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Wyoming big Sagebrush (Artemisia tridentata ssp. wyomingensis) rangelands across Nevada's various regions, major land resource areas (MLRA), ecological sites, and elevation zones have been mowed for fuels management. Shrub mowing can promote healthy and more resilient, Wyoming big sagebrush plant communities that are less flammable and less likely to transition to a state dominated by exotics following wildfire.  Or, mowing can favor exotic and highly flammable vegetation.  Responses vary by geographic location (p<0.05). We tested hypotheses across northern and central Nevada by analyzing soil surface and vegetation cover data from 76 unmowed and adjacent sites mowed between 2001 and 2010.  Cheatgrass (Bromus tectorum) and exotic forb responses were negatively correlated with elevation and were not a problem above 6000 feet. Bare soil decreased (mowed minus unmowed) most and cheatgrass increased most in Northwest Nevada and the Malheur High Plateau and Humboldt Area MLRAs (23 & 24). Sagebrush cover decreased most in Northeast Nevada and Owyhee High Plateau MLRA (25).  Exotic forbs increased most in Northwest Nevada and the Humboldt Area MLRA (24). In Northwest Nevada (MLRA 23), with a lower proportion of summer precipitation, cheatgrass and exotic forb increases were greater and they correlated with the relative cover of sagebrush. Native or perennial grass increases correlated with unmowed cover of sagebrush at low elevations and in northeast Nevada (MLRA 25). Litter increased more in the loamy 8-10 than either the drought loam 8-10 or loamy 10-14 ecological sites. Differing responses by geographic area suggest why different mowing studies may show conflicting results.