LOCATION WOODWEST CAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, amorphic, frigid Lithic Haploxerands
TYPICAL PEDON: Woodwest very stony sandy loam, forested, on a 3 percent N facing slope under Jeffrey pine and squawcarpet at 5,000 feet elevation. (When described October 18, 1983, the soil was dry throughout. Colors are for dry soil unless otherwise noted).
The surface is covered with 15 percent stones, 10 percent cobbles and 35 percent pebbles.
A1--0 to 9 inches; dark brown (7.5YR 3/3) very stony sandy loam, very dark brown (10YR 2/2) moist; weak very fine granular structure; soft, very friable, nonsticky and slightly plastic; common very fine, few fine and medium roots; many very fine interstitial pores; 10 percent cobbles and 30 percent pebbles; sodium fluoride pH is 10.9; slightly acid (pH 6.5); clear smooth boundary.
A2--9 to 14 inches; brown (7.5YR 4/4) extremely cobbly sandy loam, dark brown (7.5YR 3/3) moist; weak fine granular structure; soft, very friable, nonsticky and slightly plastic; few very fine, common fine and medium roots, many very fine interstitial pores, 30 percent cobbles and 30 percent pebbles; sodium fluoride pH is 10.4; slightly acid (pH 6.5); clear smooth boundary. (The combined thickness of the A horizons is 10 to 15 inches).
Bw--14 to 19 inches; strong brown (7.5YR 4/6) extremely gravelly sandy loam, brown (7.5YR 4/4) moist; moderate fine subangular blocky structure; soft, very friable, nonsticky and slightly plastic; few very fine, fine and medium roots; many very fine interstitial pores; 15 percent cobbles and 55 percent pebbles; sodium fluoride pH is 10.0; slightly acid (pH 6.5); abrupt wavy boundary. (2 to 9 inches thick)
R--19 to 24 inches; fractured vesicular basalt with roots and soil in fractures.
TYPE LOCATION: Plumas County, California; about 4 miles W of Westwood; about 0.5 miles N of the intersection of Swain Mountain Road and Highway 36 on Swain Mountain Road, 140 feet S of the point where the underground cable crosses the road, 60 feet W of Road; 1,000 feet E and 100 feet S of the N 1/4 corner of section 4, T.28 N., R.8 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature varies from 44 to 46 degrees F. The thickness of the solum and depth to bedrock ranges from 12 to 20 inches. The soil moisture control section (11 inches to the Lithic contact) is dry from August 1 to November 1 (90 days) and is moist in some or all parts the rest of the time. The soil temperature exceeds 41 degrees F from May 1 to December 1 and exceeds 47 degrees F from June 1 to November 1. Rock fragments on the surface range from 5 to 30 percent stones, 5 to 20 percent cobbles and 20 to 40 percent gravel. The umbric epipedon ranges fro 10 to 14 inches thick. Sodium fluoride pH ranges from 10.0 to 11.0. Bulk density ranges from 0.7 to 0.9 g/cc. 15 bar water content of the fine earth fraction ranges from 15 to 20 percent. Acid-oxalate-extractable aluminum plus one half acid-oxlate-extractable iron ranges from 3.5 to 2 throughout. Base saturation by sum of cations ranges from 20 to 30 percent. Base saturation by ammonium acetate ranges from 30 to 40 percent.
The A horizon is 10YR 3/3, 3/4, 4/3, 4/4; 7.5YR 3/4 or 4/4, 3/3. Moist color is 10YR 2/2, 3/2; 7.5YR 3/2 or 3/3. It is sandy loam modified by 35 to 50 percent rock fragments.
The Bw horizon is 7.5YR 4/4, 4/6 or 5YR 4/4. Moist color is 7.5YR 3/4, 4/4 or 5YR 3/4. It is sandy loam modified by 50 to 80 percent rock fragments and has 7 to 12 percent clay.
Andic property data (see remarks for explanation):
Depth P-ret B.D. pHNaf Glass Alo Feo 15barH2O
0-9 96* 0.75* 10.9 5* 2.1* 1* 21.8
9-14 93* 0.80* 10.5 4* 1.9* 1* 15.5
14-19 88* 0.86* 10.0 3* 1.6* 1* 15.4
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Woodwest soils are on ridges of rolling lava flows. Slopes are 0 to 9 percent. The soils formed in material weathered andesite or basalt capped with a mantle of volcanic ash. Elevation is 4,960 to 5,200 feet. The climate is subhumid with warm dry summers and cold moist winters. The mean annual precipitation is about 30 to 40 inches with 60 to 100 inches of snow. The mean annual temperature is about 44 degrees F mean July temperature is about 60 degrees F and mean January temperature is about 26 degrees F. The frost-free season is 60 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Almanor(T), Baileycreek(T) and Weste(T) soils. All these soils are deeper than 20 inches to bedrock. Baileycreek and Weste soils have argillic horizons.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; runoff is very slow or slow; moderately rapid permeability.
USE AND VEGETATION: Woodwest soils are used for timber production. The vegetation is Jeffrey pine, white fir, squawcarpet, whitethorn and greenleaf manzanita.
DISTRIBUTION AND EXTENT: Northeastern Plumas County and western Lassen County, California. These soils of this series are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Plumas County, California; Susanville Area Soil Survey Area, California 1988.
REMARKS: This series was classified as medial-skeletal, frigic Lithic Xerumbrepts. With the addition of the Andisol order, this classification is changed. Soil chemical and physical properties based on lab analysis of this and other similar pedons.
Diagnostic horizons and features recognized in this pedon are:
Umbric epipedon - Zone from the surface of the soil to a depth of 14 inches (A1, A2 horizons).
Andic soil properties-zone from the mineral soil surface to a depth of 19 inches (A1, A2, Bw horizons).
Cambic horizon - Zone from about 14 to 19 inches (Bw horizon).
Andic property data definitions:
P-ret: phosphate retention of the less than 2mm fraction.
B.D.: bulk density of the less than 2mm fraction measured at 33kPa water retention.
pH NaF: pH of soil mixed with saturated sodium floride solution.
Glass: percent volcanic glass.
Alo: acid-oxalate-extractable aluminum of the less than 2mm fraction.
Feo: acid-oxalate-extractable iron of the less than 2mm fraction.
15 bar H20: dried 1500 kPa water retention as a percent.
Data elements with a * are estimated.
NC: not calculated.
ND: not done.