Diversifying tall fescue pastures with native warm-season grasses and white clover improves beef cattle performance

Abstract

Tall fescue (Schedonorus arundinaceus (Schreb.) Dumort., nom. cons.) is a productive and stress-tolerant cool-season grass, but endophyte toxicity can reduce beef cattle performance. Creating biodiverse pastures with perennial native warm-season grasses (NWSGs) could alleviate fescue toxicity by providing alternative sources of forage. Legumes added to NWSG mixtures could also provide floral resources for insect pollinators, reseeding, and benefit cattle performance. A 3-year grazing study conducted in Virginia tested the feasibility of this biodiverse grazing system to improve animal performance and floral resources for pollinators. The experiment consisted of three treatments applied to 1-ha pastures: (1) biodiverse—70% planted to tall fescue with 30% planted to a NWSG and legume mixture, (2) shade—100% tall fescue pasture supplemented with artificial shade, and (3) control—100% tall fescue pasture with no shade. Pastures were continuously stocked with cattle each summer from 2021 to 2023. Average daily gain of cattle in the biodiverse treatment ranged from 31% to 85% greater than other treatments likely because animals had access to NWSG and white clover (Trifolium repens L.) forage. Midday body temperatures of cattle in the biodiverse treatment were also 0.3°C–0.5°C lower than those on the control treatment. Flower production was limited to white clover. Overall, findings from this study suggest that diversifying tall fescue pastures with NWSGs and white clover can lead to improvements of beef cattle performance and may reduce the level of heat stress.