The Red Hills are vegetated mostly by a foothill pine-buckbrush chaparral/woodland. Virtually the only tree species in the Red Hills is Foothill pine (Pinus sabiniana), which is found throughout the Red Hills in low densities. Buckbrush (Ceanothus cuneatus) comprises a majority of the shrub cover. Other shrubs include Toyon (Heteromeles arbutifolia), Coffee berry (Rhamnus californica tomentella), Chamise (Adenostoma fasciculatum), Hollyleaf redberry (Rhamnus crocea ilicifolia), California yerba santa (Eriodictyon californicum), and Manzanitas (Arctostaphylos spp.).