Tall fescue is a high yielding and persistent cool-season grass. Compared to other grasses, fescue grows especially well in the fall, and it often is used for winter grazing.
Old fescue varieties often have an internal fungus, or endophyte, that produces chemicals that help the plant resist insects and diseases, which is good. But some of the chemicals also affect body temperature regulation, blood flow, and feed intake in livestock.
Horses can be very sensitive. Mares can abort or have stillborn foals, or they may fail to produce milk. In cattle we often see rough hair coats and more time spent standing in water or shade during summer. Cows produce less milk and often have difficulty conceiving. In winter, a condition called “fescue foot” can cause animals to loose hooves, ears, or tail switches during cold weather.
Many new fescue varieties, though, have been developed to be “endophyte free”, or they contain a novel endophyte. These fescues are very safe to graze, says University of Nebraska Extension forage specialist Bruce Anderson.
Research in Nebraska under both dryland and irrigated conditions has shown that many of these varieties are highly productive and have good survival. Many producers are beginning to use them very successfully in their grazing programs, he reports and says, “I think they are especially well suited for cow-calf operations.”
He concludes, “Tall fescue used to be a grass we avoided, but since new varieties do not have the toxins of old fescues, consider using it for your new plantings.”