LOCATION COALCANYON CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, parasesquic, thermic Pachic Ultic Argixerolls
TYPICAL PEDON: Coalcanyon very cobbly loam, on a west facing 45 percent slope under a cover of hardwoods, shrubs and annual grasses at an elevation of 950 feet, (290 m). When described on 6/26/2001 the soil was dry to a depth of 27 inches, (69 cm) and moist below. (Colors are for dry soil unless otherwise noted).
A--0 to 2 inches, (0 to 5 cm); brown (7.5YR 4/3) very cobbly loam, dark brown (7.5YR 3/2) moist; 16 percent clay; moderate fine granular structure; slightly hard, friable, slightly sticky, nonplastic; many very fine and fine roots; many fine irregular pores; 10 percent basalt gravel and 30 percent basalt cobbles; slightly acid, pH 6.5 by Hellige-Truog; clear wavy boundary. (2 to 7 inches, (5 to 18 cm) thick)
BAt--2 to 11 inches, (5 to 28 cm); brown (7.5YR 4/3) very cobbly loam, dark brown (7.5YR 3/2) moist; 18 percent clay; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky, nonplastic; many fine and medium roots throughout and common coarse roots between peds; many fine irregular pores; 5 percent discontinuous faint clay films on surfaces along pores; 15 percent basalt gravel and 40 percent basalt cobbles; slightly acid, pH 6.5 by Hellige-Truog; clear wavy boundary. (0 to 10 inches, (0 to 25 cm) thick)
Bt1--11 to 27 inches, (28 to 69 cm); brown (7.5YR 4/3) very cobbly loam, dark brown (7.5YR 3/2) moist; 22 percent clay; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky, slightly plastic; common fine and medium roots throughout and common coarse roots between peds; common fine and medium tubular pores; 20 percent discontinuous faint clay films on surfaces along pores; 20 percent basalt gravel and 30 percent basalt cobbles; slightly acid, pH 6.5 by Hellige-Truog; clear wavy boundary.
Bt2--27 to 43 inches, (69 to 109 cm); brown (7.5YR 4/3) very cobbly loam, dark brown (7.5YR 3/3) moist; 26 percent clay; moderate medium subangular blocky structure; slightly hard, firm, moderately sticky, slightly plastic; common very fine, fine and coarse roots between peds; common fine and medium tubular pores; 35 percent discontinuous distinct clay films on surfaces along pores; 25 percent basalt gravel and 35 percent basalt cobbles; moderately acid, pH 6.0 by Hellige-Truog; clear wavy boundary.
Bt3--43 to 65 inches, (109 to 165 cm); reddish brown (5YR 4/3) extremely cobbly clay loam, dark reddish brown (5YR 3/3) moist; 29 percent clay; moderate medium subangular blocky structure; slightly hard, firm, moderately sticky, moderately plastic; common very fine and fine roots between peds; common fine tubular pores; 50 percent discontinuous distinct clay films on surfaces along pores; 20 percent basalt gravel and 50 percent basalt cobbles; moderately acid, pH 6.0 by Hellige-Truog; clear wavy boundary. (Combined thickness of the Bt horizon is 50 to 80 inches, (127 to 203 cm) or more thick).
TYPE LOCATION: Butte County, California, about 5.7 miles northwest of Oroville, approximately 1500 feet east and 1300 feet south of the northwest corner of Section 13, Township 20 N., Range 3 E., 39 degrees, 35 minutes, 35 seconds North latitude and 121 degrees, 35 minutes, 23 seconds West longitude, NAD27 - U.S.G.S. Quad: Oroville, California.
RANGE IN CHARACTERISTICS: Depth of to bedrock is greater than 60 inches, (152 cm). The mean annual soil temperature is 61 to 64 degrees F, (16 to 18 degrees C). The particle-size control section averages 18 to 27 percent clay and 35 to 60 percent rock fragments, mostly gravel and cobbles. Mineralogy is mixed. Organic matter ranges from 1 to 13 percent to a depth of 43 inches, (3 to 109 cm) and is less than 1 percent below. Base saturation by ammonium acetate ranges from 78 to 91 percent throughout. Base saturation by sum of cations ranges from 55 to 58 percent throughout. Rock fragments on the surface range from 10 to 60 percent gravel, 5 to 65 percent cobbles, 0 to 25 percent stones and 0 to 20 percent boulders. Some pedons have silty textures throughout.
