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The enzyme status of soil influences mineralization kinetics, and thus, the supply of nutrients to plants. We quantified urease, asparaginase, glutaminase, phosphatase, and arylsulfatase activity in a sagebrush/grass ecosystem northeast of Reno, NV. Enzyme activity was evaluated by depth (0 to 5 cm, 5 to 10 cm, 10 to 20 cm), microsite (sagebrush, crested wheatgrass, cheatgrass, cryptogamic crust in shrub interspace, noncryptogamic crust in shrub interspace), and treatment (grazed and ungrazed). For most enzymes evaluated, there was a significant depth x microsite interaction. In general, enzyme activity declined with depth. Moreover, the noncryptogamic interspace microsite often had the lowest enzyme activity among the other microsites. Depending on soil depth and microsite, the grazing treatment significantly reduced urease, asparaginase, and alkaline phosphatase activity compared to the ungrazed treatment. Enzyme activity is an important soil attribute and may serve as a robust measure of soil health.