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Brush management techniques are widely applied on rangelands for multiple objectives; two common objectives are to increase forage production for livestock and to maintain a healthy wildlife habitat.�Our objectives were to determine the effects of previous disturbances and the establishment of exotic grasses on native herbaceous vegetation and small mammal abundance and species richness on a desert scrubland community. The study was conducted in the southern end of the Sonoran Desert in the state of Sonora, M�xico. Three pairs of 2 ha sites were selected for sampling: in each pair of sites, one was previously cleared by mechanical means and seeded with buffelgrass 27 years before and the other did not have previous mechanical disturbance (control). For vegetation sampling, response variables included canopy cover of woody plants, canopy cover of herbaceous plants and species richness; for small mammals, Sherman traps were used to evaluate abundance and species richness. Total canopy cover of herbaceous plants, litter, and bare ground resulted similar between treatments. In terms of relative canopy cover of herbaceous vegetation, results show higher percentage of buffelgrass (80 � 15) on previously disturbed and seeded sites in comparison to the undisturbed treatment (18 � 15); on the other hand, higher percentage of native grasses on the undisturbed sites in comparison to the previously disturbed and seeded treatment with 77% and 18%, respectively. The most abundant specie of small mammals was the Dipodomys merriami for both treatments; five different species of small mammals were found on the previously disturbed and seeded treatment in comparison to four species on the undisturbed sites. The results of the previous mechanical and seeding management practices on the desert scrubland community reflect a dominance of buffelgrass, while in areas with no previous mechanical disturbance is still dominated by native species. There is concern that disturbances associated with mechanical practices could facilitate the invasion of exotic grasses.