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Deserts of North America are experiencing larger wildfires at shorter intervals. This increased fire frequency is attributed to increasing temperatures, droughts, and fuel buildup from non-native annual grasses Bromus rubens and Bromus tectorum. The transition from desert shrub land to annual grassland following fire may be mediated by small mammals.  But the specific influence of small mammals on the reestablishment of native plant communities has not been well quantified post-fire. To measure these influences we established long-term studies at sites in the Mojave and Great Basin Deserts.  These cross-factorial experiments examine the main and interactive effects of fire and small mammals. The experiment includes burned and unburned treatments with small mammal exclusion or inclusion.  Plant cover and density have been collected each year. We have evaluated the responses of the plant communities to fire and small mammals and have found strong bottom-up responses of fire in increasing densities of Erodium cicutarium, Schismus arabicus, and Ceratocephala testiculata. The presence of small mammals strongly decreases the invasive plants Bromus rubens and Halogeton glomeratus. These plant community responses are creating intermediate vegetation states as either a fire prone or fire resistant community.  Small mammal abundance post-fire shifts the dominance of the invasive species to create these intermediate vegetation states.