Subsection M261Af
Lower Salmon Mountains

Lithology and Stratigraphy.  This subsection contains a variety of Paleozoic to Jurassic metavolcanic and metasedimentary rocks, including components of ophiolitic sequences, of mostly Western Hayfork and Rattlesnake Creek terranes, and some Sawyers Bar terrane up Wooley Creek.  The rocks were intruded by Mesozoic granitic rocks, generally quartz diorite to slightly more silicic rocks.

Geomorphology.   This is a subsection of mountains with rounded ridges, steep sides, and narrow canyons.  Both large and small landslides are common.  Slopes on highly serpentinized peridotite are generally moderately steep, rather than steep, reflecting its susceptibility to mass wasting.  There are narrow floodplains and high terraces along the Klamath River and its tributaries.  The elevation range is about 600 to nearly 5000 feet.  Mass wasting and fluvial erosion are the main geomorphic processes.

Soils.  The soils are mostly Dystric and Dystric Lithic Xerochrepts, Ultic Haploxeralfs, and Typic Haploxerults.  Soils on granitic rocks are mostly Dystric and shallow Dystric Xerochrepts.  Typic Argixerolls and Typic and Mollic Haploxeralfs occur on serpentinite and serpentinized peridotite.  Xeric Haplohumults occur on high terraces and other stable land surfaces.  The soils are well drained.  Soil temperature regimes are mesic.  Soil moisture regimes are xeric.

Vegetation.  The predominant natural plant communities are Douglas-fir - tanoak series, Douglas-fir series, and Mixed conifer series, and, on ultramafic rocks, Jeffrey pine series.   Canyon live oak series is common on very steep rocky slopes with stony soils.  White fir series occurs at higher elevations.

Characteristic series by lifeform include:
Grasslands: California annual grassland series.
Shrublands: Brewer oak series, Greenleaf manzanita series, Huckleberry oak series, Sadler oak series, Tobacco brush series, Wedgeleaf ceanothus series, Whiteleaf manzanita series.
Forests and woodlands: Black oak series, Canyon live oak series, Douglas-fir series, Douglas-fir - ponderosa pine series, Douglas-fir - tanoak series, Jeffrey pine series, Knobcone pine series, Oregon white oak series, Tanoak series, White alder series, White fir series.

Surface Water.  Runoff is rapid.  It drains to the Klamath River, which flows through the subsection.   The larger streams are perennial.  There are no lakes in the subsection.