by Ben Nuelle
Some farmers may be shy to try cover crops because they hear it robs them from good yields. A plant pathologist says a recent Iowa State study might help change their minds.
Iowa State University Plant Pathologist Alison Robertson says extension and outreach recently finished a study looking at the cover crop Rye and how it affects yields.
She says this is the number one concern with farmers when it comes to cover crops.
“One of the ideas behind that is maybe the cover crop is harboring pathogens that then infect the corn and population and the growth of the corn. We actually did a study where we terminated Rye at different times all the way from 21 days before planting to one day after planting.”
Robertson says timing is everything.
“If that termination interval between killing the cover crop and planting corn is very short, three to seven days, you increase your risk for seedling disease. An increased risk from seedling disease may mean you lose plants in the field which means reduced yield. Or you could get root rot and affect the vigor of the plant. Those plants are then held back because of the root rot. You get weedy plants that don’t yield anything so that might be where the yield penalty is coming from.”
She hopes more farmers will try cover crops after hearing about this study.