Influence of rye/oat cover crop in a two-year soybean production system

As the cost of corn (Zea mays L.) production increases, some farmers find continuous soybean [Glycine max (L.) Merr.] to be more profitable than corn-soybean rotation. However, a grass cover crop could help diversify the cropping system. The study objectives were to evaluate planting date and termination timing of a rye (Secale cereale L.)/oat (Avena sativa L.) cover crop mix on cover crop biomass and soybean disease, insects, slugs, and grain yield within a 2-yr soybean production system. Field trials were conducted in 2018 and 2019 at two locations in Ohio (northwestern and western). The main plot factor was cover crop planting date (September through October) and the subplot factor was cover crop termination timing (2 and 4 wk prior to soybean planting). Cover crop planting date and termination timing had little influence on soybean diseases and insects. Soybean grain yield was influenced by cover crop termination timing at the northwestern location. In 2018, soybean yield was 4% greater when the preceding cover crop was terminated late and in the control (no cover crop) compared to early cover crop termination. The following year, soybean yield was 8% greater when the cover crop was terminated late compared to early termination and the control. At the western location, there was no impact of cover crop termination timing on yield. Late-terminated cover crops had a positive effect or no effect on yield of the following soybean crop.