Cover crops are an integral tool in preserving and increasing soil productivity of Illinois’ grain cropping systems. The benefits of cover crops are numerous, including but not limited to stewardship of soil and water resources, weed suppression, and nutrient retention.

One of the barriers to incorporating cover crops into corn and soybean systems is timely planting, which occurs during the midst of the fall grain harvest season. Furthermore, many cover crop species are not well-researched. The ideal planting dates and survivability across the wide range of weather conditions across the state are still largely unknown, or not well documented. The goal of this project is to evaluate the performance of different common cover crops prior to and after soybean in the crop rotation at different fall planting dates and seeding rates across Illinois. With this data, regional recommendations can be refined to provide more detailed information on the relationship of planting date, winter survivability, and resulting spring stand of various cover crops. Furthermore, this data will improve seeding rate adjustment recommendations based on planting date and region to help producers achieve optimal performance of their cover crop.

To understand more about optimal cover cropping strategies in a soybean/corn rotation, Illinois Extension will conduct two research trials at each of the following locations: 1) Northern Illinois sites (Highland Community College, Joliet Junior College, and/or Illinois Valley Community College); 2) Northwest Illinois Agriculture Research & Demonstration Center, Monmouth; 3) Orr Agricultural Research and Demonstration Center, Baylis; 4) Belleville Research Center, Belleville; and 5) Ewing Demonstration Center, Ewing.

The two research trials will focus on:

1)The effect of cereal rye planting dates, seeding rates, and termination timing on cover crop biomass, soybean performance, and yield.

This replicated, strip trial would evaluate the performance of one commonly available cereal rye variety no-till drilled at 30, 60, 90 and 120 lbs./A into corn stubble at an early, mid, and late planting date about 3-4 weeks apart between late-September and early-November ahead of a no-till soybean crop the following year. Two different termination timings will be evaluated: 18”-24” cereal rye (2-3 weeks before planting) and mature cereal rye terminated at planting.

Data will be collected on cereal rye biomass by taking a dry weight of biomass subsamples collected for each seeding rate and planting date and at each termination timing. The nutrient content of biomass samples from each termination timing and planting date will also be analyzed. Soybean stand and growth progress will be monitored, and yield data will be collected, along with pictures, videos, and imagery to illustrate the project treatments.

The goal of this research is to determine the relationship between seeding rate and planting date on cereal rye stand quality and biomass production to better understand how to prescribe different seeding rates based on planting date and region to achieve a desired level of biomass. Also, this research will increase understanding of how these biomass differences influence soybean stand and yield.

2)The effect of clover cover crop species planting date, planted after soybean, on clover biomass and corn performance and yield.

This replicated, strip trial would evaluate the performance of one balansa clover variety and one crimson clover variety no-till drilled into soybean stubble at an early, mid, and late planting date about 3 weeks apart between late-September and late-October ahead of a no-till corn crop the following year.

Data will be collected on cover crop biomass by taking a dry weight and nutrient analysis of biomass subsamples collected and winter survivability for each species and planting date, corn stand and growth progress, and yield, along with pictures, videos, and imagery to illustrate the project treatments.

The goal of this research is to determine the optimal date window for these clovers across the state for successful winter survivability and biomass production and performance and yield of the following corn crop.

The data from these two trials from five locations across the state will produce a robust data set and knowledge of the best utilization of these cover crops throughout Illinois. Illinois Extension intends to apply for a second year of funding to replicate this research across a second growing season to help understand how the unique weather of each growing season influences these practices within the typical corn-soybean system in Illinois.

The goal is to utilize this data to validate and potentially expand farmers’ confidence in the successful cover crop planting window, seeding rate, and termination timing. These two trials together will help refine how to best manage and maximize a cover crop system both before and after a soybean crop in a soybean/corn rotation. Farmers are always challenged with workload during the harvest season; with better data on planting date performance, they can prioritize cover crop planting at the appropriate time to ensure a successful stand. This information will expand knowledge of cover crop performance across the state, allowing farmers to increase success with cover crops and be able to make more educated decisions on when to plant, how much seed to plant, and when to terminate.

Outreach to farmers will be through online video tours throughout the growing season, field days at each site, farmer meeting presentations, and factsheet summaries of results. The data will also be integrated into the Midwest Cover Crops Council Cover Crop Selector Tool which advises on location specific planting dates for different cover crop species. This tool is utilized by many farmers, crop advisors, and the Natural Resources Conservation Service to guide planting recommendations.

The goal is to utilize this data to validate and potentially expand farmers’ confidence in the successful cover crop planting window, seeding rate, and termination timing. These two trials together will help refine how to best manage and maximize a cover crop system both before and after a soybean crop in a soybean/corn rotation. Farmers are always challenged with workload during the harvest season; with better data on planting date performance, they can prioritize cover crop planting at the appropriate time to ensure a successful stand. This information will expand knowledge of cover crop performance across the state, allowing farmers to increase success with cover crops and be able to make more educated decisions on when to plant, how much seed to plant, and when to terminate.