University of Missouri plant science professor Craig Roberts says research done in Missouri shows that fescue toxins cost the state’s beef industry $240 million annually. He says producers do not always anticipate the damage it is causing to their herds.
“Fescue toxins are just slow-acting, and they rarely kill the animals, so people commonly have put up with these without fully appreciating the level of damage to their herd health, productivity and profitability,” Roberts says.
The toxins released from this tall fescue can cause a drop in gain, a drop in milk production of about 30 percent and reproductive problems.
Roberts says many in Missouri try to plant orchardgrass, bromegrass or ryegrass, but they do not persist. Fescue is persistent. Getting rid of the toxicosis in fescue is a better way to go. Replanting with a fescue that does not contain the toxin could be the way to get away from the toxicosis.
When replanting a fescue pasture, Roberts uses a recipe that involves spray, smother, spray. In May in Missouri, he recommends spraying the toxic fescue with a high rate of glyphosate. That will kill most of that fescue, except the fescue left under manure patties and seed in the soil.
Then comes the smother step.
“We plant a summer annual, and we’re talking a cereal plant like a pearl millet or sorghum-sudan, something with a wide row spacing. That’s a really good forage, so the cattle can graze it, and as the summer goes along, they’re using that forage in June, July and August,” Roberts says.
At the end of August, producers will see as they walk down the row of the summer crop that old fescue tillers are coming up and old seed is sprouting in the seedbank. That is when it is time to spray again.
Once the spray, smother, spray process is complete, then it is time to plant the fescue that does not include that toxic endophyte. For the last 10 years, Roberts has seen other tall fescues that have endophytes but do not contain the toxic endophyte. These so-called “novel endophyte” tall fescues are being planted more and more in the U.S.
These novel endophyte tall fescues are safe for dairy and beef cattle, as well as small ruminants.
When planting the novel endophyte fescue, he suggests planting in the fall. He does not encourage planting other grasses with it because he wants a strong stand of the new fescue.
“We just don’t like any crowding when we’re trying to plant that novel endophyte. There’s no reason to put the whole field at risk planting clovers or grass,” Roberts says. “If you plant a clover or alfalfa, you’ll have some competition and your grass may not be well-established.”
To avoid a monoculture, he suggests planting the novel endophyte fescue in the fall and then frost seeding in clovers or other legumes that are easy to frost seed in January. Producers can drive a buggy over the field to plant it. The seeds drop on the surface, but during the winter, the ground will freeze and thaw and suck the seed into the soil. When spring comes, it germinates.
“In general, come back in early September and plant into that soil that’s been double sprayed. You plant into that straight grass knowing that you’ll add the other forages later. That’s a very nice recipe,” he says.
Roberts adds that producers could manage Kentucky 31 tall fescue without replanting. However, doing so would include input costs every year and a lot more management.
He has confidence that these novel endophytes are here to stay, so replanting is a good option for producers.
“We’ve seen fad forages come and go. That’s not a fad. There are more and more plantings of this,” Roberts says. 
Wendy Sweeter is a freelance writer based in South Dakota.
PHOTO
The impact of fescue doesn’t always equate to fatal toxicity, but often in reduced reproduction or milk output. Photo by Lynn Jaynes.
