LOCATION DONCECIL                CA

Established Series
CES/JBB
09/2021

DONCECIL SERIES

The Doncecil series consists of very deep, somewhat excessively drained soils formed in colluvium and reworked till derived from granitic rocks. Doncecil soils are on mountain slopes and colluvial aprons of glacial-valley walls in the Sierra Nevada mountains. Slopes range from 20 to 60 percent. The mean annual precipitation is about 985 mm and the mean annual air temperature is about 6 degrees C.

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

TYPICAL PEDON: Doncecil very stony sand on a north-facing (345 degree), 55 percent slope under a canopy of white fir, sugar pine, and Jeffrey pine at an elevation of 2029 meters. (Colors are for dry soils unless otherwise noted. When described on June 14, 2014 the soil was moist throughout.)

Oi--0 to 2 cm; slightly decomposed plant material, very dark grayish brown (10YR 3/2) moist; neutral (pH 6.8); very abrupt wavy boundary. (0 to 5 cm thick)

A1--2 to 8 cm; dark grayish brown (10YR 4/2) very stony sand, very dark brown (7.5YR 2.5/2) moist; 4 percent clay; weak fine granular structure; soft, very friable, nonsticky, nonplastic; common fine roots throughout; many very fine irregular pores; 3 percent subrounded indurated granite gravel, 10 percent subrounded indurated granite cobbles, 30 percent subrounded indurated granite stones, 5 percent subrounded indurated granite boulders; NaF pH 8.5; slightly acid (pH 6.4); very abrupt wavy boundary.

A2--8 to 27 cm; brown (10YR 5/3) very stony loamy fine sand, dark brown (7.5YR 3/2) moist; 8 percent clay; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; common very fine, fine, and medium roots throughout; many very fine irregular pores; 5 percent subrounded indurated granite gravel, 10 percent subrounded indurated granite cobbles, 30 percent subrounded indurated granite stones, 5 percent subrounded indurated granite boulders; NaF pH 9.5; slightly acid (pH 6.2); gradual wavy boundary. (combined thickness of A horizons is 5 to 30 cm)

Bw--27 to 83 cm; pale brown (10YR 6/3) very stony sand, brown (10YR 4/3) moist; 2 percent clay; weak medium subangular blocky structure; slightly hard, very friable, nonsticky, nonplastic; common very fine, fine, medium, and very coarse roots throughout; common very fine and fine irregular pores; 10 percent subrounded indurated granite gravel, 5 percent subrounded indurated granite cobbles, 25 percent subrounded indurated granite stones; NaF pH 9.0; slightly acid (pH 6.2); abrupt wavy boundary. (15 to 50 cm thick)

C1--83 to 130 cm; very pale brown (10YR 7/4) very gravelly sand, grayish brown (10YR 5/2) moist; 2 percent clay; structureless single grain; loose, loose, nonsticky, nonplastic; common fine, medium, and very coarse roots throughout; many very fine interstitial pores; 50 percent subrounded indurated granite gravel, 5 percent subrounded indurated granite cobbles; NaF pH 9.5; moderately acid (pH 6.0); abrupt wavy boundary.

C2--130 to 190 cm; pale yellow (2.5Y 7/3) very gravelly sand, gray (10YR 6/1) moist; 2 percent clay; structureless single grain; loose, loose, nonsticky, nonplastic; common fine and medium roots throughout; many very fine interstitial pores; 40 percent subangular indurated granite gravel; NaF pH 9.5; slightly acid (pH 6.4); abrupt wavy boundary. (combined thickness of C horizons is 30 to 120 cm)

C3--190 to 200 cm; light yellowish brown (10YR 6/4) gravelly sand, brown (7.5YR 5/4) moist; 3 percent clay; structureless single grain; loose, loose, nonsticky, nonplastic; common fine and coarse roots throughout; many very fine interstitial pores; 30 percent subrounded indurated granite gravel; NaF pH 9.0; moderately acid (pH 6.0).

