Cover crops usually are planted in the fall to protect soil over the winter and replaced with corn and soybeans in the spring. But an exceptionally cool and wet spring kept many farmers from planting, leaving their fields fallow.
Because many fields were left completely bare by prevented planting, Eileen Kladivko, Purdue Extension cover crop specialist, recommends planting a cover crop to avoid soil erosion and build soil quality.
Cover crops can increase a farm's long-term productivity by loosening soil structure, reducing nitrate leaching and adding organic matter, Kladivko said.
"There is no reason not to do something in the summer," she says. "Soil quality increases by growing things in it."
Jim Hoorman, Ohio State University cover crop specialist, says cover crop roots may create pore space, increasing the soil's water storage capacity.
"By decreasing compaction, surface runoff also decreases, so cover crops may potentially reduce flooding and future drought stress by increasing water infiltration and enhancing water storage in the soil profile," Hoorman says.
The Midwest Cover Crops Council has created an online tool to help farmers decide which cover crops to use on their farms. It is available at http://mccc.msu.edu.
To decide which cover crop to plant, growers should consider what they want to accomplish, whether they use a mix -- which can have multiple benefits -- and by which date they have to plant, Kladivko says.
"With prevented planting, growers have plenty of time to establish cover crops with good root growth before winter," she adds.
Within the cover crop selection tool, users can choose their states, counties, and what they want the crop to accomplish. The crops are grouped in sections by their characteristics.
Typically, grasses have the highest biomass and contribute the most organic material to the soil, Hoorman says. Legumes add nitrogen and can be a good choice if growers are planting corn next season.
Brassicas, such as turnips, radishes and canola, have large taproots that decrease compaction and make water channels.
The decision tool generates a chart of crops that meet users' needs, and recommended planting dates are shaded for each crop. These planting schedules match the times when the Natural Resources Conservation Service may help the grower through a cost-sharing program. The program offers funds to help growers pay for seed to plant cover crops on qualifying land.
It is important for farmers considering a cover crop to understand the insurance regulations. For example, while a producer taking a prevented-planting insurance payment for a certain field can grow a cover crop on it, the crop cannot be harvested as forage or for revenue.
Under the Risk Management Association guidelines for cover crops, growers must terminate the crop before May 15 in order to get crop insurance coverage on corn and soybeans planted in the same field. Because very few farmers were able to work in their fields before May 15 this year, Kladivko said RMA delayed that deadline for 2011 in Illinois, Indiana, Michigan and Ohio. By doing so, farmers could still qualify for prevented-planting coverage.
Producers still need to confirm their use of cover crops and submit written agreements through their insurance agents by July 15 this year, to keep them in compliance with all insurance requirements, Kladivko said.
Kladivko and Barry Fisher of Indiana NRCS authored a new publication, titled "Cover Crops for Prevented Planting Acres," which is available for free download at http://www.ag.purdue.edu/agry/extension/Documents/PreventedPlantingCovers.pdf.
More information also is available in a free NRCS guide sheet, "Cover Crops to Improve Soil in Prevented Planting Fields," at http://www.in.nrcs.usda.gov.