cover crop

Managing and killing a cover crop in the spring is always a concern. For some farmers in Southern states that is especially difficult, as annual ryegrass has developed resistance to some herbicides.

Like any crops, covers come with challenges. One that may be facing farmers in the short run is seed delivery

Adam Dahmer of Advanced Cover Crops in Marion, Ill., is concerned about getting seed to fields in Illinois and other Midwestern states.

“The biggest challenge we’re going to see with cover crops this year is getting it here,” he said. “It’s trucking logistics. ... Farmers need to make sure the seed is sitting in their shed the day they need it.”

The quantity and quality of that seed is equally important, Dahmer said. He urges growers to think twice before cutting corners.

“You get what you pay for. By that, I mean if you’re looking at using cover crops for weed suppression, you’ve got to make sure you put enough cereal rye out there to take care of it,” he said. “You’ve got to have the right seeding rates for the right application. To overcome that obstacle, connect with someone in the seed industry who is out for the benefit of your farm and not just for the benefit of your checkbook.

“You need to have a dollar amount in mind that you don’t want to surpass, but you also want to have the right tools to do the job. You don’t want to show up to do a big job with a little tractor.”

Killing a cover crop in the spring is always a concern. Some farmers in Southern states are having an especially difficult time, as annual ryegrass resistant to some herbicides have sprung up.

“In Tennessee and other Southern states, they’re having a hard time controlling resistant annual ryegrass,” said Ron Krausz, superintendent of Southern Illinois University’s Belleville Research Center.

Resistance or not, killing covers can be problematic.

“Especially with annual ryegrass, you may have only three or four days in March that you can actually spray it to kill it,” Krausz said. “Those are a few of the downfalls of cover crops. But it’s nothing that can’t be overcome.”

Dahmer said it is vital that farmers considering a cover crop program do some long-term planning. For one thing, he said, farmers should be thinking 18 months ahead about basics such as what their goals are and what covers they are going to plant.

“Also, what is our equipment setup? For example, if you want to plant your corn into hairy vetch, how are you going to apply your nitrogen?” he said. “That’s something a lot of guys don’t think about when it comes time to sidedress their nitrogen. You can’t just run out there with a normal applicator and not drag the field up in a ball.”

Dean Oswald agrees that choosing the right varieties is key. Blends can pose problems when it comes time to burn down the crop in the spring.

“It can be a problem with annual ryegrass when you have a blend of more than one variety,” said Oswald, a cover crop specialist with the Illinois Council on Best Management Practices. “It might kill one variety and not another because it’s later maturing; the chemical action isn’t the same. If you purchase something that is winter hardy and is all the same variety, chances are you’re going to be able to get a good kill of it.”

Farmers shouldn’t encounter problems with killing covers if they pay attention to the basics, including using the right equipment the right way.

“Sometimes guys don’t have their sprayers set up right,” Dahmer said. “There are instances where guys haven’t had their tanks agitated. If you’re going to spray ryegrass, make sure your pH is the right spot, and the chemical is mixed well with the water. That’s not just cover crops; it’s agronomics.”

One possible problem with a cover crop system is pest control.

“With any cover crop, you always have insects coming in the spring and laying eggs,” Krausz said. “You go back to the early preplant days, and one advantage was we could kill the weeds off so there are fewer moths laying eggs.”

Cost is also a factor. Krausz pointed out that farmers must be prepared to pay money up front for benefits that don’t come immediately.

“It does cost more money, and it doesn’t add anything in the short term,” he said. “But over the long term, it does have a lot of positives for soil health. They may not see returns in the first three years, but down the road they may see big benefits.”

Sign up for our weekly CropWatch newsletter

* I understand and agree that registration on or use of this site constitutes agreement to its user agreement and privacy policy.

Nat Williams is Southern Illinois field editor, writing for Illinois Farmer Today, Iowa Farmer Today and Missouri Farmer Today.