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Sagebrush steppe ecosystems are one of the most widespread but endangered ecosystems in North America. A diverse array of human-related stressors has gradually compromised these ecosystems’ resilience to disturbance and invasion by cheatgrass. The role of the foundational shrub Artemisia as a driver of herbaceous community structure and dynamics during this degradation process is poorly understood. Many of the individual factors driving cheatgrass invasions are well documented. However a predictive understanding of the relative importance of complex, interacting factors in the causal network of simultaneously occurring processes determining invasibility has proven elusive. I examined these issues at the landscape level across 75 sites capturing a range of soil and landscape properties and cattle grazing levels similar to those found across the Great Basin.