LOCATION CLOUDBURST CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Ultic Haploxeralfs
TYPICAL PEDON: Cloudburst extremely bouldery coarse sandy loam--forestland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 25 percent gravel, 5 percent cobbles, 5 percent stones, and 7 percent boulders.
A1--0 to 3 inches; dark grayish brown (10YR 4/2) extremely bouldery coarse sandy loam, very dark brown (10YR 2/2) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine roots; many very fine interstitial pores; 25 percent gravel, 20 percent stones, and 20 percent boulders; slightly acid; clear smooth boundary. (2 to 5 inches thick)
A2--3 to 8 inches; dark grayish brown (10YR 4/2) extremely bouldery coarse sandy loam, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine through very coarse roots; many very fine tubular and interstitial pores; 25 percent gravel, 20 percent stones, and 20 percent boulders; slightly acid; clear wavy boundary. (4 to 7 inches thick)
Bt1--8 to 16 inches; grayish brown (10YR 5/2) extremely bouldery coarse sandy loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; many very fine through very coarse roots; many very fine tubular and interstitial pores; few faint clay bridges between sand grains; 20 percent gravel, 15 percent cobbles, 20 percent stones, and 20 percent boulders; slightly acid; clear wavy boundary. (4 to 8 inches thick)
Bt2--16 to 29 inches; pale brown (10YR 6/3) extremely bouldery sandy clay loam, brown (10YR 4/3) moist; moderate fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine, many fine, many medium, and many coarse roots; common very fine tubular and interstitial pores; common faint clay bridges between sand grains; 20 percent gravel, 15 percent cobbles, 20 percent stones, and 20 percent boulders; slightly acid; clear wavy boundary. (10 to 20 inches thick)
Bt3--29 to 38 inches; pale brown (10YR 6/3) extremely cobbly coarse sandy loam, brown (10YR 4/3) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; common very fine and common fine roots; common very fine tubular and interstitial pores; few faint clay bridges between sand grains; 30 percent gravel, 30 percent cobbles, and 10 percent stones; neutral; clear wavy boundary. (8 to 14 inches thick)
Bt4--38 to 60 inches; pale brown (10YR 6/3) extremely cobbly coarse sandy loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common very fine, few fine, few medium, and few coarse roots; common very fine tubular and interstitial pores; few faint clay bridges between sand grains; 30 percent gravel, 30 percent cobbles, and 10 percent stones; slightly acid.
TYPE LOCATION: Mono County, California; on the Toiyabe National Forest about 2 miles west-northwest of the Marine Mountain Warfare Training Center; approximately 900 feet north and 600 feet west of the southeast corner of section 15, T. 6 N, R. 22 E.; USGS Pickel Meadow 7.5 minute topographic quadrangle; 38 degrees 21 minutes 47.1 seconds north latitude and 119 degrees 32 minutes 44.7 seconds west longitude, NAD27.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually moist in the moisture control section during late fall, winter, and spring; dry from mid-July through September for 60 to 80 consecutive days in the four months following the summer solstice; Typic xeric moisture regime.
Mean annual soil temperature - 44 to 47 degrees F.
Umbric epipedon thickness - 10 to 16 inches; includes the Bt1 horizon.
Depth to base of argillic horizon - 40 to more than 60 inches.
Particle-size control section - Clay content: Averages 18 to 25 percent; Rock fragments: Averages 60 to 80 percent, mainly greater than 3 inches in diameter (boulders, stones, and cobbles). Lithology of fragments are mixed igneous and metamorphic rocks such as granodiorite, andesite, schist, and gneiss.
A horizons - Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 3 to 5 percent.
Reaction: Slightly acid or neutral.
Bt1 horizon - Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Texture: Extremely bouldery coarse sandy loam or extremely cobbly sandy clay loam.
Clay content: 15 to 25 percent.
Rock fragments: 60 to 80 percent.
Organic matter content: 1 to 3 percent.
Reaction: Slightly acid or neutral.
Bt2 and Bt3 horizons - Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4, dry or moist.
Texture: Extremely bouldery sandy clay loam or extremely cobbly coarse sandy loam.
Clay content: 18 to 25 percent.
Rock fragments: 60 to 80 percent.
Reaction: Slightly acid or neutral.
Bt4 horizon - Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4, dry or moist.
Texture: Extremely cobbly coarse sandy loam or extremely bouldery sandy loam.
Clay content: 12 to 18 percent.
Rock fragments: 60 to 80 percent.
Reaction: Slightly acid or neutral.
COMPETING SERIES: These are the Chapot and Euer series.
Chapot soils have ochric epipedons, are influenced by volcanic ash in the A horizons, and have less than 60 percent rock fragments in the particle-size control section. Euer soils are dominated by gravel in the particle-size control section.
GEOGRAPHIC SETTING: Cloudburst soils are on moraines. They typically occur on footslope positions. They formed in till derived from igneous and metamorphic rocks such as granodiorite, andesite, schist, and gneiss. Slopes are 8 to 50 percent. Elevations range from 7,000 to 8,300 feet. The climate is subhumid-continental with cold, moist winters and warm, dry summers. The mean annual precipitation is 18 to 30 inches, 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 Aspetill and Murain soils. Aspetill soils have mollic epipedons and a cryic temperature regime. Murain soils have mollic epipedons.
DRAINAGE AND PERMEABILITY: Well drained; low or medium surface runoff; moderate permeability (moderately high or high saturated hydraulic conductivity).
USE AND VEGETATION: Cloudburst soils are used for forestland, recreation, watershed, and wildlife habitat. The native vegetation is mainly a forest canopy of Jeffrey pine and Sierra juniper with an understory of snowbrush ceanothus, snowberry, mountain big sagebrush, antelope bitterbrush, and western needlegrass.
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: Mono 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 16 inches (A1, A2, and Bt1 horizons).
Argillic horizon - The zone from 8 to 60 inches (Bt1, Bt2, Bt3, and Bt4 horizons).
Particle-size control section - The zone from 8 to 28 inches (Bt1 horizon and part of the Bt2 horizon).