Database Research Summaries
2018 Implementation of Cover Crop in NE Corn & Soybean Cropping Systems

calendar_today Year of Research: 2018
update Posted On: 12/04/2019
group Roger Elmore (Principal Investigator, University of Nebraska)
bookmark Nebraska Soybean Board

Research Focus

The focus of this project is to explore potential sustainable corn and soybean production systems in Nebraska.


  • Explore corn-soybean production systems that incorporate cover crops.
  • Determine the feasibility of using cover crops, seeded no-till in soybean and corn cropping systems.
  • Examine cover crop performance at four Nebraska sites – both rainfed (Concord & Mead) and irrigated (Clay Center & Brule).
  • Assess the impacts of single and multi-species cover crop mixes planted with two
    methods and timings on corn yield, soil properties, and economic return when managed under no-till soybean/corn and continuous corn across four representative locations in Nebraska.


  1. Cover crops are best suited for the Eastern and South-Central parts of Nebraska. Cover crops had similar productivity at the eastern and south-central sites, but did not establish at the western site.
  2. Cover crops did not reduce soil water. Soil water under diverse mix plots was not significantly lower than soil water under control plots most times, and where differences existed, they were small. However, the diverse mix was less productive than rye and soil water was not measured continuously.
  3. Rye has the potential to reduce soil nitrate losses and thus prevent pollution of ground and surface water. In most site years, rye and rye mixes significantly lowered soil nitrate in the 0-2 and 2-8″ depth in the spring (sampled just before cover crops were terminated). Reductions were larger at the south-central site where soil nitrate was higher since soils warmed up faster in the spring.
  4. Cover crops reduced corn and soybean yields in about half of the site years. On average, soybean yields were reduced by6.5% and corn yields by 10.5%. Rye caused most yield reductions, possibly due to N immobilization. Legumes that escaped termination and became weeds also impacted yields, especially in soybean. Corn yields were increased in one year by rye, probably because rye mulch reduced evaporation.


  • Researchers measured cover crop biomass emergence and production to determine cover crop productivity and evaluate cover crop management (species and planting times) to find cover crops suited to Nebraska no-till soybean systems.
  • Researchers measured changes in soil temperature, soil water, soil N and soil physical properties to explain impacts of cover crops on soils and subsequently, crop yields.
  • Information will be transferred in statewide crop production clinics.
  • There will be an online presence through CropWatch (2016, 2017, 2018), and NebGuides will be published.

For more information about this research project, please visit the National Soybean Checkoff Research Database.

Funded in part by the soybean checkoff.