Forming a hiatus between the Pacific and the desert slope is the Sierran Biotic Province consisting of coniferous forests on the crest of the range. The chipmunk (Eutamias speciosus speciosus) and the introduced black bear (Ursus americanus californiensis) are the only two mammals which can be considered typical of this area. On the higher peaks of the range, such as Mount San Antonio and Mount Baden Powell, the Canadian Life-zone is represented by certain boreal plants.
At scattered points along the crest of the range and on the desert slope, the Nevadan Biotic Province is represented by the sagebrush scrub association. No mammals can be considered typical of this region.
The Southern Desert Biotic Province occurs below 6000 feet elevation on the interior slope of the range, and markedly influences the mammal fauna of this slope. Twenty-one species of mammals are typical of this Province.
Scientific and Common Names of Plants Mentioned in This Report
| Pinus lambertiana | Sugar Pine |
| P. monophylla | One-leaf Pinyon |
| P. ponderosa | Yellow Pine |
| P. contorta | Lodge-pole Pine |
| Pseudotsuga macrocarpa | Big-cone Spruce |
| Abies concolor | White Fir |
| Libocedrus decurrens | Incense-Cedar |
| Juniperus californica | Juniper |
| Ephedra sp. | Desert-Tea |
| Bromus sp. | Brome Grass |
| Yucca Whipplei | Spanish Bayonet |
| Y. brevifolia | Joshua Tree |
| Salix sp. | Willow |
| Alnus rhombifolia | Alder |
| Castanopsis sempervirens | Chinquapin |
| Quercus Kelloggii | California Black Oak |
| Q. agrifolia | California Live Oak |
| Q. dumosa | Scrub Oak |
| Eriogonum fasciculatum | California Buckwheat |
| Umbellularia californica | Bay, California-laurel |
| Ribes nevadense | Gooseberry |
| R. indecorum | Currant |
| R. Roezlii | Currant |
| Plantanus racemosa | Sycamore |
| Rubus vitifolius | Western Blackberry |
| Cercocarpus ledifolius | Mountain Mahogany |
| C. betuloides | Mountain Mahogany |
| Adenostoma fasciculatum | Greasewood |
| Purshia glandulosa | Antelope-brush |
| Prunus virginiana | Choke Cherry |
| P. ilicifolia | Holly-leaved Cherry |
| Larrea divaricata | Creosote Bush |
| Rhus diversiloba | Poisonoak |
| R. trilobata | Squaw Bush |
| R. laurina | Laurel Sumac |
| R. integrifolia | Lemonadeberry |
| R. ovata | Sugarbush |
| Rhamnus crocea | Buckthorn |
| Ceanothus sp. | Lilac |
| C. cordulatus | Snow-brush |
| Fremontia californica | California Slippery-elm |
| Opuntia occidentalis | Prickly-pear |
| Arctostaphylos sp. | Manzanita |
| Salvia mellifera | Black Sage |
| S. apiana | White Sage |
| Lycium Andersonii | Box-thorn |
| Haplopappus squarosus | |
| Chrysothamnus nauseosus | Rabbitbrush |
| Baccharis sp. | Mule Fat |
| Franseria dumosa | Burroweed |
| Artemisia tridentata | Basin Sagebrush |
| A. californica | Coastal Sagebrush |
| Lepidospartum squamatum | Scale-broom |
| L. latisquamatum | Scale-broom |
| Tetradymia spinosa | Cotton-thorn |
Coastal Sage Scrub Association
Major Plants
Artemisia californica
Salvia apiana
Salvia mellifera
Eriogonum fasciculatum
Rhus integrifolia
Opuntia occidentalis
Haploppapus squarrosus
This association is restricted to the Pacific base of the range, is typical on the alluvium at the bases of the coastal foothills, and usually grades into the chaparral at about 1800 feet elevation. When seen from above, the rather level terrain of the association is broken sharply at the mouths of canyons by dry washes, and is limited below, to the south, by cultivated land. The coastal sagebrush is the most characteristic plant of this association, occurring in all undisturbed parts of the area.