Abstract The use of cover crop‐based rotational tillage has been proposed as a strategy to reduce tillage and control weeds in organic systems. Termination is a critical part of this system, as incomplete termination of the cover crop can lead to competition for moisture and nutrients with the commodity crop, poor weed suppression, and seed contamination of subsequent crops. The effect of different mechanical termination strategies for cereal rye ( Secale cereale L.) and seeding rate on soybean Glycine max (L.) Merr. population and yield, weed biomass, and volunteer cereal rye growth was assessed. Factorial experiments were conducted on research stations and commercial farms across Wisconsin in 2019, 2020, and 2021, totaling 9‐site years. Soybeans were planted without tillage at rates of 457,000 and 556,000 seeds ha −1 on 76 cm row widths into a cereal rye cover crop that was terminated using one of two commercially available roller crimpers or a sickle bar mower. While both crimping and mowing were found to be effective termination strategies, mowing increased weed biomass while decreasing soybean yields in some site years. Across 7‐site years with the full factorial design (seeding rate was excluded as a factor in 2‐site years), the mowed termination strategy led to 15% lower yields compared to one of the crimpers. This suggests mowing as a termination strategy is likely to be riskier under conditions of low cereal rye biomass and increasing grass weed pressure.
Drewry et al. (2026) studied this question.