Potential for Use of a Perennial C3 Grass in a Warm-Temperate Region with Pastures Dominated by C4 Grasses

Tall fescue is a perennial cool-season forage grass utilized over an extensive area of the USA; however, adaptation is limited across the Coastal Plain region of the southeastern states including Louisiana. Stands of the original variety, Kentucky 31, from early plantings either failed to persist or were replaced as adverse effects on grazing livestock by an ergot alkaloid toxin from an association of tall fescue with an endophytic fungus were recognized. Management approaches can moderate the adverse effects allowing productive use of existing tall fescue pastures. Endophyte removal from tall fescue allowed development of useful cultivars for the primary tall fescue growing area, but these endophyte-free cultivars proved to be less persistent in marginal areas such as Louisiana. Recently available varieties with novel, nontoxin-producing endophytes have shown potential in northern Louisiana with stand persistence for 4 years on some sites. Cool-season perennial grass pastures can be realistic components of forage systems in areas such as northern Louisiana. Existing remnant stands can be beneficial with appropriate management, and, as indicated by ongoing research, new novel-endophyte varieties may prove useful on selected sites