Online tool offers cover crop possibilities for Iowa growers

Thursday, January 17, 2013

AMES, Iowa – Iowa farmers are encouraged to check out a new online tool that will help them select the right cover crop for their operations.

The Cover Crop Decision Tool was developed by the Midwest Cover Crops Council to help farmers select cover crop species based on their main crops, available planting windows and what they needed from the cover crop such as stopping erosion, livestock forage or to control weeds. Last year, for example, farmers throughout the Midwest were urged to plant fall cover crops as a way to keep nitrogen in the soil that was not used by crops during the drought-stressed growing season.

New data updates the Cover Crop Decision Tool so that it can be used for Iowa crops and conditions.

“This tool should be a big help for farmers planning, considering or just thinking about how and where they might use cover crops,” said Tom Kaspar, USDA plant physiologist involved with the Iowa Cover Crops Working Group that helped develop the tool. “The planting window for each species is adjusted for each county in all participating states, a unique aspect of this resource.”

Mark Peterson, who farms about 300 acres of row crops in southwest Iowa near Stanton, said he would welcome the free, online tool. After several years of consideration, he planted about 80 acres of cover crops for the first time last fall. He used a couple methods, including aerial seeding of winter rye by helicopter before soybean harvest.

“I wanted to make sure that something worked,” he said. “I’m also comfortable that the winter rye by itself will save enough soil that even though it might not show up in the bottom line on a year-to-year basis, it will be worth it in the long term by keeping the soil where it needs to be.”

Peterson is a farmer-cooperator in the Iowa Cover Crops Working Group that has representatives from Iowa Learning Farms, Practical Farmers of Iowa, Iowa State University Agronomy Department, USDA-ARS National Laboratory for Agriculture and the Environment in Ames, and the Leopold Center for Sustainable Agriculture. All organizations have contributed to demonstrations and research related to cover crops.

Kaspar said the tool is specific to region, soil drainage class and includes information about a variety of cover crop species: non-legumes such as oats, buckwheat, barley, triticale and winter wheat; brassicas such as radish, oilseed and turnip; legumes including alfalfa, red clover and cowpeas; and five mixes. The tool suggests cover crop species and potential planting date windows that usually provide good establishment and growth, based on 30-year average frost dates in the user’s county.

To find the Cover Crop Decision Tool, go to

The tool went online in 2011 with information suited for growing conditions in Indiana. It was expanded to Michigan, then Illinois, Minnesota, Ohio, Wisconsin and the Canadian province of Ontario. Iowa is the latest state to be added to the tool. In addition to main crops of corn, soybean, wheat and dried beans, the tool also offers cover crop choices for producers growing warm- and cool-season vegetables.


Tom Kaspar, USDA-ARS National Laboratory for Agriculture and the Environment, (515) 294-8873,

Sarah Carlson, Practical Farmers of Iowa, (515) 232-5661,

Jeri Neal, Leopold Center, (515) 294-5610,