LOCATION EARLAL CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, magnesic, mesic Lithic Haploxeralfs
TYPICAL PEDON: Earlal very gravelly loam, on a south facing 20 percent slope under a cover of foothill pine, whiteleaf manzanita, blue oak, buckbrush, and canyon live oak at an elevation of 2305 feet, (703 m). When described on 10/19/2000 the soil was dry to 3 inches and very slightly moist below. (Colors are for dry soil unless otherwise noted).
A--0 to 3 inches, (0 to 8 cm); brown (7.5YR 5/3) very gravelly loam, dark brown (7.5YR 3/2) moist; 25 percent clay; moderate fine granular structure; slightly hard, friable, slightly sticky, slightly plastic; many very fine and fine roots and few medium roots; many very fine, fine and medium irregular and tubular pores; 10 percent cobbles and 25 percent gravel; neutral, pH 7.2 by Hellige-Truog; clear smooth boundary. (1 to 3 inches, (3 to 8 cm) thick)
Bt1--3 to 7 inches, (8 to 18 cm); brown (7.5YR 5/3) very gravelly clay loam, brown (7.5YR 4/2) moist; 34 percent clay; moderate fine and medium subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; many very fine, fine and medium roots; many very fine, fine and medium tubular pores; 60 percent continuous distinct clay films; 20 percent cobbles and 25 percent gravel; neutral, pH 7.0 by Hellige-Truog; gradual smooth boundary.
Bt2--7 to 14 inches, (18 to 36 cm); brown (7.5YR 5/4) extremely gravelly clay loam, dark brown (7.5YR 3/3) moist; 37 percent clay; moderate fine and medium subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; many very fine, fine and medium roots and common coarse roots; many very fine, fine and medium tubular pores; 80 percent continuous distinct clay films; 35 percent cobbles and 40 percent gravel; neutral, pH 7.0 by Hellige-Truog; abrupt wavy boundary. (Combined thickness of the Bt horizon is 7 to 19 inches, (18 to 48 cm) thick).
R--14 inches, (36 cm); Indurated serpentinite bedrock.
TYPE LOCATION: Butte County, California, about 1.12 miles east of Concow School, approximately 1250 feet north and 550 feet west of the southeast corner of Section 27, Township 22 N., Range 4 E.; 39 degrees 43 minutes, 47 seconds North latitude and 121 degrees, 30 minutes, 26 seconds West longitude, NAD83 - U.S.G.S Quad: Cherokee, California.
RANGE IN CHARACTERISTICS: Depth to lithic bedrock is 10 to 20 inches, (25 to 51 cm). The mean annual soil temperature is 57 to 59 degrees F, (14 to 15 degrees C). The particle-size control section averages 27 to 35 percent clay and 50 to 70 percent rock fragments, mostly gravel and cobbles. Mineralogy is magnesic. Rock fragments on the surface range from 20 to 50 percent gravel, 20 to 30 percent cobbles, 10 to 20 percent stones and 5 to 15 percent boulders.
The A horizon dry color is 7.5YR 5/3, 6/3, 6/4 or 10YR 6/4. Moist color is 7.5YR 3/2, 3/3, 3/4 or 10YR 4/3. Texture is very gravelly loam, extremely gravelly loam, very cobbly loam or very stony loam. Clay content ranges from 18 to 27 percent. Rock fragments range from 20 to 50 percent gravel, 10 to 25 percent cobbles, 0 to 10 percent stones and to 0 to 10 percent boulders. Reaction is slightly acid to neutral.
The Bt horizon dry color is 5YR 5/3, 5/4, 6/4, 7.5YR 6/4 or 10YR 7/4. Moist color is 5YR 3/3, 4/2, 7.5YR 3/4, 4/3, 4/4, 4/6, 10YR 4/3, 4/4 or 5/4. Texture is very gravelly clay loam, extremely gravelly clay loam, very cobbly clay loam, extremely cobbly clay loam or very gravelly loam. Clay content ranges from 24 to 40 percent. Rock fragments range from 20 to 40 percent gravel, 20 to 40 percent cobbles, 0 to 10 percent stones and to 0 to 10 percent boulders. Reaction is slightly acid to neutral.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Earlal soils are on ridge tops and side slopes on ultramafic Sierra Nevada mountains. Slopes range from 3 to 80 percent. These soils formed in residuum and colluvium weathered from serpentinized ultramafic rocks. Elevation is 900 to 3600 feet, (274 to 1097 m). Mean annual precipitation is 42 to 65 inches, (1067 to 1651 m). The mean annual temperature is 55 to 58 degrees F, (13 to 14 degrees C). Frost free season is 185 to 250 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cerpone, Boxrobber and Millerridge soils. Cerpone soils are fine-loamy and deep to bedrock. Boxrobber and Millerridge soils have mixed mineralogy and are underlain by paralithic contacts of partially serpentinized ultramafic bedrock.
DRAINAGE AND PERMEABILITY: Well drained; very high runoff; moderate saturated hydraulic conductivity in the A horizon and moderately slow in the Bt horizon.
USE AND VEGETATION: This soil is used for wildlife habitat, watershed and some home site development. Vegetation is whiteleaf manzanita, foothill pine, buckbrush, canyon liveoak, California laurel, blue oak, and toyon. ponderosa pine, Jeffery pine, incense cedar, Douglas-fir, and California black oak grow at higher elevation.
DISTRIBUTION AND EXTENT: Butte County, California and occur in the M261Fb (Lower Foothills Metamorphic Belt) subsection of the M261F (Sierra Nevada Foothills) section. MLRA 22A - Sierra Nevada Range. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Butte County, California 2005. Source of name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle-size control section - zone from 0 to 14 in, (0 to 36 cm)
Ochric epipedon - zone from 0 to 3 in, (0 to 8 cm) (A)
Argillic horizon - zone from 3 to 14 in, (8 to 36 cm) (Bt1, Bt2)
Lithic contact -14 inches, (36 cm)
The soil moisture control section - zone from 10 to 14 inches, (25 to 36 cm) is dry in all parts from about June to October (about 150 days).