Downed corn

After storms rolled through the Midwest Aug. 10, many farmers faced damage, including corn knocked down in many fields. Producers have some options for downed corn in fields, although the best course of action can depend on a variety of factors, says Beth Doran, Iowa State University Extension beef specialist in Orange City.

“It depends on how down the stuff is, what the maturity is and whether they were experiencing drought,” she says.

As a first step, Doran says it is a good idea to check chemical labels that were used on the fields to make sure the corn can be fed to livestock. Producers should also check with crop insurance agents first to have an adjuster view the fields before pursuing feed options. After those basics comes an evaluation of how knocked down the corn is.

“How well is it standing?” Doran says. “Is it partially standing or is it down? Some of that corn is still plenty wet.”

Corn needs to be about 65% moisture to chop for silage and put in a bunker or pile. If it’s too wet it can have issues with spoilage. Doran says farmers can leave damaged corn as is to continue drying down if it is mostly standing.

“If they think they can let it stand and dry down until it’s ready, that would be ideal given the circumstances,” she says.

If the corn is too wet and is knocked down fully, producers can mow it off and then let it finish drying. Doran says rotary style heads work best for cutting corn. Farmers can windrow the corn or cut it into swaths. Windrows are slower to dry, which can risk more spoilage.

Mowing the corn into swaths allows for faster drying, but Doran says there is more potential for soil to spoil it. She says in general ag engineers recommend mowing into windrows, but it can depend on the situation. Producers can contact their equipment dealer for information on the best settings for mowing the corn.

“You want to cut against the downed corn,” Doran says. “Go against the direction that the crop’s going. And they’re probably going to have to go slower. It probably won’t be like a typical silage cutting.”

When the mowed corn dries, farmers can chop it for silage. She says producers should not expect to be able to get 100% of the corn picked up.

Gene Schmitz, a University of Missouri Extension livestock specialist, says it is important to get silage packed tightly.

“You just can’t overpack it,” he says. “If we don’t get the oxygen excluded we have a lot of spoilage.”

He says packing silage between hay bales or in a pile on the ground can be tough to get the edges packed tightly enough, but he says it is possible.

“We just lose an awful lot of feed value by not getting it packed well,” Schmitz says. “I’ve seen piles work as long as they’re packed well and packed out to the edge. Those edges are really critical.”

Doran says for drought stressed corn, it would be a good idea to test it for nitrates four to five weeks after chopping and packing it. The fermentation process will reduce nitrate levels, but if they are still too high producers can blend the silage with other feed and feed it to less-susceptible cattle, such as higher-weight calves and open cows. Cows that are pregnant could face more adverse effects from higher nitrate levels.

Doran says producers can also green-chop the corn and feed it, although nitrate levels won’t decrease that way.

“I would recommend they only chop what they can feed in one feeding,” she says, “and I would chop it in the morning.”

Farmers can reach out to Extension personnel if they have questions.

“There’s no standard answer,” Doran says. “I wish I could just give one answer. It’s just going to depend from farm to farm.”


Ben Herrold is Missouri field editor, writing for Missouri Farmer Today, Iowa Farmer Today and Illinois Farmer Today.