Subsection M261Ae
Scott Bar Mountain

Lithology and Stratigraphy.  This subsection contains a variety of Paleozoic to Jurassic metavolcanic and metasedimentary rocks, including components of ophiolitic sequences, of the Rattlesnake Creek, Western Hayfork, and Sawyers Bar terranes.  Metamorphic rocks of the Stuart Fork Formation occur between the Soap Creek Ridge fault and the Eastern Klamath Belt.  The rocks of this subsection were intruded by Mesozoic granitic rocks, generally quartz diorite to slightly more silicic rocks.  The Condrey Mountain Schist, some of which is in this subsection, is a greenschist - blueschist facies volcanic sequence and subduction complex.  Cretaceous marine sedimentary rocks of the Hornbrook Formation cover the eastern edge of the subsection.

Geomorphology.  This is a subsection of mountains with rounded ridges, steep sides, and narrow canyons.  Although the mountains are generally aligned toward the north, the Scott Bar Mountains are aligned toward the east-northeast, nearly parallel to the Soap Creek Ridge fault that separates this subsection from the Eastern Klamath Belt.  Slopes on Condrey Mountain Schist are generally moderately steep, rather than steep, reflecting its susceptibility to mass wasting.  The elevation range is about 1500 to 6300 feet.  Mass wasting and fluvial erosion are the main geomorphic processes.

Soils.  The soils are mostly Dystric and Dystric Lithic Xerochrepts and Ultic Haploxeralfs.  Typic and Pachic Xerumbrepts occur at higher elevations.  Soils on granitic rocks are mostly Dystric and shallow Dystric Xerochrepts.  Soils on Cretaceous marine sedimentary rocks are mostly Mollic Haploxeralfs, Vertic Argixerolls, and Leptic Haploxererts.  The soils are well drained.  Soil temperature regimes are predominantly mesic, with some frigid at higher elevations.  Soil moisture regimes are xeric.

Vegetation.   The predominant natural plant communities are Mixed conifer series and Douglas-fir - ponderosa pine series, and, on ultramafic rocks, Jeffrey pine series and Foxtail pine series.  Canyon live oak series is common on very steep rocky slopes with stony soils.  White fir series, and some Red fir series and Mixed subalpine forest series, occur at higher elevations.  Oregon white oak series occurs on the east side of the subsection, particularly on Cretaceous marine sedimentary rocks.

Characteristic series by lifeform include:
Grasslands: California annual grassland series, Montane meadow habitat, Nebraska sedge series, Rocky Mountain sedge series.
Shrublands: Big sagebrush series, Brewer oak series, Curlleaf mountain-mahogany series, Bush chinquapin series, Greenleaf manzanita series, Holodiscus series, Huckleberry oak series, Montane wetland shrub habitat, Mountain alder series, Rubber rabbitbrush series, Sitka alder series, Subalpine upland shrub habitat, Subalpine wetland shrub habitat, Tobacco brush series, Wedgeleaf ceanothus series, Whiteleaf manzanita series.
Forests and woodlands: Baker cypress stands, Black oak series, Canyon live oak series, Douglas-fir - Ponderosa pine series, Foxtail pine series, Jeffrey pine series, Mountain hemlock series, Oregon white oak series, Ponderosa pine series, Red fir series, Western juniper series, White fir series.

Surface Water.  Runoff is rapid.  It drains to the Scott and Klamath Rivers, which flow through the subsection.   All but the larger streams are dry through much or most of summer.  There are no lakes in the subsection.