We assessed differential use of roadside fencerows and contiguous pastures by small mammals in southeastern Oklahoma during September 1991, February 1992, and May 1992. Eight species of rodents and shrews were represented in 338 individuals captured; however, the four most common species comprised 96% of all captures (Sigmodon hispidus, 64% of all captures; Peromyscus maniculatus, 13%; Mus ... [Show full abstract] musculus, 12%; and Reithrodontomys fulvescens, 7%). No seasonal differences in use of fencerows and pastures were found for total captures of any of these four species. Sigmodon hispidus, M. musculus, and R. fulvescens selectively used fencerows; P. maniculatus chose pastures. No differences between males and females in use of fencerows and pastures were noted for any species. However, significant differences were found in use of fencerows and pastures among different size classes of S. hispidus; small males (<60 and 60-110 g) and females <60 g and > 110 g were significantly more abundant in fencerows than pastures.