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Effects of burn severity on post-fire non-native plant invasion is of great concern to managers and researchers, especially given predicted increases in large, high severity fires. However, fewer studies have focused on long-term (>10 year) non-native plant establishment and persistence. We analyzed non-native plant cover 12-13 years post-fire to determine the effect of burn severity on non-native plants. We compared percent cover of non-native plant species between wildfires in southern California chaparral (Old and Simi Fires of 2003) and dry ponderosa pine forests in central Colorado (Hayman Fire of 2002). Preliminary analysis of the 12- or 13-year post-fire data show significantly higher non-native plant cover in the high severity burn (TukeyHSD, p=0.02) in dry ponderosa, but no significant differences between burn severity classes for chaparral (p=0.15) where non-native species were more abundant regardless of burn severity. Non-native species of the California fires include Bromus tectorum, Poa pratensis and Erodium cicutarium. For the Colorado fire, non-native species include Taraxacum officinale, Verbascum thapsus and Bromus tectorum. While non-native species response to fire is clearly ecosystem specific, our data indicate that dry ponderosa forest types burned at high severity may be more susceptible to non-native plant invasion than those burned at lower severities. Therefore, mitigation of high severity burns should be a high priority of managers in dry ponderosa pine ecosystems where invasive plant establishment is a concern.