<p>Biochar and cover crops are often considered to improve soil properties. Yet, how low biochar application rates and multi-species cover crops affect soil properties in the long term (&gt; 10 years) is not well known. We assessed the impact of wood biochar (2.40 Mg ha^− 1 with 701 g kg^-1 C), wood biochar (2.40 Mg ha^− 1) + 168&#xa0;kg N ha^− 1, and cover crop mix on soil properties of a fertile (38 g kg^-1 organic matter concentration) silty clay loam (fine, smectitic, mesic Typic Argiudoll) in a no-till corn-soybean system in the western U.S. Corn Belt after 10 years. Biochar applied once at 2.40 Mg ha^− 1 had no effect on soil properties in the 0–15.2&#xa0;cm soil depth. Cover crop mix increased soil K concentration but did not affect other soil properties. However, while differences were not statistically significant, most soil properties including wet aggregate stability, water content at -33&#xa0;kPa matric potential (field capacity), microbial properties (total microbial biomass, total bacteria, actinomycetes, total fungi, arbuscular mycorrhizal, saprophytes, and protozoa), pH, and concentrations of organic matter, total C, K, and P were numerically larger under biochar than no biochar. These trends suggest that larger than 2.40 Mg biochar ha^− 1 may be needed to detect significant changes in soil properties. Results indicate fertile soils such as Mollisols may not significantly respond to low biochar rates and cover crop mixes even after 10 years, which warrant the need for research on whether these practices are more beneficial in degraded or low-fertility soils.</p>