By Jake Christie
Cover cropping has existed for a few hundred years. Farmers plant winter-hardy plants to protect the soil and plow them under to nourish it for cash crops like corn or wheat.
Now, instead of plowing the cover plants, researchers want farmers to harvest them, said Erin Meier, director of Green Lands Blue Waters a Minnesota group that advocates increasing soil health by ensuring there is something living on farmland year round.
But farmers need to terminate cover crops to qualify for subsidies, according to the United States Department of Agriculture.
Cover crops solve the problem of erosion and fertilizer runoff that barren farmland creates, Meier said.
Jessica Gutknecht, associate professor in the department of Soil, Water and Climate at the University of Minnesota.
They can also lead to better yields for cash crops, said Todd Hogrefe, director of the National Fish and Wildlife Foundation’s central regional office.
Only about 6% of farms practice cover cropping, but that number is growing, said Russ Gesch, a plant physiology researcher with the United States Department of Agriculture.
However, cover crops need extra labor and fertilizer and these extra costs can be a barrier for farmers interested in cover cropping, said Gesch.
The cost for some cover crops can reach $40 per acre and when even a small farm can have hundreds of acres, the costs add up, Hogrefe said.
Federal and state subsidies for cover crops exist, but the demand exceeds supply, he added.
Potential cash cover crops are being developed by The United States Department of Agriculture and The Forever Green Initiative.
They could protect soil through winter, and then be harvested when there’s something else growing, giving farmers a concrete economic incentive to adopt the practice, Gesch said.
Oilseeds like pennycress and camelina show promise, Gesch said.
Pennycress is a winter annual oilseed that can be used for biodiesel, and since it would grow through the winter it wouldn’t take away land from food crops, Gesch said.
The byproduct of processing camelina can be used as a high nutrient feed for livestock, while the oil from the seed could be used for human consumption, according to Green Lands Blue Waters.
Cash cover crops could offer incentives for farmers wary of the upfront costs of regular cover crops. But they don’t qualify for government subsidies, Gesch said.
Green Lands Blue Waters also advocates for using agroforestry and perennials to grow plants year round.
Having land covered also creates an entire ecosystem for microbes which eventually leads to the build up of organic matter as microbes move through their lifecycle, Gutknecht said.
The lifecycle of microbes and plants creates a system that can filter and hold more water and nutrients, which provides a buffer against drought and unpredictable rain, Gutknecht said.
The vegetation could also create a habitat for some animals that would otherwise be barren farmland, Hogrefe said.