LOCATION CAVEBEAR CAEstablished Series
TAXONOMIC CLASS: Sandy-skeletal, mixed Aquic Haplocryolls
TYPICAL PEDON: Cavebear gravelly loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered with 15 percent gravel.
A1--0 to 4 inches; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; soft, very friable, slightly sticky and nonplastic; many very fine roots; common very fine interstitial and tubular pores; 25 percent gravel; moderately acid; clear wavy boundary. (3 to 10 inches thick)
A2--4 to 13 inches; brown (10YR 5/3) gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; soft, very friable, slightly sticky and nonplastic; many very fine roots and common fine; common very fine interstitial and tubular pores; 25 percent gravel; slightly acid; clear wavy boundary. (6 to 12 inches thick)
A3--13 to 20 inches; brown (10YR 5/3) very gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common very fine and fine roots; common very fine interstitial and tubular pores; 40 percent gravel; slightly acid; clear wavy boundary. (0 to 10 inches thick)
C1--20 to 25 inches; pale brown (10YR 6/3) extremely gravelly loamy coarse sand, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 65 percent gravel; slightly acid; clear wavy boundary. (5 to 20 inches thick)
C2--25 to 60 inches; light brownish gray (10YR 6/2) extremely gravelly coarse sand, dark grayish brown (10YR 4/2) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; common coarse distinct brown (7.5YR 4/4) moist irregular masses of iron accumulation in the matrix; 70 percent gravel; slightly acid.
TYPE LOCATION: Alpine County, California; on the Toiyabe National Forest in Hope Valley about 1,800 feet east of Highway 88; approximately 5,015 feet south and 1,950 feet east of the northwest corner of section 6, T. 10 N., R. 19 E.; USGS Freel Peak 7.5 minute topographic quadrangle; 38 degrees 45 minutes 6.9 seconds north latitude and 119 degrees 56 minutes 6.9 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; Xeric moisture regime.
Mean annual soil temperature - 40 to 44 degrees F.
Mean summer soil temperature - 47 to 54 degrees F.
Mollic epipedon thickness - 16 to 24 inches.
Depth to sandy-skeletal material - 20 to 30 inches.
Depth to seasonal aquic conditions - 20 to 30 inches.
Particle-size control section - Clay content: Averages less than 10 percent; Rock fragments: Averages 35 to 60 percent, mainly gravel. Lithology of fragments are granitic rocks such as granodiorite, volcanic rocks such as tuff, or minor metamorphic rocks such as quartzite.
A1 horizon - Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 3 to 5 percent.
Reaction: Moderately acid or slightly acid.
A2 horizon and A3 horizon (when present) - Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Texture: Gravelly sandy loam or very gravelly sandy loam.
Rock fragments: 20 to 45 percent.
Organic matter content: 3 to 5 percent.
Reaction: Moderately acid or slightly acid.
C horizons - Value: 4 or 5 moist.
Chroma: 2 or 3, dry or moist.
Texture: Extremely gravelly coarse sand or extremely gravelly loamy coarse sand.
Clay content: 3 to 10 percent.
Rock fragments: 60 to 80 percent.
Reaction: Moderately acid or slightly acid.
Redoximorphic features: Redox concentrations occur as masses of iron accumulation.
COMPETING SERIES: This is the Copperbasin series. Copperbasin soils have mollic epipedons that are 10 to 15 inches thick, do not have loamy material in the upper part of the profile, and average 60 to 85 percent rock fragments in the particle-size control section.
GEOGRAPHIC SETTING: Cavebear soils are on stream terraces. They formed in alluvium derived from mixed rocks. Slopes are 2 to 8 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, 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 Burnlake and Hopeval soils. Burnlake soils are loamy-skeletal, have umbric epipedons, do not have aquic conditions, and occur on moraines. Hopeval soils are coarse-loamy and have aquic conditions within 20 inches of the soil surface.
DRAINAGE AND PERMEABILITY: Moderately well drained; low surface runoff; moderately rapid permeability (high saturated hydraulic conductivity) in the upper part of the profile over very rapid permeability (very high saturated hydraulic conductivity) in the lower part. Endosaturation is present with an apparent seasonal high water table between 20 and 30 inches (moderately deep free water occurrence class) from December through June. Cumulative annual duration classes are Common or Persistent.
USE AND VEGETATION: Cavebear soils are used for rangeland, recreation, watershed, and wildlife habitat. The native vegetation is mainly sedge, rush, and needlegrass.
DISTRIBUTION AND EXTENT: Eastern California, on the east side of the Sierra Nevada Range. These soils are not extensive with about 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:
Mollic epipedon - The zone from the soil surface to 20 inches (A1, A2, and A3 horizons).
Aquic conditions - The conditions of endosaturation and reduction between 20 and 60 inches at certain times during normal years (C1 and C2 horizons).
Particle-size control section - The zone from 10 to 40 inches (A3 and C1 horizons and parts of the A2 and C2 horizons).
The revision of December 2001 updated the taxonomic class from Sandy-skeletal, mixed Aquic Cumulic Haplocryolls. Evidence of an irregular decrease in organic carbon, such as distinct stratification, is not present.