Much of this region has been glaciated. View is westward up the east front of the Sierra Nevada. Prevailing west winds influence climatic conditions for the whole region. On higher slopes, digger pine and blue oak dominate, forming typical open or woodland stands. Most of the low hills are covered by close-growing evergreen scrub, or chaparral, in which buckbrush and manzanita predominate.
Several oaks are common associates.
Dense chaparral communities of manzanita, buckbrush, and buckthorn may appear after fire, sometimes persisting for years. Within the Sierran rain shadow, on the dry eastern slopes, Jeffrey pine replaces ponderosa pine. At lower elevations, pine forests are replaced by sagebrush-pinyon forest, part of the Intermountain Desert Province. Mountain hemlock, California red fir, lodgepole pine, western white pine, and whitebark pine are important. Lodgepole pine is said to have climax characteristics near the upper limits of this zone.