LOCATION DORST CA

Established Series
CES/JTW
09/2021

DORST SERIES

The Dorst series consists of shallow, somewhat excessively drained soils formed in colluvium, slope alluvium, and residuum derived from granitic rocks. Dorst soils are on structural benches and mountain slopes in the Sierra Nevada Mountains. Slopes range from 2 to 90 percent. The mean annual precipitation is about 980 mm and the mean annual air temperature is about 6 degrees C.

TAXONOMIC CLASS: Sandy-skeletal, isotic, frigid Lithic Humixerepts

TYPICAL PEDON: Dorst very gravelly coarse sand on an east-facing (103 degree), 33 percent slope under western juniper, Jeffrey pine, and greenleaf manzanita at an elevation of 2333 meters. (Colors are for dry soils unless otherwise noted. When described on September 12, 2014 the soil was dry throughout.

Oi--0 to 2 cm; slightly decomposed plant material, very dark grayish brown (10YR 3/2) moist; about 100 percent fiber, 90 percent rubbed; moderately acid (pH 5.8); abrupt smooth boundary. (0 to 9 cm thick)

A--2 to 14 cm; grayish brown (10YR 5/2) very gravelly coarse sand, very dark grayish brown (10YR 3/2) moist; 2 percent clay; structureless single grain; loose, loose, nonsticky, nonplastic; common very fine and few fine roots throughout; common very fine and fine interstitial pores; 38 percent subangular strongly cemented granite gravel; NaF pH 9.0; moderately acid (pH 5.6); abrupt smooth boundary. (6 to 25 cm thick)

Bw--14 to 26 cm; grayish brown (10YR 5/2) very gravelly loamy coarse sand, very dark brown (10YR 2/2) moist; 4 percent clay; moderate medium subangular blocky structure; slightly hard, friable, nonsticky, nonplastic; common very fine, fine, and medium roots throughout; common very fine and fine, and common medium irregular pores; 40 percent angular strongly cemented granite gravel; NaF pH 9.0; strongly acid (pH 5.4); very abrupt smooth boundary. (12 to 21 cm thick)

R--26 cm; Indurated granodiorite bedrock; common very fine, fine, medium, and coarse roots in mat at top of horizon.

TYPE LOCATION: Tulare County, California, in Comanche Meadow area of Sequoia National Park (about 2.5 km southwest of Sugarloaf Peak); USGS 7.5 minute topographic quadrangle: Mt. Silliman, CA; WGS84 36.713543 latitude and -118.677390 longitude; UTM zone 11 4064406 meters N 350189 meters E NAD83.

RANGE IN CHARACTERISTICS:
Soil temperature: The mean annual soil temperature at 50 cm is 3 to 9 degrees C and the difference between mean summer and mean winter soil temperature is greater than 6 degrees C. The soils have a frigid temperature regime.

Soil Moisture: The soils have a xeric soil moisture regime. The soil moisture control section is dry in all parts from about August to October (about 90 days).

Diagnostic Feature(s):
Umbric epipedon thickness: 25 to 40 cm
Depth to lithic contact: 25 to 50 cm
Reaction: very strongly to slightly acid

Base saturation: less than 50 percent (by ammonium acetate)

Particle size control section weighted average:
Rock fragments: 35 to 70 percent, with 15 to 65 percent gravel, 0 to 45 percent channers, 0 to 20 percent cobbles, 0 to 50 percent stones, and 0 to 40 percent flagstones.
Clay content: 1 to 8 percent
NaF pH: 8.5 to 11

A horizon
Hue: 7.5YR or 10YR
Value: 3 to 5 dry, 2 or 3 moist
Chroma: 2 or 3 dry, 2 moist
Texture: coarse sand, sand, loamy coarse sand, loamy sand, loamy fine sand
Clay content: 1 to 10 percent
Rock fragments: 10 to 70 percent
0 to 45 percent gravel
0 to 40 percent channers
0 to 30 percent cobbles
0 to 30 percent flagstones
0 to 30 percent stones

Bw horizon
Hue: 7.5YR or 10YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 or 3 dry, 2 moist
Texture: coarse sand, sand, loamy coarse sand, loamy sand
Clay content: 1 to 6 percent
Rock fragments: 10 to 70 percent
0 to 45 percent gravel
0 to 40 percent channers
0 to 30 percent cobbles
0 to 35 percent flagstones
0 to 35 percent stones

C horizon (when present)
Hue: 10YR
Value: 4 to 6 dry, 2 to 4 moist
Chroma: 2 or 3, dry or moist
Texture: sand, loamy sand
Clay content: 1 to 4 percent
Rock fragments: 25 to 70 percent
25 to 65 percent gravel
0 to 45 percent channers
0 to 15 percent cobbles
0 to 15 percent flagstones
0 to 15 percent stones

COMPETING SERIES: There are no other series in this family at this time.

GEOGRAPHIC SETTING: The Dorst soils are on linear to convex summits and shoulders of structural benches of glacial-valley walls, cirques, plateaus, and mountain slopes. Slopes range from 2 to 90 percent. These soils formed in in colluvium, slope alluvium, and residuum derived from granitic rocks. Elevation is 1750 to 3225 meters. The climate is Mediterranean with warm, dry summers and cool, moist winters. The mean annual precipitation is 450 to 1515 mm and the mean annual air temperature is 2 to 9 degrees C. The frost free season is 80 to 165 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hockett and Windowpeak soils. Hockett soils are on linear to concave positions on structural benches and are 50 to 100 cm to a lithic contact. Windowpeak soils are on linear to convex backslopes of mountain slopes, and are greater than 200 cm to a lithic contact.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained; high to very high saturated hydraulic conductivity. Saturated hydraulic conductivity of the bedrock is very low to high.

USE AND VEGETATION: This soil is used for recreation, wildlife habitat, and watershed. Vegetation is western juniper, Jeffrey pine, white fir, greenleaf manzanita, chinquapin, and perennial grasses and forbs.

DISTRIBUTION AND EXTENT: Sierra Nevada Mountains of California; MLRA 22A. These soils are moderately extensive.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Davis, California

SERIES PROPOSED: Tulare County, California in Sequoia and Kings Canyon National Parks. Source of name from a campground In Sequoia National Park.

REMARKS:
Particle Size Control Section for this pedon: 2 to 26 cm
Diagnostic horizons and features recognized in this pedon are:
Umbric Epipedon 2 to 26 cm
Lithic Contact 26 cm

ADDITIONAL DATA:
NASIS User Pedon ID: 2014CA7921060

Soil classified using the 12th Edition of the Keys to Soil Taxonomy.

National Cooperative Soil Survey
U.S.A.