A pair of new research projects will examine whether cover crops can reduce nitrogen fertilizer runoff from farm fields in Minnesota. Too much nitrogen in rivers, streams and lakes can lead to excessive plant growth that degrades the water and robs it of oxygen.
One project will interseed cover crops late in the growing season while corn and soybeans are still in the ground, and measure how much nitrogen is taken up by the crops instead of leaving the fields through tile drainage. It will be led by Jeff Vetsch, soil science research manager at the University of Minnesota Southern Research and Outreach Center in Waseca. Vetsch will apply three different rates of nitrogen to the fields, and plant several different types of cover crops to compare how they perform. Cover crops typically grown in Minnesota include oats, annual rye, forage turnips and radishes.
A second experiment will plant cover crop mixes from Grand Rapids to Lamberton and Waseca to study how well cover crops grow in dryer regions of southern Minnesota compared to cooler northern areas. University of Minnesota assistant professor and cropping specialist Axel Garcia y Garcia hopes to help farmers better understand what types of cover crops might work best on their farms. He will also measure nitrogen runoff from the fields, monitor plant diseases and weed populations, and study how different cover crop mixes can enhance diversity in the surrounding ecosystem.
Both projects are funded by the Minnesota Corn Growers Association, which spends about $4 million annually on research efforts through its research and promotions council. Nearly two dozen projects are currently funded, and the money comes from Minnesota’s corn check-off, which collects one cent for every bushel of corn sold to market.