Shrublands of the California Floristic Province

California is home to many vegetation types that are dominated by shrubs. In the California Floristic Province (on the cis-montane side of California's major mountain chains) there are three main types.

Northern Coastal Scrub

Northern coastal scrub
Baccharis pilularis in northern coastal scrub.

Northern Coastal Scrub is dominated by evergreen species with soft, evergreen leaves. It occurs primarily along the coast from Monterrey county north. Its main dominant is Baccharis pilularis, or coyote brush. Since it does not occur close to San Bernardino, we will not discuss this shrubland type any further.

Coastal Sage Scrub (= California Sage Scrub)

Coastal Sage Scrub occurs along the coast in the southern part of the state. It is dominated by drought-deciduous shrubs and subshrubs that include various species of sage (Salvia spp.), California sagebrush (Artemisia californica) and California buckwheat (Eriogonum fasciculatum). Because this vegetation type can occur far from the coast (such as at CSUSB), people have begun to call this vegetation "California Sage Scrub", or "CSS" (an abbreviation for both Coastal Sage Scrub and California Sage Scrub). Since the leaves of the dominant shrubs in CSS are very flexible, it has also been called "soft chaparral".

Common dominants of CSS.
Common dominants of CSS.

 

A number of species of CSS are endemic to the California Floristic Province. These endemics include many of the sages (Salvia spp.) and California sagebrush (Artemisia californica).

Geographic distribution of three species of Salvia.
Geographic distribution of three species of Salvia (sage).

Chaparral

Chaparral is sometimes referred to as "hard chaparral". It is dominated by shrub species with hard, evergreen leaves. Examples of species that dominate chaparral in California include scrub oaks, chamise (Adenostoma fasciculatum), various species of manzanita (Arctostaphylos spp.), various species of Ceanothus, and many more (e.g., Rhus spp., Prunus ilicifolia, Heteromeles arbutifolia, etc.).

 

Some dominants of chaparral
Some dominants of chaparral.

 In addition to differences in the characteristics of the dominant shrubs, there are differences in the vegetation structure.

  • Chaparral tends to be a taller, denser vegetation with very little herbaceous understory (except for period right after fire).
  • CSS, in contrast, is shorter and tends to have a lot more herbaceous vegetation in it, even in periods between fires.

Chaparral vs CSS

Despite the differences between chaparral and CSS, both harbor a large number of species that are endemic to the California Floristic Province.