Fescue Rescue

Conversions to Nontoxic Fescue on the Rise

Jim Patrico
By  Jim Patrico , Progressive Farmer Senior Editor
The Alliance for Grassland Renewal helps beef producers convert pastures to nontoxic grasses. (DTN/Progressive Farmer photo by Jim Patrico)

Tall fescue infected with the high levels of an endophyte fungus can be devilish. The toxins it produces can wreck cows and stockers by slowing gain, reducing pregnancies and even causing hoof loss. In Missouri alone, estimates of the cost of fescue toxicosis top $240 million per year, said Craig Roberts, University of Missouri Extension state forage specialist.

Pasture conversion to a nontoxic tall fescue can help, especially now that nontoxic endophyte tall fescues are available. Cost is high -- $175 to $240 per acre for the fescues -- but payback in today's cattle markets could be as short as two years. Problem is, beef producers have heard this before and might be reluctant to tear up one kind of tall fescue to plant another type.

That's why the Alliance for Grassland Renewal is working hard to get the word out to "spray, smother, spray" toxic fescue fields and plant anew with novel endophyte tall fescue (NETF) varieties, which don't contain the fungus that causes toxicosis. "It will pay going forward," said Justin Sexten, University of Missouri animal nutritionist.

His comment is especially apt in a time of strong beef prices, which shorten the return on investment on pasture improvements.


Cattlemen have known about the dangers of toxicosis for generations and some producers got excited about 30 years ago when strains of endophyte-free tall fescue became widely available. Their excitement lasted only until the first drought, when those hard-earned tall fescue pastures died and did not come back to life. Turns out, endophyte-free tall fescue is "a very wimpy grass," Roberts said. Tall fescue needs some endophyte to strengthen it against stress. "When I have the endophyte, I am Superman," he said. "Without it, I am Clark Kent."

Luckily, New Zealand scientists have worked on the endophyte issue for a long time. In 1997, they isolated a nontoxic, naturally occurring strain of endophyte that could keep both tall fescue and cattle strong. Plant breeders at the University of Georgia were able to incorporate it into a NETF variety. Jesup MaxQ, which is adaptable to most areas in the U.S. where tall fescue flourishes, was born. Other varieties have followed.


The Alliance, which was formed in 2012, consists of partners from the University of Missouri, Natural Resources Conservation Service, not-for-profit groups, farmers, seed companies and testing labs. Its board of directors includes members from Georgia, Missouri, North Carolina and Oregon. The Alliance's goal is to educate producers about the costs and benefits of NETF varieties. To that end, University of Missouri Extension held a series of workshops this spring on the costs and benefits of renovating tall fescue pastures.

"This makes economic sense," Sexten said of converting toxic tall fescue fields to NETF.

Conversion, he said, can cost between $175 and $240 per acre, which is a wide range but reflects key differences in situations. The lower figure, for instance, would include minimal labor costs in the equation. The higher cost is based on university experience, which is heavy on labor costs. Seed costs, chemical costs and expenses related to smother crops vary less.

Benefits are based on Sexten's estimates of return on investment (ROI). With today's beef prices, ROI is much quicker than in the recent past.

Recent studies indicate fescue toxicosis can lower gains by around 140 pounds per acre over a 200-day grazing season for typical stocking rates. At $1 to $1.24 cwt, that amounts to a loss of $140 to $175 per acre per year. Convert to NETF, and those losses become gains for the life of the tall fescue stand, which can be more than years.

Cow/calf producers enjoy similar benefits. Increased birthing rates after conversion from toxic tall fescue are valuable, as is improved milk production. Sexten also pointed out that calves and replacement heifers are essentially stockers for part of their lives and, therefore, receive similar average daily gain benefits from conversion.


"Spray, smother, spray" refers to the pasture-conversion process. Spray with a herbicide to kill the tall fescue. Smother with a variety of cover crops. Spray again to kill the cover. Seed with NETF varieties.

Smother crops could lower the conversion cost if they have value as forage species, such as pearl millet or sudangrass. Producers should avoid species that might compete with tall fescue. Other smother-crop options include soybeans, which also can pay dividends at harvest. If there is no hurry to make a conversion, a two-year corn and soybean rotation also has merit.

The first year after an NETF is seeded, production will be light, and so should grazing.

When seeding, consider no-till. It is much less expensive than the alternatives.


Mt. Vernon, Mo., cow/calf producer Darrel Franson has a horror story he shared with one of the spring tall fescue workshops. As he was in the process of converting toxic pastures to NETF, he ran out of forage and moved some of his cows onto some rented ground. The animals had gotten used to nontoxic food, and when he moved them to toxic pasture, "I ran myself into a wreck," Franson said.

A few days later, he noticed his cattle were suffering, "limping all over the place," and he even had to put some cows down.

His lesson from the experience: "Don't let them become naive to the toxin. Move them back and forth [between toxic and nontoxic fields if you don't have enough NETF acres to feed them]."

Despite that experience, Franson said, NETF is the "best thing that has come along for Missouri pasture agriculture since intensive grazing."

He began converting from toxic tall fescue to NETF in 2001 and noticed an immediate improvement in herd health, calving rates and profits. "I have the records to prove it," he said.

It cost him about $200 per acre to convert his tall fescue acres. With a stocking rate of 1.63 cows per acre, he figures a $326 pasture-conversion-rate cost per cow. Improved performance in gain and calving gave him an extra $220 per cow. By his numbers, payback on his investment was less than two years.

"It's not magic; it's science. When we take the poison out of the feed, they do better," Franson said.

Several seed companies sell NETF, including Pennington, Barenbrug, DLF International and Mountain View. Producers should be sure to buy a novel endophyte, not an endophyte-free tall fescue. They should also look at the seed tag for the Alliance logo, Roberts said.


Jim Patrico