LOCATION HARGRAN CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Oxyaquic Humicryepts
TYPICAL PEDON: Hargran stony coarse sandy loam--forest land. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered with 10 percent gravel, 10 percent cobbles, 1 percent stones, and 10 percent boulders.
Oe--0 to 1 inch; dark grayish brown (10YR 4/2) stony moderately decomposed plant material, very dark brown (10YR 2/2) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine and few fine roots; common very fine interstitial and tubular pores; fiber content is about 70 percent before rubbing and about 50 percent after rubbing; 10 percent gravel and 10 percent stones; very strongly acid; clear wavy boundary. (0 to 2 inches thick)
A1--1 to 9 inches; grayish brown (10YR 5/2) stony coarse sandy loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine, many fine, many medium, and many coarse roots; common very fine interstitial and tubular pores; 10 percent gravel and 10 percent stones; very strongly acid; clear wavy boundary. (2 to 11 inches thick)
A2--9 to 24 inches; yellowish brown (10YR 5/4) stony sandy loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine, few fine, many medium, and many coarse roots; common very fine interstitial and tubular pores; 15 percent gravel, 5 percent cobbles, and 10 percent stones; very strongly acid; clear wavy boundary. (5 to 16 inches thick)
Bw1--24 to 36 inches; brown (7.5YR 5/4) very stony sandy loam, dark brown (7.5YR 3/4) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine to coarse roots; common very fine interstitial and tubular pores; 25 percent gravel, 5 percent cobbles, and 10 percent stones; strongly acid; clear irregular boundary. (8 to 14 inches thick)
Bw2--36 to 39 inches; yellowish brown (10YR 5/4) very stony sandy loam, dark yellowish brown (10YR 3/4) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine to coarse roots; common very fine interstitial and tubular pores; 25 percent gravel, 5 percent cobbles, and 10 percent stones; common medium distinct yellowish red (5YR 4/6) moist masses of iron accumulation in the matrix; strongly acid; abrupt irregular boundary. (3 to 6 inches thick)
R--39 inches; hard granitic bedrock.
TYPE LOCATION: Alpine County, California; on the Eldorado National Forest about 0.75 mile northeast of Lower Blue Lake; approximately 2,460 feet south and 400 feet east of the northwest corner of section 20, T. 9 N., R. 19 E.; USGS Pacific Valley 7.5 minute topographic quadrangle; 38 degrees 37 minutes 09 seconds north latitude and 119 degrees 55 minutes 01 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 a 3 to 10 inch thick zone directly overlying bedrock (within depths of 24 to 40 inches) for greater than 20 consecutive days during the spring or early summer; Typic xeric moisture regime.
Mean annual soil temperature - 40 to 44 degrees F.
Mean summer soil temperature - 44 to 47 degrees F.
Umbric epipedon thickness - 16 to 24 inches; includes the A1 and A2 horizons.
Depth to bedrock - 20 to 40 inches to a lithic contact measured from the boundary between the Oe and A1 horizons.
Particle-size control section - Clay content: Averages 10 to 18 percent; Rock fragments: Averages 35 to 50 percent, mainly stones. Lithology of fragments are granitic rock such as granodiorite.
A horizons
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 through 4 dry, 2 or 3 moist.
Organic matter content: 3 to 5 percent.
Reaction: Very strongly acid or strongly acid.
Bw horizons
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 4 through 8 dry, 4 through 6 moist.
Texture: Very stony sandy loam or very gravelly coarse sandy loam.
Clay content: 10 to 18 percent.
Rock fragments: 35 to 50 percent.
Reaction: Very strongly acid or strongly acid.
Redoximorphic features: Redox concentrations occur as masses of iron accumulation within the matrix in the Bw2 horizon.
COMPETING SERIES: There are currently no other series in this family.
GEOGRAPHIC SETTING: Hargran soils are on mountains. They typically occur on concave shoulder positions. These soils formed in till derived from mixed rocks and colluvium derived from granitic rock. Slopes are 8 to 30 percent. Elevations range from 8,000 to 9,000 feet. The climate is subhumid-continental with cold, moist winters and cool, dry summers. The mean annual precipitation is 35 to 55 inches, mean annual temperature is 35 to 40 degrees F., and the frost-free period is 30 to 60 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Granylith and Klauspeak soils. Granylith soils are sandy-skeletal, shallow to lithic contacts, and have ochric epipedons. Klauspeak soils are sandy-skeletal and very deep.
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 between 24 and 40 inches (moderately deep free water occurrence class) in a 3 to 10 inch zone from April to June. Cumulative annual duration class is Transitory. The water table only occurs during spring and early summer following melting of winter snowpack when water moves laterally above the bedrock.
USE AND VEGETATION: Hargran soils are used for forest land, recreation, watershed, and wildlife habitat. The native vegetation is a forest canopy of mainly California red fir, lodgepole pine, western white pine, white fir and mountain hemlock with an understory of sedge, bluegrass spp., and various forbs.
DISTRIBUTION AND EXTENT: Eastern California, on the east side of the Sierra Nevada Range. These soils are not extensive with about 2,400 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:
Organic soil material - The zone from the soil surface to 1 inch (Oe horizon).
Umbric epipedon - The zone from 1 to 24 inches (A1 and A2 horizons).
Cambic horizon - The zone from 24 to 39 inches (Bw1 and Bw2 horizons).
Aquic conditions - The conditions of endosaturation, reduction, and redoximorphic features present in the zone above the bedrock contact during spring of most years (Bw2 horizon).
Lithic contact - The boundary at 39 inches to underlying hard bedrock (R layer).
Particle-size control section - The zone from 10 to 39 inches (Bw1 and Bw2 horizons and part of the A2 horizon).
The revision of December 2006 updated the taxonomic class from Oxyaquic Dystrocryepts based on the tenth edition of the Keys to Soil Taxonomy, 2006.
ADDITIONAL DATA: The typical pedon at the series type location is sampled for the Soil Survey Laboratory (SSL), Lincoln, NE as soil survey sample number S99CA-003-001 (pedon # 00P0464).