Agroecosystem Impact of Relay and Double Cropping winter Annual Oilseeds in Corn and Soybean

Many corn and soybean producers have expressed interest in using cover crops in their crop rotations to enhance soil organic matter and reduce soil erosion. However, they have struggled to incorporate cover crops into their rotations because of the difficulty of cover crop establishment, cost of seed, and lack of direct economic return. Researchers at the University of Minnesota are keenly aware of these issues, and are committed to developing new cash cover crop options that have economic potential, but also provide agroecosystem services. The winter oilseed cropping system offers soybean growers new economic opportunities through the additional production of pennycress and camelina protein, for feed and food markets, along with providing oil, for fuel, food, and industrial uses. Recent research findings indicated that the relay and double cropping systems have the potential to increase total yields (i.e. oilseed + soybean yield) up to 50% when compared to a full-season soybean. The over-yielding potential of relay and double cropping winter annual oilseeds with corn and soybean offers growers economic opportunity to make the current corn and soybean rotations more profitable. In addition to yield benefits, current research funded by the Minnesota Soybean Research and Promotion Council and the Forever Green Initiative, is also investigating economic opportunities afforded by the soybean cyst nematode and weed suppression ability of winter oilseeds. Although economic opportunities are very important to the success of this program, it is also vital to investigate the agroecosystem services that including these oilseeds in the rotation may provide. “Evaluating agroecosystem impacts of including winter annual oilseeds in corn and soybean rotations” is proposing to investigate the ability of the winter oilseeds to reduce nitrate leaching and attract pollinators/ beneficial insects early in spring when food sources are scarce in mono-crop systems. Understanding the potential of winter oilseeds to provide these benefits may further incentivize growers to adopt this system.

The foremost learning outcome of this project is to make growers aware of the issues surrounding nitrate leaching and pollinator food scarcity. The project intends to raise awareness to the fact that agriculture is the largest contributor of nitrates into the water supply, and that pollinator health and collapse is in part due to the mono-cropped landscape in which pollinators cannot find an adequate food supply for a long periods of the year.  In addition, the project will investigate solutions for these pressing issues by researching how winter annual oilseeds can reduce nitrate leaching and provide food for pollinators when little else is available. The main action objective of this project is to add value to the cropping system and promote adoption of winter annual oilseed crops by corn and soybean growers across the upper-Midwest.