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The increasing presence of wildfire on sagebrush landscapes is driving widespread loss of critical wildlife habitat and greatly diminished grazing resources.� Over much of the sagebrush region, these changes are associated with both the loss of sagebrush, as well as the increased post-fire presence of exotic annual grasses. �These annual species increase fine fuel continuity and the probability of fire ignition and spread.� Mature perennial bunchgrasses effectively compete with exotic annual grasses and can reduce spread and persistence of these species, but bunchgrasses are often killed by fire.� Much of the effort to mitigate the exotic annual grass problem has centered on post-fire restoration of perennial bunchgrasses, however, post-fire seeding of perennial bunchgrasses often fails, particularly on warm and dry sites that are prone to annual grass invasion.� Pre-fire fuels management may help to reduce both perennial bunchgrass mortality during the fire, and the need for restoration following fire.� In recent field research, we have documented that perennial bunchgrass mortality in wildfire can be high (up to 60%) and that most bunchgrass mortality during wildfire is associated with close proximity to sagebrush fuels.� Follow-up research has confirmed that sagebrush fuels produce very high heat output during combustion and that combustion of shrub fuels is the primary factor associated with generating heat loads high enough to kill perennial bunchgrasses.� Heat output from grasses is comparatively low, and insufficient to cause perennial bunchgrass mortality.� However, grass fuels serve as a vector to carry fire from shrub to shrub and reducing grass fuels can decrease shrub combustion and fire behavior measures. �Overall, recent data suggest that preemptive manipulation of both shrub and grass fuels has the potential to reduce mortality of perennial bunchgrasses during fire, thus increasing post-fire resistance to annual grass invasion.