Enhancing Corn Yield in a Winter Cereal Rye
Cover Crop System in Northeast Iowa
Water quality impairment related to nitrogen (N) is a concern in Iowa, including meeting nitrate (NO3) drinking water standards and reducing the amount of N lost to the Gulf of Mexico. The Iowa Nutrient Reduction Strategy science assessment identified a rye cover crop as an important in-field management practice for reducing N and phosphorus (P) loss from fields (31% NO3-N and 29% P), and for reducing soil erosion. However, the science assessment identified a corn yield reduction of 6 percent when grown following a rye cover crop. Lower corn yield with use of a cover crop is unacceptable to farmers, so it is important to identify practices that minimize impact on corn establishment, early-season growth, and yield. The objective of this project was to study production practices that might enhance corn yield when grown in a winter cereal rye cover cropping system.