LOCATION WINDOWPEAK              CA

Established Series
CES/JBB/JTW
09/2021

WINDOWPEAK SERIES

The Windowpeak series consists of very deep, well or somewhat excessively drained soils formed in colluvium and/or till derived from granite and granodiorite. Windowpeak soils are on moraines, mountain slopes, and glacial-valley walls and floors in the Sierra Nevada Mountains. Slopes range from 3 to 60 percent. The mean annual precipitation is about 1095 mm and the mean annual air temperature is about 6 degrees C.

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

TYPICAL PEDON: Windowpeak very stony loamy fine sand on a northeast-facing (30 degree), 44 percent slope under a canopy of red fir at an elevation of 2429 meters. (Colors are for dry soils unless otherwise noted. When described on August 24, 2017 the soil was moist throughout.)

Oi--0 to 7 cm; slightly decomposed plant material, 7.5YR 3/3) moist; very strongly acid (pH 5.0); clear wavy boundary. (0 to 7 cm thick)

A--7 to 27 cm; brown (7.5YR 4/2) very stony loamy fine sand, very dark brown (7.5YR 2.5/2) moist; 4 percent clay; weak medium granular structure; soft, very friable, nonsticky, nonplastic; common very fine, fine, medium, coarse, and very coarse roots throughout; many very fine irregular pores; 10 percent subangular indurated granodiorite gravel, 10 percent subangular indurated granodiorite cobbles, 20 percent subangular indurated granodiorite stones; NaF pH 10.5; strongly acid (pH 5.2); clear wavy boundary. (5 to 25 cm thick)

Bw1--27 to 85 cm; brown (7.5YR 4/2) very cobbly loamy fine sand, dark brown (7.5YR 3/2) moist; 5 percent clay; weak medium subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine, fine, medium, coarse, and very coarse roots throughout, and common very coarse roots at top of horizon; common very fine irregular pores; 20 percent subangular indurated granodiorite gravel, 25 percent subangular indurated granodiorite cobbles, 10 percent subangular indurated granodiorite stones; NaF pH 10.0; strongly acid (pH 5.2); clear wavy boundary. (15 to 60 cm thick)

Bw2--85 to 130 cm; brown (7.5YR 5/3) very cobbly loamy sand, brown (7.5YR 4/3) moist; 4 percent clay; weak medium subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine ,fine, and medium roots throughout; common fine irregular pores; 15 percent subangular indurated granodiorite gravel, 25 percent subangular indurated granodiorite cobbles, 3 percent subangular indurated granodiorite stones; NaF pH 9.5; very strongly acid (pH 5.0); clear wavy boundary. (0 to 60 cm thick)

C--130 to 155 cm; brown (10YR 5/3) very cobbly sand, brown (10YR 4/3) moist; 3 percent clay; structureless massive; soft, very friable, nonsticky, nonplastic; common fine roots throughout; common fine irregular pores; 15 percent subangular indurated granodiorite gravel, 20 percent subangular indurated granodiorite cobbles; NaF pH 9.5; very strongly acid (pH 5.0).

TYPE LOCATION: Tulare County, California, Big Baldy Trail, about 2.5 km south of trailhead; USGS 7.5 minute topographic quadrangle: General Grant Grove, CA; WGS84 36.674217 latitude and -118.881185 longitude; UTM zone 11 4060382 meters N 331899 meters E NAD83.

RANGE IN CHARACTERISTICS:
Soil temperature: The mean annual soil temperature at 50 cm is 0 to 8 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: 50 to 100 cm

Reaction: slightly to strongly acid

Base saturation: less than 50 percent in some or all parts of the epipedon (by ammonium acetate)

Acid-oxalate extractable Al plus 1/2 Fe: 0.4 to 1.0 percent (by weight) to a depth of 150 cm

Volcanic glass: 5 to 30 percent in the 0.02 to 2.0 mm fraction in an 18 cm thick layer within a depth of 75cm from the mineral soil surface

Particle size control section weighted average:
Rock fragments: 35 to 70 percent, with 20 to 60 percent gravel, 15 to 35 percent cobbles, 5 to 35 percent stones, and 0 to 15 percent boulders.
Clay content: 1 to 10 percent
NaF pH: 9.0 to 11.0

