The long term dynamics of coyote brush invasion in a type-converted landscape of Southern California

Abstract

Coyote brush (Baccharis pilularis) is a native shrub common to the coastal sage scrub (CSS) habitat of California and often appears in a complex mosaic with other vegetation types including grasslands. Both CSS and California grasslands are threatened habitats, where restorations of type-converted landscapes are often burdened by the persistent dominance of non-native annual grasses. However, coyote brush has been documented periodically invading grasslands, resulting in a change of state from grassland to shrubland. This study investigates the long-term dynamics of coyote brush invasion in a type-converted landscape of Southern California. Stands of expanding coyote brush were transected to identify species composition along a spatial and temporal continuum. Results show that following initial invasion, non-native species are replaced by not only coyote brush, but also several other noteworthy native species. This study shows that in Southern California, coyote brush invasion of type-converted landscapes leads to increased native diversity that includes native grasses.