By Julie Whitson
Even with excellent nutrient management, nitrate losses from corn and soybean fields can occur because these cash crops only grow and take up nitrate and water for five months of the year. Cover crops like winter rye can be an effective strategy for reducing nitrate losses to groundwater or tile drainage, because they can take up water and nitrate during the period between harvest and planting of the next year’s crop.
Tom Kaspar will discuss lessons learned from using cover crops to reduce losses of nitrate during the Iowa Learning Farms webinar on Wednesday, Dec. 13 at noon. Kaspar is a plant physiologist at the USDA-ARS National Laboratory for Agriculture and the Environment. Kaspar also is one of the leading voices on cover crops across the Midwest and one of the founding members of the Midwest Cover Crops Council. Kaspar’s research has focused on using cover crops and no-till to improve water quality and soil health in corn and soybean production systems.
“Over 15 years, tile drain monitoring on research plots in Iowa has shown that a winter rye cover crop reduced both nitrate loss and concentration in tile drainage by over 55 percent in a corn-soybean rotation,” Kaspar commented. “Farmers have shown that cover crops can be successfully grown in corn-soybean rotations in Iowa to protect and improve both soil and water.”