A horizon
Hue: 7.5YR, 10YR
Value: 3 to 5 dry, 2 or 3 moist
Chroma: 2 or 3, dry or moist
Texture: sand, loamy coarse sand, loamy sand, loamy fine sand
Clay content: 2 to 8 percent
Rock fragments: 5 to 65 percent
5 to 50 percent gravel
0 to 30 percent cobbles
0 to 30 percent stones
0 to 30 percent boulders

Bw1 horizon
Hue: 7.5YR, 10YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 to 4 dry, 2 or 3 moist
Texture: sand, loamy coarse sand, loamy sand, loamy fine sand
Clay content: 1 to 10 percent
Rock fragments: 15 to 70 percent
10 to 45 percent gravel
5 to 30 percent cobbles
0 to 30 percent stones
0 to 30 percent boulders

Bw2 horizon
Hue: 7.5YR, 10YR
Value: 4 or 5 dry, 3 or 4 moist
Chroma: 3 or 4 dry, 2 to 4 moist
Texture: sand, loamy coarse sand, loamy sand, loamy fine sand
Clay content: 1 to 10 percent
Rock fragments: 30 to 70 percent
15 to 45 percent gravel
15 to 30 percent cobbles
0 to 30 percent stones
0 to 30 percent boulders

C horizon
Hue: 7.5YR, 10YR, 2.5Y
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 2 to 4, dry or moist
Texture: sand, loamy coarse sand, loamy sand, loamy fine sand
Clay content: 1 to 8 percent
Rock fragments: 35 to 75 percent
15 to 50 percent gravel
10 to 30 percent cobbles
10 to 30 percent stones
0 to 15 percent boulders

COMPETING SERIES: These are the Doncecil (T), Kanawyer (T), Pajo, and Tripod soils. Doncecil soils formed in colluvium on mountain slopes and have umbric epipedons less than 50 cm thick. Kanawyer soils formed in till and colluvium on moraines and mountain slopes, have umbric epipedons less than 50 cm thick, and have a densic contact between 100 and 150 cm from the mineral soil surface. Pajo soils are 50 to 100 cm to a lithic contact. Tripod soils have ashy textures in the A horizon, and have hues 10YR or yellower throughout the profile.

GEOGRAPHIC SETTING: The Windowpeak soils are on linear backslopes and footslopes on mountain slopes, glacial-valley walls, colluvial aprons on glacial-valley floors and cirques, and moraines on plateaus. Slopes range from 3 to 60 percent. These soils formed in colluvium and till derived from granite and granodiorite, and less commonly, metamorphic rocks. Elevation is 1825 to 3235 meters. The climate is Mediterranean with warm, dry summers and cool, moist winters. The mean annual precipitation is 445 to 1515 mm and the mean annual air temperature is 2 to 10 degrees C. The frost free season is 60 to 160 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Beetlerock and Hockett soils. Beetlerock soils average less than 35 percent rock fragments in the particle size control section and are on linear to convex backslopes of mountain slopes. Hockett soils are 50 to 100 cm deep to a lithic contact and are on linear to concave backslopes of structural benches and mountain slopes.

DRAINAGE AND PERMEABILITY: Well or somewhat excessively drained, high to very high saturated hydraulic conductivity.

USE AND VEGETATION: This soil is used for recreation, wildlife habitat, and watershed. Vegetation is red fir, white fir, Sierra lodgepole pine, and Jeffrey pine, with an understory of chinquapin and whitethorn ceanothus.

DISTRIBUTION AND EXTENT: Sierra Nevada Mountains of California; MLRA 22A. These soils are of moderate 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 a local physiographic feature in Sequoia National Park.

REMARKS:
Particle Size Control Section for this pedon: 32 to 107 cm
Diagnostic horizons and features recognized in this pedon are:
Umbric Epipedon 7 to 85 cm

ADDITIONAL DATA:
NASIS User Pedon ID: 2017CA7925010

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

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National Cooperative Soil Survey
U.S.A.