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Imazapic is commonly used to manage cheatgrass (Bromus tectorum) on rangelands where cheatgrass-fueled fires threaten sagebrush conservation. However, the amount of herbicide reaching its target site may be reduced via shrub canopy interception. We evaluated two formulations of imazapic � liquid and granular � for cheatgrass control beneath shrub canopies in greenhouse and field studies. In the greenhouse, we applied both imazapic formulations at five preemergent rates to pots seeded with cheatgrass � with and without a sagebrush canopy. Cheatgrass biomass did not differ between formulations (p>0.2) or canopy cover treatments (p>0.6) in the greenhouse. We aerially applied liquid imazapic at 123 g ai�ha-1 and granular imazapic at 135 g ai�ha-1 at four field sites: Hyattville, Pinedale, Saratoga, and Sheridan, WY. We collected cheatgrass biomass beneath shrub canopies and within shrub interspaces at all sites one year after treatment (YAT) and two YAT at Saratoga and Pinedale. Cheatgrass biomass reductions were not observed one YAT at Hyattville or Sheridan for either herbicide formulation (p>0.4). No differences were detected between cheatgrass biomass beneath shrubs or in interspaces one YAT at Saratoga or Pinedale (p>0.68). Herbicide treatment was the only factor affecting cheatgrass biomass one YAT at Saratoga and Pinedale (p<0.05). One YAT at Saratoga, both imazapic formulations similarly reduced cheatgrass biomass, but at Pinedale, the liquid formulation reduced cheatgrass biomass more than the granular. Saratoga was the only site with biomass reduction beneath shrubs for both formulations two YAT (p<0.05). We quantified herbicide deposition at the soil surface at Hyattville and Sheridan during aerial herbicide applications. Liquid imazapic coverage (%) was greater in interspaces than under shrubs (p<0.001). Granular imazapic weight (g�ha-1) was consistent at both sites (p>0.7). Our results indicate that although a granular formulation may provide greater herbicide deposition beneath shrub canopies than liquid, similar reductions in cheatgrass biomass may be achieved.