As Corn Belt states seek ways to curb nitrogen flow from farms into the Gulf of Mexico, new research suggests winter cover crops can help.
Research from the University of Illinois finds widespread planting of cereal rye in Illinois could reduce nitrate in the state’s tile drainage water by 30 percent. The team simulated both cover crop planting and fertilizer timing under real climatic conditions in Illinois between 2001 and 2020. They used a crop simulation model known as Decision Support System for Agrotechnology Transfer, which allows multi-year growth projections for more than 42 crops.
Two management implications were revealed in the study. One is that farmers should apply a winter cover crop, such as cereal rye, to reduce tile water flow and nitrate loss by 25 and 30 percent, respectively. The data also reinforced that farmers should switch to spring fertilization, if possible.
Cover crop adoption remains low in Illinois and the Midwest despite the availability of cost-sharing programs and growing evidence touting benefits.