The flora of this ecoregion also includes tree species such as Gray or foothill pine ("Pinus sabiniana"), Scrub oak ("Quercus dumosa"), California buckeye ("Aesculus californica"), the rare Gowen cypress ("Cupressus goveniana)", the rare Monterey cypress ("Cupressus macrocarpa"), and a wealth of endemic plant species, including the extremely rare San Gabriel Mountain liveforever ("Dudlea densiflora"), Catalina mahogany ("Cercocarpus traskiae"), and the threatened most beautiful jewel-flower ("Streptanthus albidus" ssp.