LOCATION GRUNIGEN                CA

Tentative Series
JBB/CES/JTW
09/2021

GRUNIGEN SERIES

The Grunigen series consists of shallow, well drained soils formed in colluvium over residuum weathered from granite. The Grunigen soils are on steep mountain slopes and canyon walls of the Sierra Nevada Mountains. Slopes range from 30 to 90 percent. The mean annual precipitation is about 885 mm and the mean annual air temperature is about 13 degrees C.

TAXONOMIC CLASS: Loamy, isotic, mesic Lithic Ultic Haploxerolls

TYPICAL PEDON: Grunigen sandy loam on an east-facing (100 degree), 60 percent slope under a canopy of live oaks at an elevation of 1090 meters. (Colors are for dry soils unless otherwise noted. When described on February 22, 2013 the soil was moist throughout.)

Oi--0 to 2 cm; very dark grayish brown (10YR 3/2) slightly decomposed plant material, very dark brown (10YR 2/2) moist; neutral (pH 7.2); abrupt wavy boundary. (2 to 7 cm thick)

A1--2 to 8 cm; dark grayish brown (10YR 4/2) sandy loam, black (10YR 2/1) moist; 6 percent clay; weak medium granular structure; soft, very friable, nonsticky, nonplastic; few very fine and fine roots throughout; many fine dendritic tubular pores; 4 percent fine mica flakes, muscovite; 2 percent subangular indurated granite gravel; NaF pH 9.0; neutral (pH 7.2); abrupt wavy boundary.

A2--8 to 20 cm; brown (10YR 4/3) sandy loam, very dark brown (10YR 2/2) moist; 6 percent clay; weak medium granular structure; soft, very friable, nonsticky, nonplastic; few very fine and fine roots throughout; few very fine dendritic tubular pores; 4 percent fine mica flakes, muscovite; NaF pH 9.5; neutral (pH 7.2); clear wavy boundary. (combined thickness of the A horizons is 10 to 30 cm)

Bw--20 to 31 cm; brown (10YR 4/3) sandy loam, very dark grayish brown (10YR 3/2) moist; 8 percent clay; weak medium granular, and weak medium subangular blocky structure; soft, very friable, nonsticky, nonplastic; few very fine and fine, and common coarse and very coarse roots throughout; few very fine dendritic tubular pores; 4 percent fine mica flakes, muscovite; NaF pH 9.5; neutral (pH 6.6); very abrupt wavy boundary. (10 to 30 cm thick)

R--31 to 40 cm; very strongly cemented granite bedrock, fractured at intervals of 45 to less than 100 cm.

TYPE LOCATION: Tulare County, California, about 1 km from the Middle Fork Kaweah trailhead; USGS 7.5 minute topographic quadrangle: Lodgepole, California; WGS84 36.531282 latitude and -118.747523 longitude; UTM zone 11 4044298 meters N 343556 meters E NAD83.

RANGE IN CHARACTERISTICS:
Soil temperature: The mean annual soil temperature at 50 cm is 11 to 15 degrees C and the difference between mean summer and mean winter soil temperature is greater than 6 degrees C. The soils have a mesic temperature regime.

Soil moisture: The soils have a xeric soil moisture regime. The soil moisture control section is dry in all parts from about June to October (about 150 days).

Diagnostic Feature(s):
Mollic epipedon thickness: 18 to 40 cm
Depth to lithic contact: 25 to 50 cm

Bedrock hardness ranges from moderately cemented to indurated.

Organic matter: 1 to 5 percent

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

Particle size control section weighted average:
Rock fragments: 0 to 20 percent, with 0 to 15 percent gravel and 0 to 15 percent cobbles.
Pararock fragments: 0 to 15 percent paragravel
Clay content: 6 to 12 percent
NaF pH: 8.5 to 10.0

A horizons
Hue: 7.5YR, 10YR
Value: 4 dry, 2 or 3 moist
Chroma: 2 or 3, dry or moist
Texture: sandy loam, loamy sand
Clay content: 5 to 12 percent
Rock fragments: 0 to 15 percent gravel
Pararock fragments: 0 to 15 percent paragravel
Reaction: moderately acid to neutral

Bw horizon
Hue: 7.5YR, 10YR
Value: 4 dry, 2 or 3 moist
Chroma: 2 or 3, dry or moist
Texture: sandy loam
Clay content: 6 to 12 percent
Rock fragments: 0 to 20 percent gravel
Reaction: moderately acid to neutral

COMPETING SERIES: These are the Glade (MLRA 3) and Haro (MLRA 2) soils. The Glade soils are formed in extrusive igneous rocks and volcanic ash, average up to 18 percent clay in the control section, and are dry for 75 to 90 days. The Haro soils are formed in metasedimentary rock, average up to 18 percent clay in the control section, and are dry for 75 to 90 days.

GEOGRAPHIC SETTING: The Grunigen soils are on concave backslopes in drainages on mountain slopes and canyon walls. Slopes range from 30 to 90 percent. These soils formed in residuum weathered from granite. Elevation is 745 to 2215 meters. The climate is Mediterranean with warm, dry summers and cool, moist winters. The mean annual precipitation is 710 to 1045 mm and the mean annual air temperature is 9 to 16 degrees C. The frost free season is 150 to 255 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Edencreek and Mororock soils. Edencreek soils are on convex mountain slopes, have a clay increase in the profile that meets the requirements of an argillic horizon, and are between 50 and 100 cm to a paralithic contact. Mororock soils are on steep linear mountain slopes, formed in colluvium, and are greater than 150 cm to a bedrock contact.

DRAINAGE AND PERMEABILITY: Well drained, high saturated hydraulic conductivity.

USE AND VEGETATION: This soil is used for recreation, wildlife habitat, and watershed. Vegetation is canyon live oak, interior live oak, and California bay laurel.

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

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

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

REMARKS:
Particle Size Control Section for this pedon: 2 to 31 cm.
Diagnostic horizons and features recognized in this pedon are:
Mollic Epipedon 0 to 31 cm
Lithic Contact 31 cm

ADDITIONAL DATA:
NASIS User Pedon ID: 2013CA7928005

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

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National Cooperative Soil Survey
U.S.A.