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Treatments to reduce shrub cover are commonly implemented on the assumption that they will increase herbaceous perennial production. However, these treatments can have variable effects on shrub cover, herbaceous perennials, and non-target herbaceous annuals, and the factors mediating this variability are not well understood. In the sagebrush rangelands of the Intermountain West, the need to understand the outcomes of shrub reduction treatments has gained importance as management focuses on the needs of sensitive species such as sage-grouse. We used long-term data from Utah�s Watershed Restoration Initiative (WRI) project (initiated in 2003) to assess short-term (1-5 years post-treatment) and long-term (6-12 years post-treatment) responses of sagebrush plant communities to five shrub reduction treatments at sites across Utah (n=96 total): wildfire with and without post-fire seeding, pipe harrow with one or two passes, and aerator. We used moderator analyses to investigate the effects of treatments on changes in cover of sagebrush (Artemisia tridentata), grasses, and forbs within each of three sagebrush sub-species communities. Shrub reduction treatments only increased perennial grasses substantially in�A. tridentata�ssp.�wyomingensis�sites (all treatments) and in ssp.�vaseyana�sites that were seeded after fire. Perennial forb cover increased in all treatments (except aerator) in the short-term, but these effects only persisted in the long-term in ssp.�Wyomingensis�sites. Annual grasses (largely cheatgrass,�Bromus tectorum) increased in all treatments in ssp.�vaseyana�sites but stayed constant or decreased (especially in sites seeded after fire) in ssp.�Wyomingensis�and ssp.�tridentata�sites. In contrast to these shrub community-dependent effects of treatment, site factors (elevation, slope, and precipitation) rarely had significant effects on cover responses to treatments. Although these results provide some evidence that perennial cover increases as a result of shrub reduction, they also illustrate that this outcome depends on sagebrush community and does not persist in the long-term.