Use spray-wait-spray to renovate drought-stricken pastures

COLUMBIA, Mo. — Forage producers can convert tall fescue pastures to nontoxic novel-endophyte fescue without incurring the main expense usually associated with pasture renovation through mid-July.

Typically, the main cost to consider in the conversion process is having land out of production, says University of Missouri Extension state forage specialist Craig Roberts. Producers can make the best of a bad situation on drought-stricken pastures that show limited or no growth now, he says.

New fescue varieties produce no symptoms of fescue toxicosis, which costs the beef industry millions annually. Replacing toxic tall fescue with nontoxic novel-endophyte varieties offers animal health benefits, including improved weight gain, reproductive performance and milk production.

In a press release, Roberts said “The payback is enormous. And it’s a perennial payback. You keep getting your money back year after year.”

Roberts usually advocates the spray-smother-spray method of renovation, in which existing fescue pasture is sprayed with a systemic, non-selective herbicide such as glyphosate. The first spray kills most of the tall fescue plants. Then, the field is no-till drilled with an annual smother crop for cut hay or grazing. The field is sprayed again just before planting the new nontoxic variety.

But Roberts says this is a year when spray-smother-spray won’t work well. Smother crop seeds will probably not germinate due to lack of rainfall. Also, seeds that might germinate would further deplete the moisture stored in the soil profile.

Instead, Roberts recommends the spray-wait-spray method. This method requires having clipped in the spring to prevent seed heads from forming, and then spraying with glyphosate in the early summer. Six weeks later, the field is sprayed a second time. Soon after the second spray, the new variety can be no-till drilled into the killed stubble at recommended seeding rates.

Roberts and other forage experts in the seven-state Alliance for Grassland Renewal have found this method to be effective in 10 years of research in the southern U.S. It has also been tested successfully in mid-Missouri.

Roberts says that spray-wait-spray only works on pastures that have had seed heads removed before they are ripe. If seed heads are not removed, seeds fall to the ground and contaminate the pasture with toxic growth.

Renovation is costly, so Roberts recommends converting only part of a farm’s pastures each year. He suggests converting to novel endophytes initially on 10%-20% of their pastureland each year.

“Start small,” Roberts says. Novel-endophyte pastures also require a different style of management than tall fescue. Producers can learn more from their local MU Extension specialist or by attending forage schools offered by the Alliance for Grassland Renewal.

Researchers introduced endophyte-free fescue in the 1980s to prevent fescue toxicosis in livestock, but they found that it lacked the persistence of K-31 and other varieties. New novel-endophyte varieties released in 2002 have proved to be a breakthrough in modern-day agriculture, says Roberts. They show persistence, are resistant to drought, insects and disease and do well throughout the Fescue Belt.

For more information, visit www.grasslandrenewal.org.

This is part of an MU Extension series to help row crop and livestock producers manage drought. For more articles, go to https://mizzou.us/DroughtResources.