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Ridding Farm of Toxic Fescue Begins on Infected Hay Fields

COLUMBIA – Renovate hay fields first when replacing toxic fescue with new novel endophyte varieties.
“Toxin-free hay makes establishing toxin-free pastures easier,” says Justin Sexten, University of Missouri Extension beef nutritionist. “Seed from infected hay reinfects new pastures.
“You must start somewhere, as you can’t replace all old pastures at once,” Sexten says. “Start with an area with a big impact on the grazing operation.”
A hayfield can produce much more per acre with a new novel endophyte variety. That allows taking other pastures out of production and maintaining the cow herd at the same time.
Infected Kentucky-31 fescue cannot be fertilized to boost yield, as nitrogen increases toxin output. With a novel endophyte variety, adding fertilizer increases hay with no bad side effects.
Kentucky-31 fescue, the dominant grass in Missouri pastures, has a fungus living between cell walls of the plant. Toxin from the fungus protects the plant but harms grazing animals. New novel endophytes protect the grass without harming livestock.
“In feedback I get, producers see the benefit of toxin-free pastures,” Sexten says. “But they often ask how to fit novel endophyte into their system.”
Other starting points are pastures used for reproduction or gains in the beef herd. That can be breeding pastures or those for growing replacement heifers. Weaned calves gain more weight on renovated fields.
“The first acre will be the toughest to convert,” Sexten says. “You just have to go at it like planting a crop. This isn’t easy as broadcast frost-seeding legumes into grass pastures. But it’s not hard to do.”
Fescue schools emphasize proper settings of planting drills. Planting depth of a quarter inch is critical to success in planting. Adjusting the drill takes time, Sexten says.
“With the price of seed corn, no one goes out, fills the planter boxes and starts planting without adjusting the planter,” Sexten says. “The cost is too high not to do it right.
“Once you begin renovation, additional acres are easier. It just rolls along.”
Sexten knows the first step is a big one. “It takes figuring out where renovation works best, first.”
The Alliance for Grassland Renewal will hold four novel endophyte fescue schools across the state. Starting March 30, schools will be held at Mount Vernon, Cook Station, Columbia and Linneus.
Each will be held at a University of Missouri research farm that has plots of all available novel endophytes. The varieties can be seen in side-by-side grazing plots.
The Alliance, a first in the nation, brings together seed companies, government agencies, testing lab and farmers working with MU Extension.
The payoff for conversion is better gains, better reproduction and many more benefits, Sexten says. “Too many farmers do not realize the losses from grazing infected fescue.”
Advance registration is required, as space is limited in the fescue schools. Details are at
Pasture conversions will be most rewarding when beef prices are high, organizers say. In times of low prices, extra gains will make profits possible.