Tall fescue is a hardy, popular, cool season perennial grass that can grow on a variety of soils in a variety of climates. It is grown on an estimated 35 million US acres. Changing to endophyte-free fescue may not be the best idea because the endophyte increases the forage's hardiness and promotes growth on marginal soils. Another option is to diversify a pasture with other forages. This helps reduce fescue toxicity by diluting the concentration of infected fescue.
Nitrogen fertilization appears to increase ergovaline levels in endophyte-infected fescue.
Ergovaline levels also increase as plant matures and seed heads form. Keeping livestock off fescue pastures after seed heads appear is advisable, but not always practical. If you cut tall fescue for hay, do it prior to seed head formation, otherwise the hay and remaining stover will be high in ergovaline. There are three main methods of eliminating endophyte infected fescue. They all involve eliminating the existing fescue, and replanting with endophyte-free fescue seeds .