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General information
Draft. A draft ecological site description is either incomplete or has not undergone quality control and quality assurance review.
MLRA notes
Major Land Resource Area (MLRA): 022A–Sierra Nevada and Tehachapi Mountains
MLRA 22A
Major Land Resource Area 22A, Sierra Nevada Mountains, is located predominantly in California and a small section of western Nevada. The area lies completely within the Sierra Nevada Section of the Cascade-Sierra Mountains Province. The Sierra Nevada range has s gentle western slope, and a very abrupt eastern slope. The Sierra Nevada consists of hilly to steep mountains and occasional flatter mountain valleys. Elevation ranges between 1,500 and 9,000 ft throughout most of the range, but peaks often exceed 12,000 ft. The highest point in the continental US occurs in this MLRA (Mount Whitney, 14,494 ft). Most of the Sierra Nevada is dominated by granitic rock of the Mesozoic age, known as the Sierra Nevada Batholith. The northern half is flanked on the west by a metamorphic belt, which consists of highly metamorphosed sedimentary and volcanic rocks. Additionally, glacial activity of the Pleistocene has played a major role in shaping Sierra Nevada features, including cirques, arĂȘtes, and glacial deposits and moraines. Average annual precipitation ranges from 20 to 80 inches in most of the area, with increases along elevational and south-north gradients. Soil temperature regime ranges from mesic, frigid, and cryic. Due to the extreme elevational range found within this MLRA, Land Resource Units (LRUs) were designated to group the MLRA into similar land units.
LRU "K" Southern Sierra Lower Montane
Elevations are typically between 3, 000 and 5,000 ft, but varies due to aspect and latitude. The frost free season is 125 to 225 days, MAAT is 50 to 60 degrees F, and MAP ranges from 23 to 44 inches. Geology is typical granite. Canyon live oak (Quercus chrysolepis) and interior live oak (Quercus wislizeni) woodlands dominate. Forest composed of black oak (Quercus kellogii), ponderosa pine (Pinus ponderosa) and incense cedar (Calocedrus decurrens) are present on northern aspects. Chaparral species include chamise (Adenostoma fasciculatum, buckbrush, and mohagany.Ecological site concept
This site occurs on deep to very deep loamy-skeletal soils on shoulders and back slopes (often exceeding 60% slope). Similar concept to the H001 Mesic Mountain Slopes, but lower in elevation (< 4,921 ft (1,500 m) and more of an oak montane site. Vegetation consists of dense California black oak (Quercus kellogii) and canyon live oak (Quercus chrysolepis), with scattered overstory incense cedar (Calocedrus decurrens), poison oak (Toxicodendron diversilobum) and gooseberry (Ribes spp.), and to a limited extent western bracken fern (Pteridium alquilinum) form the understory.
Table 1. Dominant plant species
Tree (1) Quercus kelloggii
(2) Calocedrus decurrensShrub (1) Ceanothus integerrimus
(2) Umbellularia californicaHerbaceous Not specified