The Iowa Nutrient Reduction Strategy released a report in May 2013 that lists annual cover crops as the most influential practice for reducing nitrogen loss from fields that are in continuous row crop production.
The Iowa Soybean Association On-Farm Network® is conducting research to evaluate various cover crops. Earlier this year, Case IH provided a Puma® tractor and Precision Disk 500T® to plant cover crop replicated strip trials on a few prevented-planting fields. Research results will be known next year.
A number of different seed blends, including those with tillage radish, are being studied.
The On-Farm Network suggests the following steps for establishing a good cover crop stand:
- Timely seeding. In Iowa, seeding should be done in a standing crop of corn or soybeans, just as the leaves are beginning to turn, to allow enough sunlight to germinate.
- Proper seed variety or mixture. There are a number of cover crops and mixes to consider.
- Seeding method. There are advantages to both aerial seeding and drilling cover crops. Seeding with a drill usually results in better establishment but the seeding window is less than aerial.
- Seeding rate. Thin stands may not provide necessary soil protection over winter. Aerial seeding requires a higher seeding rate than if the crop is drilled.
If you’ve used cover crops, we invite you to share some of the learning from your experience.
