LOCATION ALPINECO CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Oxyaquic Dystroxerepts
TYPICAL PEDON: Alpineco very stony coarse sandy loam--forest land. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered with 15 percent gravel, 5 percent stones, and 5 percent boulders.
A1--0 to 3 inches; grayish brown (10YR 5/2) very stony coarse sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine roots; common very fine interstitial and tubular pores; 20 percent gravel and 20 percent stones; slightly acid; clear wavy boundary. (2 to 5 inches thick)
A2--3 to 12 inches; brown (10YR 5/3) very stony coarse sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, common fine, and common medium roots; common fine interstitial and tubular pores; 25 percent gravel and 20 percent stones; slightly acid; clear wavy boundary. (5 to 15 inches thick)
Bw1--12 to 22 inches; light yellowish brown (10YR 6/4) very stony coarse sandy loam, dark yellowish brown (10YR 3/4) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine, common fine, common medium, and common coarse roots; common fine interstitial and tubular pores; 25 percent gravel, 10 percent cobbles, and 20 percent stones; slightly acid; clear wavy boundary. (7 to 20 inches thick)
Bw2--22 to 27 inches; light yellowish brown (10YR 6/4) very stony coarse sandy loam, dark yellowish brown (10YR 4/4) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine, common fine, common medium, and common coarse roots; common fine interstitial and tubular pores; 25 percent gravel, 10 percent cobbles, and 20 percent stones; slightly acid; abrupt wavy boundary. (5 to 15 inches thick)
C--27 to 49 inches; light yellowish brown (10YR 6/4) extremely stony coarse sandy loam, dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; common fine, common medium, and common coarse roots; common very fine and fine interstitial and tubular pores; common medium distinct dark reddish brown (5YR 3/4) moist irregular masses of iron accumulation in the matrix; 45 percent gravel, 10 percent cobbles, and 15 percent stones; slightly acid; abrupt irregular boundary. (10 to 24 inches thick)
R--49 inches; hard granitic rock.
TYPE LOCATION: Alpine County, California; on the Toiyabe National Forest about 1,500 feet south-southeast of Hope Valley Campground; approximately 2,300 feet north and 1,000 feet west of the southeast corner of section 7, T. 10 N., R. 19 E.; USGS Carson Pass 7.5 minute topographic quadrangle; 38 degrees 43 minutes 37.9 seconds north latitude and 119 degrees 55 minutes 33.2 seconds west longitude, NAD27.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually moist in the moisture control section; moist fall, winter, and spring; usually dry July through early October; saturated within 40 inches of the soil surface, in horizons above the bedrock, for greater than 20 consecutive days during the spring or early summer; Xeric moisture regime.
Mean annual soil temperature - 44 to 47 degrees F.
Mean summer soil temperature - 59 to 62 degrees F.
Umbric epipedon thickness - 10 to 17 inches.
Depth to bedrock - 40 to 60 inches to a lithic contact.
Particle-size control section - Clay content: Averages 12 to 18 percent; Rock fragments: Averages 35 to 60 percent. Lithology of fragments are granitic rocks such as granodiorite and volcanic rocks such as andesite.
A horizons - Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 2 to 4 percent.
Reaction: Moderately acid or slightly acid.
Bw horizons - Hue: 10YR or 7.5YR.
Value: 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Texture: Very stony coarse sandy loam or very stony sandy loam.
Clay content: 10 to 18 percent.
Rock fragments: 35 to 60 percent.
Reaction: Moderately acid or slightly acid.
C horizon - Hue: 10YR or 7.5YR.
Value: 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Texture: Extremely stony coarse sandy loam or very stony sandy loam.
Clay content: 12 to 18 percent.
Rock fragments: 50 to 80 percent.
Reaction: Moderately acid or slightly acid.
Redoximorphic features: Redox concentrations occur as masses of iron accumulation.
COMPETING SERIES: There are currently no other series in this family.
GEOGRAPHIC SETTING: Alpineco soils are on mountains. They typically occur on shoulder and backslope positions. They formed in till derived from mixed rocks and colluvium derived mainly from granitic rocks. Slopes are 8 to 75 percent. Elevations range from 7,000 to 8,000 feet. The climate is subhumid-continental with cold, moist winters and cool, dry summers. The mean annual precipitation is 30 to 45 inches, the mean annual temperature is 39 to 45 degrees F., and the frost-free period is 40 to 70 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Burnlake and Hardtil soils. Burnlake soil are very deep and occur on moraines. Hardtil soils are shallow to lithic contacts.
DRAINAGE AND PERMEABILITY: Moderately well drained; medium or high surface runoff; moderately rapid permeability (high saturated hydraulic conductivity). Endosaturation is present with an apparent seasonal high water table occurring somewhere between 24 and 40 inches (moderately deep free water occurrence class) from April to June. Cumulative annual duration class is Transitory. The water table only occurs in spring and early summer during melting of winter snowpack when water moves laterally above the bedrock.
USE AND VEGETATION: Alpineco soils are used for forest land, recreation, watershed, and wildlife habitat. The native vegetation is mainly a forest canopy of lodgepole pine, Jeffrey pine, and Sierra juniper with an understory of snowberry and bluegrass.
DISTRIBUTION AND EXTENT: Eastern California, on the east side of the Sierra Nevada Range. These soils are not extensive with about 1,800 acres of the series mapped to date. MLRA 22A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Alpine County (Toiyabe National Forest Area), California, 2006.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Umbric epipedon - The zone from the soil surface to 12 inches (A1 and A2 horizons).
Cambic horizon - The zone from 12 to 27 inches (Bw1 and Bw2 horizons).
Endosaturation feature - The condition of ground water with an upper boundary between 24 and 40 inches at certain times during normal years (parts of the Bw2 and C horizons).
Lithic contact - The boundary at 49 inches to underlying hard bedrock (R layer).
Particle-size control section - The zone from 10 to 40 inches (Bw1 and Bw2 horizons and part of the A2 and C horizons).