LOCATION COWBELL CA+NVEstablished Series
TAXONOMIC CLASS: Ashy-skeletal, glassy Vitrandic Argicryolls
TYPICAL PEDON: Cowbell extremely cobbly ashy mucky sandy loam--mahogany savanna. (Colors are for dry soil unless otherwise noted). About 40 percent of the soil surface is covered by a thin layer of leaves and twigs.
A1--0 to 3 inches; very dark grayish brown (10YR 3/2) extremely cobbly ashy mucky sandy loam, black (10YR 2/1) moist; moderate medium subangular blocky structure parting to moderate medium granular; soft, very friable, nonsticky and nonplastic; many very fine and fine and common medium and coarse roots; many very fine interstitial pores; 15 percent stones, 30 percent cobbles, and 20 percent gravel; moderately acid (pH 6.0); clear smooth boundary. (2 to 5 inches thick)
A2--3 to 9 inches; dark grayish brown (10YR 4/2) extremely cobbly ashy loam, very dark brown (10YR 2/2) moist; moderate medium and coarse subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; many very fine and fine and common medium and coarse roots; many very fine and fine tubular pores; 10 percent stones, 30 percent cobbles, and 25 percent gravel; slightly acid (pH 6.2); clear wavy boundary. (6 to 13 inches thick)
Bt1--9 to 20 inches; dark grayish brown (10YR 4/2) extremely cobbly ashy loam, very dark brown (10YR 2/2) moist; moderate medium and coarse subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; many very fine to coarse roots; many very fine and few fine tubular pores; common distinct clay films on faces of peds and lining pores; 5 percent stones, 35 percent cobbles, and 30 percent gravel; neutral (pH 6.6); abrupt irregular boundary. (10 to 18 inches thick)
Bt2--20 to 40 inches; brown (7.5YR 5/4) very cobbly ashy sandy clay loam, dark brown (7.5YR 3/4) moist; moderate medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few very fine and fine, and common medium and coarse roots; many very fine and few fine tubular pores; many distinct clay films on faces of peds and lining pores; 25 percent cobbles and 30 percent gravel; neutral (pH 6.8); clear wavy boundary. (10 to 18 inches thick)
Bt3--40 to 60 inches; pale brown (10YR 6/3) very gravelly ashy sandy clay loam, dark grayish brown (10YR 4/2) moist; weak coarse subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few very fine to medium roots; common very fine and few fine tubular pores; common distinct clay films on faces of peds and lining pores; 5 percent cobbles and 35 percent gravel; neutral (pH 6.8).
TYPE LOCATION: Lassen County, California; in the Cottonwood Mountains about 3 miles southeast of Dodge Reservoir; approximately 1,900 feet west and 400 feet north of the southeast corner of section 20, T. 36 N., R. 17 E.; USGS Buckhorn Lake 7.5 minute topographic quadrangle; 40 degrees 57 minutes 57.3 seconds north latitude and 120 degrees 03 minutes 42.9 seconds west longitude, NAD83.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually moist in winter and spring, dry in late summer and fall; completely dry for at least 45 consecutive days between July and October; Xeric moisture regime that borders on aridic.
Mean annual soil temperature - 41 to 44 degrees F.
Mean summer soil temperature - 54 to 59 degrees F.
Mollic epipedon thickness - 16 to 30 inches; includes the Bt1 horizon.
Volcanic glass content - 50 to 80 percent in the coarse silt through fine sand fractions.
Particle-size control section - Clay content: 18 to 25 percent;
Rock fragments: 50 to 70 percent, dominantly cobbles and gravel. Lithology of fragments are volcanic rocks such as basalt and andesite.
A1 horizon
Value: 3 or 4 dry, 2 or 3 moist.
Chroma: 1 through 4, dry or moist.
Reaction: Slightly acid or neutral.
Organic matter content: 10 to 16 percent.
A2 horizon
Value: 3 or 4 dry, 2 or 3 moist.
Chroma: 1 through 4, dry or moist.
Reaction: Slightly acid or neutral.
Organic matter content: 1 or 2 percent.
Bt horizons
Value: 4 through 6 dry.
Chroma: 2 through 4, dry or moist.
Structure: Angular blocky or subangular blocky.
Consistence: Slightly hard or hard dry.
Organic matter content: 0.5 to 2 percent.
COMPETING SERIES: These are the Ashflat, Boulderfan, Euell, Fendersflat, Hardshoulder, Lastsummer, Paynepeak, Pyropatti, Snag, and Tusune series.
Ashflat, Paynepeak, and Snag soils have a mollic epipedon greater than 30 inches thick. Boulderfan soils have an apparent water table at depths of 3.5 to 5 feet. Euell soils are deep to lithic contacts and have an ustic moisture regime. Fendersflat and Tusune soils are moderately deep to paralithic contacts. Hardshoulder soils have accumulations of secondary silica. Lastsummer soils have less than 18 percent clay in the particle-size control section and have accumulations of secondary silica. Pyropatti soils soils are deep to paralithic contacts.
GEOGRAPHIC SETTING: Cowbell soils are on mountains and plateaus. They typically occur on summit and shoulder positions. These soils formed in colluvium derived from basalt, andesite, tuff, and volcanic ash. Slopes are 4 to 50 percent. Elevations range from 5,260 to 9,000 feet. The mean annual precipitation is 14 to 18 inches, the mean annual temperature is 39 to 42 degrees F., and the frost-free period is 60 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brownsbowl and Redhome soils and the competing Snag soil. Brownsbowl soils do not have argillic horizons. Redhome soils are moderately deep to bedrock and have more than 35 percent clay in the control section.
DRAINAGE AND PERMEABILITY: Well drained; medium or high surface runoff; moderate permeability (moderately high or high saturated hydraulic conductivity).
USE AND VEGETATION: Livestock grazing and wildlife habitat. The present vegetation is dominantly curlleaf mountainmahogany, needlegrass, Idaho fescue, bluegrass and mountain big sagebrush.
DISTRIBUTION AND EXTENT: Northeastern California and northwestern Nevada. These soils are not extensive with about 5,400 acres of the series mapped to date. MLRA 23.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Surprise Valley-Home Camp Area, California and Nevada, 2006.
REMARKS: Diagnostic horizons and features recognized in the pedon are:
Mollic epipedon - The zone from the soil surface to 20 inches (A1, A2, and Bt1 horizons).
Argillic horizon - The zone from 9 to 60 inches (Bt1, Bt2 and Bt3 horizons).
Vitrandic intergrade feature - The zone from the soil surface to 30 inches (A1, A2, and Bt1 horizons and part of the Bt2 horizon).
Particle-size control section and ashy-skeletal substitute class with glassy mineralogy - The zone from 9 to 29 inches (Bt1 horizon and part of the Bt2 horizon).
These soils were formerly mapped as the Bluebell series.