The A horizon dry color is 10YR 3/3, 3/4, 4/2, 4/3, 4/4 or 7.5YR 4/3. Moist color is 10YR 2/2, 3/2, 3/3 or 7.5YR 3/2. Texture is very cobbly loam, very gravelly loam or gravelly loam. Clay content ranges from 14 to 18 percent. Rock fragments range from 10 to 55 percent gravel, 5 to 35 percent cobbles, 0 to 45 percent stones and 0 to 15 percent boulders. Reaction ranges from slightly acid to neutral.
The BAt horizon dry color is 10YR 4/2, 4/3, 7.5YR 4/3 or 4/4. Moist color is 10YR 2/2, 3/2, 3/3, 7.5YR 3/2 or 3/3. Texture is very cobbly loam or very gravelly loam. Clay content ranges from 16 to 22 percent. Rock fragments range from 15 to 50 percent gravel, 5 to 40 percent cobbles, 0 to 55 percent stones and 0 to 15 percent boulders. Reaction ranges from slightly acid to neutral.
The Bt horizon dry color is 10YR 4/3, 4/4, 4/6, 5/3, 5/4, 7.5YR 4/3 or 5YR 4/3. Moist color is 10YR 3/2, 3/3, 3/4, 4/4, 7.5YR 3/2 or 3/3. Texture is very cobbly loam, extremely cobbly loam, very cobbly clay loam, extremely cobbly clay loam, extremely gravelly loam or extremely gravelly clay loam. Clay content ranges from 22 to 35 percent. Rock fragments range from 20 to 80 percent gravel, 5 to 50 percent cobbles, 0 to 60 percent stones and 0 to 15 percent boulders. Reaction ranges from moderately acid to neutral.
COMPETING SERIES: This is the Coonhollow soil. Coonhollow soils are deep to a paralithic contact.
GEOGRAPHIC SETTING: Coalcanyon soils are on side slopes on basalt plateaus in volcanic Sierra Nevada foothills. Slopes range from 5 to 50 percent. These soils formed in colluvium weathered from basalt. Elevation is 200 to 1500 feet, (61 to 457 m). The mean annual precipitation is 25 to 35 inches, (635 to 889 mm). The mean annual temperature is 59 to 62 degrees F, (15 to 17 degrees C). Frost free season is 250 to 260 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Beatsonhollow, Campbellhills, Cherotable, Coonhollow, and Thermalrocks soils. Beatsonhollow soils are in swales in a mound-swale microtopography on basalt plateaus, are loamy-skeletal and shallow to bedrock. Campbellhills soils are in fractures on basalt plateaus, are loamy-skeletal and deep to bedrock. Cherotable soils are on concave positions on basalt plateaus, are fine loamy and deep to bedrock. Coonhollow soils are deep to a paralithic contact. Thermalrocks soils are on convex positions on basalt plateaus, are loamy-skeletal and very shallow to bedrock.
DRAINAGE AND PERMEABILITY: Well drained; low to medium runoff; moderate saturated hydraulic conductivity in the A and BAt horizons and moderate to moderately slow in the Bt horizon.
USE AND VEGETATION: This soil is used for livestock grazing, wildlife habitat and watershed. Vegetation is live oak, blue oak, valley oak, foothill pine, whiteleaf manzanita, toyon, California laurel, Pacific poison oak, mustard, hedgehog dogstail, wild oat, soft chess, filaree, yellow starthistle and rose clover.
DISTRIBUTION AND EXTENT: Butte County, California and occurs in (M261Fb) Lower Foothills Metamorphic Belt subsection of the (M261 F) Sierra Nevada Foothills section. MLRA: 18 -- Sierra Nevada Foothills. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Butte County, California 2005. Source of name from Coal Canyon on the Oroville Quad.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle-size control section - zone from 11 to 33 in, (28 to 84 cm)
Mollic epipedon - zone from 0 to 43 in, (0 to 109 cm) (A, BAt, Bt1, Bt2)
Argillic horizon - zone from 11 to 65 in, (28 to 165 cm) (Bt1, Bt2, Bt3)
The soil moisture control section - zone from 13 to 38 inches, (33 to 96 cm) is dry in all parts from about May to October (about 150 to 200 days).
ADDITIONAL DATA: Used data from Coonhollow SO1CA-007-007 NSSL, Lincoln, NE.