Cover crop can offset negative effects of corn silage harvest on soils in a corn silage–soybean rotation

Abstract Harvesting corn ( Zea mays L.) as silage is an important component of many livestock operations but can lead to soil degradation without support practices like cover crops (CCs). However, long‐term research investigating the effects of such combination of practices on soils is minimal. We assessed (1) the impact of a winter rye ( Secale cereale L.) CC following corn silage (CS + CC) on dynamic soil biological, chemical, and physical health indicators in a no‐till corn–soybean ( Glycine max L.) rotation compared with corn silage no cover crop (CS + NCC) after 21 years of management, (2) if soil health under CS + CC was similar to corn grain no CC (CG + NCC), and (3) whether any effects of CS + NCC existed following both rotation phases in a US Midwest Mollisol. CS + CC increased soil microbial biomass and activity, labile and total C and N concentrations, and aggregation compared with CS + NCC due to greater biomass input. In both rotation phases, CS + CC had no effect on most biological and chemical properties compared with CG + NCC. As expected, CS + NCC negatively affected soil biological properties and organic carbon and total nitrogen concentrations compared with CG + NCC, which persisted in both crop phases. Treatment effects on soil properties were few below 5 cm. The CC did not affect crop yields across years, but crop yields were positively correlated with some soil properties. Overall, a winter rye CC following corn silage can maintain many soil properties at levels similar to corn grain without negatively impacting yields, unlike CS + NCC, in this US Midwest Mollisol.