Hardwood Rangeland Habitats: Although there are numerous ways to classify California’s oak-dominated woodlands, the five vegetation types used in the California Wildlife Habitat Relationships System (CWHR) are the most commonly used and are described below. The CWHR types are based on the dominant tree species, and we include information on Valley Oak Woodland, Blue Oak Woodland, Blue Oak-Foothill Pine Woodland, Coastal Oak Woodland, and Montane Hardwood Forest here for your reference.
Blue Oak-Foothill Pine Woodland Vegetation Composition and Structure
Blue oak-foothill pine woodlands have a diverse mix of hardwoods, conifers, and shrubs, and widely variable overstories. Foothill pine (formerly known as digger pine) and blue oak typically form most of the overstory of this highly variable habitat type. Blue oak usually most abundant, although foothill pine is taller and dominates the overstory. Stands dominated by foothill pine have low blue oak density because of its shade intolerance. In the Sierra Nevada foothills, interior live oak and California buckeye are often associated with this type. Interior live oak becomes more abundant on steeper slopes, shallower soils, and at higher elevations. Coast live oak, valley oak, and California buckeye occur with this community in the Coast Range. In the southern Coast Range and Tehachapi Mountains, California juniper also occurs. Shrub associates include several ceanothus and manzanita species, poison-oak and California redbud, and are usually clumped in areas of full sunlight.
Blue oak and foothill pine are relatively long-lived, but foothill pine tends to grow faster than blue oak. Historically, fires occurred every 5 to 25 years in this vegetation community. Regeneration is generally thought to be infrequent throughout California. Following fire, young, vigorous blue oaks sprout well, but older, more decadent trees do not. Therefore, younger stands are more likely to replace themselves after fires. Foothill pine is susceptible to severe damage to fire. This is due to the thin bark of young trees and high resin content in the sap. Furthermore, foothill pine does not reproduce by sprouting, so fire management as a tool should be carefully considered.
Blue oak-foothill pine woodlands are found on steeper, dryer slopes with shallower soils than blue oak woodlands. At lower elevations on gentle slopes, these two communities intermix with grasslands. At higher elevations on steeper slopes, the communities are mixed with grasslands and shrublands. Riparian woodlands may bisect these mosaics along permanent and intermittent watercourses. Blue oak-foothill pine woodlands are found throughout the range of blue oak and form a nearly continuous band along the Sierra Nevada-Cascade foothills of the Sacramento-San Joaquin Valley, except for a gap in Tulare and southern Fresno counties. Elevation ranges from 500 feet in the north to 3000 feet in the south.
This woodland type occurs on a variety of well-drained soils. Terrain is hilly and generally dry, and water is unavailable for much of the year.
Vertebrate Wildlife Species Associations of Blue Oak-Foothill Pine Woodlands
These PDFs provide a list of the species of amphibians, birds, mammals, and reptiles that are predicted to use blue oak-foothill pine woodlands habitats. The lists are derived from Version 5.0 of the California Wildlife Habitat Relationships System (CWHR) and includes those species that are predicted to use one or more hardwood rangeland canopy cover classes for breeding, feeding, and/or cover. Most waterbirds like ducks, geese, gulls, and shorebirds were not included in the CWHR predictions because they are mostly associated with lakes, ponds, and rivers. The CWHR System is managed by the California Department of Fish and Wildlife.
The tables also indicate which of these hardwood rangeland species are predicted to use several important habitat elements of the California hardwood rangeland habitats. The elements listed include: acorns; riparian habitat; logs, slash, and brush piles; snags; burrows, rocks, talus, caves and cliffs; and vernal pools and wetland.
Also included are those species which have special status designation by the California Department of Fish and Wildlife and/or the U.S. Fish and Wildlife Service. Most of these species, particularly mammals and reptiles, have locally restricted subspecies that have a special status designation. If you have a species with a special status, you need to get more detailed local information on whether your population is in a subspecies with this special designation. You need to ensure that there is adequate protection for these species, and to make sure that you are not in violation of state or federal endangered species regulations.
Landowners and managers using these lists can get a general idea of which species might be located on a particular property, and which important habitat elements are important to their use of an area. These lists should not substitute for local-based surveys. Landowners may wish to consult with local CDFW biologists, or consulting wildlife biologists for more detailed local surveys of their lands.