Investigating the potential of winter camelina to mitigate nitrogen immobilization and nitrate leaching as a cover crop for the Upper Midwest

Commodities

Practices

Winter cereals, especially cereal rye, remain the sole cover crop option for farmers in the Upper Midwest within the predominant corn and soybean rotations. While there are many conservation benefits–reducing erosion, nitrogen scavenging, weed control–of cereal rye, its rapid spring growth immobilizes nitrogen, which can reduce corn yield. Winter camelina, which has a similar planting window to cereal rye, has the potential to strike a compromise between the conservation benefits of our more conventional cover crops while minimizing the yield drag on the subsequent corn crop. In order to investigate this potential, we will use a novel, easy to deploy method of measuring cumulative nitrate loss using resin lysimeters to compare between treatments of winter camelina, winter rye, and winter fallow following soybeans on 4 farms. Furthermore, an additional treatment of a drone seeding of winter camelina prior to leaf drop in soybean will evaluate how new technology can facilitate earlier seeding and affect conservation benefits of these cover crops. Results will be worked into fact sheets and Extension recommendations as well as presented at field days and conferences.

1. Quantify nitrate leaching during winter of winter camelina vs. winter cereal rye vs. fallow using resin lysimeters.
2. Measure nitrogen available to corn and subsequent yield in treatment plots to determine if winter camelina can mitigate cover crop yield drag seen in corn following winter rye.
3. Provide outreach on project results through Extension articles, field days, and conference presentations. 
4. Evaluate feasibility of using resin lysimeters as a tool for measuring cumulative nitrate leaching in on-farm research.
5. As a result, increase farmer understanding and options for cover crop management to reduce nitrogen loss and immobilization.