When and how to terminate a cover crop in spring varies by farmer, but the practice usually has at least one common denominator – glyphosate – and it’s in short supply across much of the country.
Ohio farmer T. J. Rose says while he has enough glyphosate stored from last fall to terminate most of his cover crops this spring, he would need to buy more to handle any post-emergence weeds that might show up in his corn and soybeans.
“I usually don’t buy 100% of my chemicals in December, because I’m not 100% sure of exactly what I’m going to plant come spring,” says Rose, who farms and owns a cover crop seed business, Ohio Cover Crops, LLC, northwest of Columbus, near Bellefontaine. Continuing Coverage: Crop Protection and Ag Products In Short Supply
Because glyphosate is at a lower cost point relative to other chemistries, it’s most often the product of choice to terminate cover crops, says Ken Ferrie, Farm Journal Field Agronomist.
“But because it’s fairly cheap, a lot of guys don’t buy it until they need it,” he says.
This season, glyphosate cost is a factor to consider. Sam Taylor, vice president at Rabobank, tells Farm Journal that glyphosate prices are up 50%.
“It’s a big increase in a very short period of time,” he says. “But I think that one of the things that we can hope for is that if you look at the relative cost – and your cost of production with agrichemicals versus seed versus macronutrients – it is a smaller piece of the direct-cost pie.”
With concerns about glyphosate availability, Rose says he is directing his customers to their local retailers to get advice on what to do to terminate cover crops, because there is no one-size-fits-all solution.
“It’s a loaded question, because it depends on the crop, the timing, the weather and what stage of growth you’re in,” he says.
Contingency plans. Iowa State University field agronomist Meaghan Anderson says she has not heard any farmers in central Iowa say they can’t get glyphosate, though she has heard it’s in tight supply.
She recommends that farmers evaluate their weather conditions to determine whether they can reduce their glyphosate rate and stretch the product, as opposed to trying to pivot to a completely different product or practice.
“On a per-pound acid equivalency, farmers might be able to use three-quarters of a pound acid equivalent and still get an effective kill,” she says.
“Plan B, C or D would often be dramatically less effective than glyphosate. The consistency often isn’t there with glufosinate or paraquat to get the job done,” she adds.
Tillage could an alternative option to glyphosate, but it has to be fairly aggressive and, possibly, done more than once to be effective.
“Then there’s the concern that farmers planted a cover crop to meet certain goals, and tillage could eliminate some of the benefit they are getting from that cover crop,” Anderson says.
For farmers in dry areas, she advises using moisture availability as a guide for termination timing.
“This may not be the year in those dry areas to let rye get 5’ tall and headed out before you terminate it, if you’re going to soybeans,” she says. “Starting this Sunday, we have a fantastic forecast for central Iowa, so assuming the winds are low we might have a great opportunity to terminate cover crops.”
Anderson adds that before farmers terminate cover crops, they might want to check crop insurance guidelines and see how they compare to what university Extension specifies.
Continuing Coverage: Crop Protection and Ag Products In Short Supply
Win the Furrow: Cover Crops Require Different Management
Glyphosate, Some Other Crop Protection Products In Tight Supply
Glyphosate, Glufosinate Prices Up 50% in Some Cases Due to Industry-Wide Shortages
