxQ (JES)] and two summer-dormant [Flecha MaxQ (FLE) and Prosper (PRO)] cultivars of tall fescue were planted at Booneville, AR, and Langston, OK, to test the effects of summer dormancy on persistence and herbage productivity. At Booneville no cultivar survived beyond two growing seasons. At Langston, summer-active cultivars were productive into Spring of a third growing season but did not survive the following summer. Summer-dormant cultivars at Langston partially regenerated in a fourth growing season but did not regrow after Spring harvest. At both sites annual and cumulative total yields over 2 or 3 years were significantly greater with summer-active than with summer-dormant types. Commercially available summer-dormant cultivars do not appear to offer survival benefits sufficient to offset low productivity in the southern Great Plains, where intermittent summer rain may prevent full expression of summer dormancy characteristics.