class="brd-t2 brd-r">Plant community

Life-zone Slope Californian 1. Coastal sage scrub
2. Southern oak woodland
3. Chaparral Lower Sonoran
Upper Sonoran
Upper Sonoran Pacific
Pacific
Pacific Sierran 4. Yellow pine forest and limited areas of boreal flora Transition Canadian Pacific and Desert Nevadan 5. Sagebrush scrub Transition Upper Sonoran Desert Southern Desert 6. Pinyon-juniper woodland
7. Joshua tree woodland Upper Sonoran
Lower Sonoran Desert
Desert

The Californian Biotic Province dominates the biotic aspect of the coastal slope of the range. Thirty-nine out of the seventy-two mammals recorded from the San Gabriels are typical of this Province. The coastal sage-flats at the Pacific base of the mountains and the vast tracts of chaparral of the coastal slope are included in this Province.

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.

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

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.

There are several habitats within the coastal sage scrub association. These differ from one another chiefly on the basis of soil type. The soil of the rather level sageland in most places is rocky or gravelly, or, as adjacent to washes, it is finely sandy in texture, and supports the major plants of the association. Most of the eroded adobe banks at the bases of the foothills support these same plants, with white sage being the dominant species. Locally, as in damp hollows or cleared areas, there is grassland. Jumbles of boulders, sand, gravel, and steep cutbanks, are characteristic of the channels of dry washes, these areas supporting sparse vegetation. The fauna and flora of the washes are