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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
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 is highly asymmetrical with a long, 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 certain 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 of Paleozoic and Mesozoic ages. 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 "D" Southern Sierra Upper Montane
This LRU occurs between 6,560 feet to 9,200 feet, but may range higher on southern aspects. MAAT ranges from 38 to 47 degrees F, MAP ranges from 25 to 50 inches, and the frost free season ranges from 60 to 125 days. Forest are dominated by California red fir (Abies magnifica); mixed California red fir-western white pine-Sierra lodgepole pine; and Jeffrey pine-Sierra lodgepole pine-California red fir mix. Shrublands are dominated by greenleaf manzanita (Arctostaphylos patula) or bush chinquapin.Ecological site concept
Site is on colluvial, north to east facing, mountain slopes (40 to 60%). Soils are deep to very deep with sandy skeletal particle size class. Open forest of California red fir (Abies magnifica), western white pine (Pinus monticola), lodgepole pine (Pinus contorta), often with pinemat manzanita (Arctostaphylos nevadensis) in understory.
Table 1. Dominant plant species
Tree (1) Abies magnifica
(2) Pinus monticolaShrub (1) Arctostaphylos nevadensis
(2) Chrysolepis sempervirensHerbaceous Not specified