Cover crop management in corn and soybean cropping systems
In recent years, interest in adding cover crops to corn and soybean cropping systems has increased as their potential benefits have become more widely recognized. According to Andy Heggenstaller, DuPont Pioneer agronomy research manager, cover crops offer opportunities for improving soil quality and crop production efficiency, but they can also add new management challenges and risks.
Cover crops are best viewed as a long-term investment in soil productivity. The specific benefits of a cover crop depend on the species and growing environment. Selecting the right cover crop for your farming operation begins by identifying the specific functions you want the cover crop to provide. The primary benefits of cover crops in corn and soybean cropping systems include reduced soil compaction, soil nutrient retention and prevention of soil erosion. The most commonly used cover crops fall into one of three broad groups, including grasses, legumes and brassica. These groups are based on species, potential benefits and management considerations.
Research studies on cover crop effects on grain crop yields have reported a range of responses, depending on environment, cover crop species and management. Yield effects can also differ between corn and soybeans. Generally, legume cover crops and grass-legume mixtures are more likely to have a positive effect on corn yield than grasses alone. While this difference is not universal, it is likely to hold true across a range of locations and management scenarios. Additionally, regional differences in corn yield response to cover crops highlight the importance of soil and climatic factors. Cover crops are more likely to have a positive effect on corn yield in southern and eastern locations than in northern locations.
Getting the greatest benefit out of cover crops requires management intensity similar to corn and soybeans. Selecting the right cover crop for your farming operation begins by identifying a management goal, such as increasing soil organic matter or improving spring weed suppression. Start out by testing a cover crop on a single field, and expand as you gain management experience.