Overseeding Annual Ryegrass and Cereal Rye into Soybean as Part of a Multifunctional Cropping System: I. Grain Crop Yields, Winter Annual Weed Cover, and Residue After Planting

Abstract

Annual ryegrass (Lolium multiflorum Lam.) and cereal rye (Secale cereale L.) are two forages that fit well into mixed row-crop/livestock operations. They can be used both as a cover crop and as a source of winter pasture. However, few studies have investigated the potential to integrate these forages into a soybean [Glycine max (L.) Merrill]-winter pasture-corn (Zea mays L.) rotation. This experiment was conducted with each of these cover crop/forage species overseeded into soybean at different stages of development, and subsequently harvested as forage throughout the winter. Corn was grown as a subsequent crop. Soybean yield was not altered by overseeding annual ryegrass or cereal rye. The overseeded treatments had at least 60% more residue cover and at least 70% less weed cover compared to the control plots. In Year 2, corn yield was lower when annual ryegrass was overseeded regardless of soybean developmental stage and when cereal rye was overseeded at soybean development stage R 6.5. An extended period of low rainfall during the summer of 2005 strongly influenced Year 2 corn yields. Our results demonstrate that mixed row-crop/livestock operations in the lower Midwest could use cereal rye or annual ryegrass as a cover crop but subsequent corn yield can be reduced in years where soil moisture is limiting.