Las Trampas Ridge
Map SatellitePortions of Las Trampas and Rocky Ridges are included in this park which is characterized by high ridges and steep slopes.
Vegetation includes several communities, with a mixed broadleaf forest dominant. Species found here include coast live oak, Quercus agrifolia, blue oak, Quercus douglasii, California buckeye, Aesculus californica, madrone, Arbutus menziesii, and California bay, Umbellularia californica. Much of the remaining area is grassland, with a number of exotics, and there is some chaparral with chamise, Adenostoma fasciculatum, Ceanothus spp., and Arctostaphylos spp.
Animal life is typical of the mid-Coast Ranges. Golden eagles, Aquila chrysaetos, are frequently sighted in the area. The rare Alameda striped racer, Masticophis lateralis euryxanthus, may occur here.
Geologically, the area is highly faulted. In the lower elevations the Pliocene Mulholland Formation is present. The ridges show exposures of the fossil-bearing upper Miocene marine sedimentary Neroly, Cierbo and Briones formations. Differential erosion has formed hogbacks and steep ridges.
Integrity: There are trails, roads and some park facilities, and the area is well used; however, much of the vegetation is only moderately disturbed.
Use: Educational, observational, present.
Ref: Ham, C. K., 1952. Geology of Las Trampas Ridge. Spec. Rep. 22, Calif. Div. of Mines.
November 1979
Inventory of California Natural Areas
Revision © 2009 Steven Louis Hartman
