||Switchgrass (Panicum virgatum), a native warm-season grass often used in wildlife habitat plantings, has the potential as a bioenergy crop. Bioenergy switchgrass are typically monoculture stands, harvested annually, and managed for maximum yield, which may impact the wildlife habitat quality. Our objective is to investigate small mammal populations in bioenergy switchgrass compared to cool-season grass hay and corn (Zea mays) fields (no‐till and conventional till systems). In 2009, 4 three‐night trapping sessions were conducted at 4 locations in Kentucky using Sherman livetraps. Trapping sessions occurred in April/May before first hay harvest (spring), July/August (mid-summer), September/October before switchgrass and corn harvest (late-summer), and December after harvest (fall). Small mammal relative abundance was calculated using a capture per unit effort (CPUE) index (per 100 trapnights). Six mammalian species were recorded: Peromyscus leucopus, P. maniculatus, Mus musculus, Blarina brevicauda, Microtus ochrogaster, and M. pennsylvanicus. Microtus species were classified as Microtus spp. due to difficulties in field identification. All species were recorded in switchgrass and hayfields, while B. brevicauda and Microtus spp. were not found in corn. Chronological CPUE indexes were 5.32, 18.52, 30.05, and 18.61 in switchgrass; 3.06, 22.45, 11.11, and 3.06 in corn; and 2.45, 2.55, 3.79, and 4.72 in hay. Relative abundance in switchgrass and corn were higher than hay in mid-summer, and switchgrass was highest in late-summer. Relative abundance of no-till corn was higher than conventional till corn during all trapping sessions except spring. In conclusion, time of year and management practices (crop species, tillage system, and harvest regime) influence small mammal relative abundance and species richness.