Planting cereal rye before soybeans has become the most widely used cover crop and cash crop combination today. It is readily chosen because of its hardiness, ease of establishment, low cost, multiple planting methods and wide planting window in the fall. Cover crops, like cereal rye, provide many benefits for the upcoming soybean crop such as weed suppression, insect management, disease management, soil erosion prevention, nutrient scavenging and nutrient cycling.
But the key to being successful is not only determining your goals when planting cereal rye ahead of soybeans, but to also properly evaluate the cover crop stand and its tillering. In some years, the seeding rate of cereal rye is not considered as important as the planting date and the weather.
For example, cereal rye planted at a rate of 45 pounds per acre at the end of September, with a good fall growing season, can be thicker than if it were planted the 1st week of November at a rate of 80 pounds to the acre. It is for this reason that we must evaluate our cereal rye stand in the spring to determine when you should terminate the growing cover crop. While cereal rye does tiller less than wheat, it should still be evaluated to determine tillering and final thickness of the stand. Use this information to decide seeding rates for the next fall.
Cereal rye stand density evaluation: Determine how many tillers and potential stems are in a 3-foot by 3-foot area. If this number exceeds 120, then early termination should be considered, and the termination timing will depend upon your goals for the cover crop.
Termination timing: After evaluating your stand, cereal rye should be terminated around 8-inches in height or immediately before or after soybean planting. But keep in mind, termination anywhere within this timeframe has the potential to cause planting delays due to excess soil moisture and the potential for poor stand establishment.
Other considerations: When evaluating the cereal rye stand in the spring, scout for pests such as voles and slugs that relish the cover crop microenvironment. This scouting information can help determine proper termination timing of the cover crop. For example, an early presence of pests would indicate early termination of the cover crop.
Today most planters, air seeders and drills do an excellent job of pushing over cereal rye when seeding cereal rye. This provides better weed management, improved soil moisture retention, faster nutrient cycling, and quicker breakdown of the crop residue. When planting soybeans into tall cereal rye (3 feet or taller) with 30-inch row planters, one should consider additional methods to lay over cereal rye. A rolling basket or roller crimper can also be used to lay down the cereal rye and this can help increase the amount of light available to the soybean plant during the growing season.
With the proper management, planting a cover crop ahead of soybeans can be very beneficial and help you meet your goals. Cereal rye is a good cover crop to begin with because it is so easy to establish and an excellent cover crop.
Reynolds joined American Farmland Trust in January 2017 as the Natural Resource Conservationist. He is responsible for working with the many partners in the Upper Macoupin Creek and Vermillion Headwaters Watersheds. Reynolds coordinates activities with farmers and landowners that improve water quality and soil health, enhance nutrient efficiency, utilize conservation cropping systems and meet the goals of Illinois’ Nutrient Loss Reduction Strategy. In addition to being a CCA, he holds specialty certifications from the American Society of Agronomy as a 4R Nutrient Management Specialist and Sustainability specialist. He holds a B.S. in Agronomy and Ag Business from Illinois State University.