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The competitive exclusion principle states that species competing for the same limiting resource cannot coexist. This contributes to the successful application of seeding and establishing an intact perennial grass community that resists invasion by cheatgrass (Bromus tectorum). Water and nitrogen are known limited resources in Great Basin ecosystems.� Observations of variability of cheatgrasss suppression or resistance to cheatgrass invasion during wet and dry years indicate soil moisture as a driving factor for resistance to invasion. We monitored perennial grass dominated communities where cheatgrass suppression was observed and the transition to cheatgrass dominance when the perennial grass was removed. �We measured soil moisture and available nitrogen during this transition and the effect that seedbed litter had on cheatgrass invasion after perennial grass removal. �Cheatgrass growth, density and seed banks were measured in healthy, robust and intact perennial grass communities and where the perennial grass was experimentally removed for comparison. We found a threefold increase in cheatgrass biomass when the competing perennial grass was removed (cheatgrass biomass lbs/acre = 108lb vs. 327lb). This increase has dramatic management implications for wildfire fuels management at the landscape level as cheatrgass biomass provides the fine fuels that increase the chance, rate and spread of wildfires in the Great Basin.