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Short-term post-fire field studies have shown native shrub cover in chaparral ecosystems is negatively associated with introduced forb and graminoid cover, which is influenced by burn severity, elevation, aspect, and climate. Previous long-term remote sensing studies found differences in shrub recovery depend on climate, while short-term remote sensing studies found differences in recovery depend on burn conditions which were influenced by weather.� The 2003 Old and Simi fires in southern California burned across a gradient of vegetation types, elevation, aspect, and climate. We sought to understand the role of native shrubs in post-fire recovery across biotic and abiotic variables, linking long-term field and remote sensing data for these two fires. Using Normalized Burn Ratio (NBR) as an indicator of green vegetation derived from 1984-2016 Landsat imagery, we determined that sites burned at moderate and high burn severity have not returned to pre-fire levels of greenness, whereas sites that burned at low burn severity have. For ground reference, we estimated percent cover of functional groups in 2004 and 2015 at nested sampling sites distributed across gradients of burn severity, elevation, aspect, and time. Using non-metric multidimensional scaling, mixed effects models, and ANOVAs, we found that by year twelve, burn severity was no longer a significant predictor of native shrub cover but remained predictive for forbs and graminoid cover. This supports other long-term studies finding no or positive fire effects on shrubs, but negative or no fire effects on other functional groups over time. We also found high shrub cover to be a significant predictor of low introduced richness and high native cover, suggesting native shrubs may competitively exclude introduced species and facilitate native species.