TYPE LOCATION: Fresno County, California, Don Cecil Trail; USGS 7.5 minute topographic quadrangle: Cedar Grove, California; WGS84 36.777386 latitude and -118.695503 longitude; UTM zone 11 4071519 meters N 348696 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: 25 to 50 cm

Reaction: slightly acid to strongly acid

Base saturation: less than 50 percent. (By ammonium acetate)

Acid-oxalate extractable Al plus 1/2 Fe: 0.4 to 2.0 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 75 cm from the mineral soil surface

Particle size control section weighted average:
Rock fragments: 35 to 70 percent, with 25 to 50 percent gravel, 5 to 50 percent cobbles, 5 to 50 percent stones, and 0 to 20 percent boulders.
Clay content: 1 to 7 percent
NaF pH: 9.0 to 10.5

A horizon
Hue: 10YR, 2.5Y
Value: 3 to 5 dry, 2 or 3 moist
Chroma: 2 or 3 dry, 1 to 3 moist
Texture: sand, loamy coarse sand, loamy sand, loamy fine sand, sandy loam
Clay content: 1 to 10 percent
Rock fragments: 15 to 80 percent
0 to 60 percent gravel
10 to 35 percent cobbles
5 to 35 percent stones
0 to 5 percent boulders

Bw horizon
Hue: 10YR, 2.5Y
Value: 4 to 6 dry, 3 or 4 moist
Chroma: 3 or 4 dry, 2 to 4 moist
Texture: sand, loamy coarse sand, loamy sand, sandy loam
Clay content: 1 to 10 percent
Rock fragments: 15 to 80 percent
5 to 60 percent gravel
5 to 35 percent cobbles
5 to 35 percent stones
0 to 15 percent boulders

C horizon
Hue: 10YR, 2.5Y
Value: 5 to 7 dry, 4 to 7 moist
Chroma: 2 to 4 dry, 2 or 3 moist
Texture: coarse sand, sand, loamy coarse sand, loamy sand
Clay content: 0 to 8 percent
Rock fragments: 15 to 80 percent
15 to 60 percent gravel
0 to 35 percent cobbles
0 to 35 percent stones
0 to 15 percent boulders

COMPETING SERIES: There are the Kanawyer (T), Pajo, Tripod, and Windowpeak (T), soils. Kanawyer soils have a densic contact at 100 to 150 cm below 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. Windowpeak soils have umbric epipedons thicker than 50 cm.

GEOGRAPHIC SETTING: The Doncecil soils are on linear to concave backslopes of mountain slopes and colluvial aprons of glacial-valley walls. Slopes range from 20 to 60 percent. These soils formed in colluvium and reworked till derived from granite and granodiorite. Elevation is 1705 to 3245 meters. The climate is Mediterranean with warm, dry summers and cool, moist winters. The mean annual precipitation is 400 to 1265 mm and the mean annual air temperature is 3 to 9 degrees C. The frost free season is 70 to 145 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Beetlerock, Hockett, and Windowpeak soils. Beetlerock soils are on linear to convex mountain slopes and average less than 35 percent rock fragments in the particle size control section. Hockett soils are on structural benches and are 50 to 100 cm deep to bedrock. Windowpeak soils are on linear backslopes and footslopes of mountain slopes and have umbric epipedons thicker than 50 cm.

DRAINAGE AND PERMEABILITY: 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 western white pine, white fir, Jeffrey pine, Sierra lodgepole pine, greenleaf manzanita, whitethorn ceanothus, and chinquapin.

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: Fresno County, California in Sequoia and Kings Canyon National Parks. Source of name from a trail in Kings Canyon National Park.

REMARKS:
Particle Size Control Section for this pedon: 27 to 102 cm
Diagnostic horizons and features recognized in this pedon are:
Umbric Epipedon 2 to 27 cm

ADDITIONAL DATA:
NASIS User Pedon ID: 2014CA7925044

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

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National Cooperative Soil Survey
U.S.A.