Use of cover crops in intensive row-crop agriculture has dramatically increased over the last decade. Cover crops provide vegetative cover and forage that may support more diverse and abundant rodent communities than those found in conventional row-crop agroecosystems. However, increasing vole populations can lead to depredation of the soybean (Glycine max) commodity crop. We tested for selection of 13 commonly planted cover crops and 4-5 additional benchmark species by meadow (Microtus pennsylvanicus) and prairie (M. ochrogaster) voles using cafeteria-style feeding trials conducted in semi-natural outdoor enclosures. Red clover (Trifolium pratense), alfalfa (Medicago sativa), and hairy vetch (Vicia villosa) were commonly preferred among vole species, and canola (Brassica napus) was avoided. Meadow and prairie voles consistently chose or avoided highly and minimally preferred species, respectively, but were more variable in choosing moderately preferred species. Consumption scores were negatively associated with the number of plants offered in a trial, and the relationship was stronger for males than females. The interaction of protein and fiber content of plants, and vole identity included as a random effect, were also important in predicting score probability for both vole species. Identifying minimally preferred plants and factors that influence selection may allow farmers to manage cover-cropped soybean fields to discourage immigration of small mammals into fields, thus reducing negative consequences that might otherwise limit future adoption of a valuable soil conservation practice.