LOCATION SUNNYSLOPE CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic, shallow Ultic Haploxeralfs
TYPICAL PEDON: Sunnyslope loam, on a north facing 7 percent slope under a cover of blue oak, wild oat, rattlesnake brome, Italian ryegrass, red clover, dandelion and wild onion at an elevation of 215 feet, (65 m). When described on 7/30/2001 the soil was dry throughout. (Colors are for dry soil unless otherwise noted)
A--0 to 2 inches, (0 to 5 cm); strong brown (7.5YR 5/6) loam, dark brown (7.5YR 3/3) moist; 17 percent clay; moderate very fine and fine subangular blocky structure; moderately hard, very friable, slightly sticky, slightly plastic; many very fine roots; common fine and many very fine tubular pores; 2 percent subangular quartz gravel and 10 percent subangular gravel; slightly acid, pH 6.5 by Hellige-Truog; abrupt smooth boundary. (1 to 4 inches, (3 to 10 cm) thick)
Bt1--2 to 6 inches, (5 to 15 cm); strong brown (7.5YR 5/6) gravelly loam, dark reddish brown (5YR 3/4) moist; 20 percent clay; strong fine and medium subangular blocky structure; moderately hard, very friable, slightly sticky, slightly plastic; many very fine roots; common fine and many very fine tubular pores; 4 percent patchy faint clay films on faces of peds; 15 percent subangular gravel; slightly acid, pH 6.5 by Hellige-Truog; gradual wavy boundary. (4 to 7 inches, (10 to 18 cm) thick)
Bt2--6 to 10 inches, (15 to 25 cm); yellowish red (5YR 4/6) very cobbly loam, reddish brown (5YR 4/4) moist; 25 percent clay; strong fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky, slightly plastic; common fine and many very fine roots; few fine and many very fine tubular pores; 25 percent patchy faint clay films on faces of peds; 35 percent subangular gravel and 25 percent subangular cobbles; slightly acid, pH 6.3 by Hellige-Truog; clear wavy boundary. (4 to 6 inches, (10 to 15 cm) thick)
Bt3--10 to 14 inches, (25 to 36 cm); yellowish red (5YR 4/6) extremely gravelly clay loam, reddish brown (5YR 4/4) moist; 29 percent clay; strong very fine and fine subangular blocky structure; moderately hard, friable, slightly sticky, slightly plastic; few medium roots and common very fine roots; few fine and many very fine tubular pores; 25 percent patchy faint clay films on faces of peds; 70 percent subangular gravel; slightly acid, pH 6.3 by Hellige-Truog; clear wavy boundary. (4 to 6 inches, (10 to 15 cm) thick)
Crt--14 to 21 inches, (36 to 53 cm); moderately cemented greenschist bedrock; yellowish red (5YR 5/8), yellowish red (5YR 4/6) moist; few very fine, fine and coarse roots top of horizon; slightly acid, pH 6.5 by Hellige-Truog.
TYPE LOCATION: Butte County, California; about 4 miles southeast of Palermo, California, approximately 600 feet north and 1250 feet east of the southwest corner of Section 22, Township 18 N., Range 4 E., 39 degrees, 23 minutes, 47.10 seconds North latitude; 121 degrees, 30 minutes, 57.59 seconds West longitude. NAD83-U.S.G.S. Quad: Palermo, California.
RANGE IN CHARACTERISTICS: Depth to paralithic bedrock is 10 to 20 inches, (25 to 51 cm). The mean annual soil temperature is 59 to 65 degrees F, (15 to 18 degrees C). The soil moisture control section is dry in all parts from about June 1 to October 15 (about 150 days). The particle-size control section averages 15 to 25 percent clay and 35 to 50 percent rock fragments, mostly gravel. Mineralogy is mixed. Rock fragments on the surface range from 0 to 10 percent gravel, 0 to 15 percent cobbles and 0 to 5 percent stones.
The A horizon dry color is 7.5YR 4/6, 5/4 or 5/6. Moist color is 7.5YR 3/3 or 3/4. Texture is loam. Clay content ranges from 10 to 18 percent. Rock fragments range from 2 to 12 percent gravel. Organic matter ranges from 3 to 7 percent. Base saturation by sum of cations ranges from 65 to 75 percent. Reaction is slightly acid.
The upper Bt horizon dry color is 7.5YR 5/6, 6/4 or 5YR 5/6. Moist color is 7.5YR 4/4 or 5YR 3/4. Texture is loam, gravelly loam or very gravelly loam. Clay content ranges from 15 to 20 percent. Rock fragments range from 15 to 35 percent gravel. Organic matter ranges from 1 to 4 percent. Base saturation by sum of cations ranges from 65 to 75 percent. Reaction ranges from moderately acid to slightly acid.
The lower Bt horizon dry color is 5YR 4/6, 5/6 or 7.5YR 5/4. Moist color is 5YR 4/3 or 4/4. Texture is very gravelly loam, extremely gravelly loam, very cobbly loam or extremely gravelly clay loam. Clay content ranges from 15 to 30 percent. Rock fragments range from 35 to 70 percent gravel and 0 to 25 percent cobbles. Base saturation by sum of cations ranges from 65 to 75 percent. Organic matter ranges from 0.5 to 2 percent. Reaction ranges from moderately acid to slightly acid.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Sunnyslope soils are on ridge tops and side slopes on metamorphic Sierra Nevada foothills. Slopes range from 2 to 15 percent. These soils formed in residuum from metavolcanic rocks, mainly greenschist. Elevation is 200 to 1600 feet, (61 to 488 m). Mean annual precipitation is 24 to 32 inches, (610 to 813 mm). The mean annual temperature is 60 to 62 degrees F, (16 to 17 degrees C). Frost free season is 250 to 260 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dunstone, Loafercreek, and Sobrante soils. Dunstone soils are shallow to paralithic contact and have less than 35 percent rock fragments in the particle-size control section. Loafercreek and Sobrante are moderately deep to a paralithic contact.
DRAINAGE AND PERMEABILITY: Well drained; very high runoff; moderately rapid saturated hydraulic conductivity in the A horizon, moderate to moderately rapid in the Bt1 horizon and moderately rapid to moderately slow in the Bt2 and Bt3 horizons.
USE AND VEGETATION: This soil is used for livestock grazing, home site development and watershed. Vegetation is blue oak with or without interior liveoak, whiteleaf manzanita, foothill pine, buckbrush, wild oat, rattlesnake brome, hedgehog dogtail, soft chess, Italian rye grass, rose clover, dandelion and wild onion.
DISTRIBUTION AND EXTENT: Butte County, California and occurs in (M261Fb) Lower Foothills Metamorphic Belt Subsection of the (M261F) 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 Sunnyslope on the Loma Rica Quadrangle.
REMARKS: These soils were previously mapped as Rough broken and stony land (Rb) in the Soil Survey of Oroville Area, California 1926.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - zone from 0 to 2 inches, (0 to 5 cm) (A).
Argillic horizon - zone from 2 to 14 inches, (5 to 36 cm) (Bt).
Paralithic contact 14 inches (36 cm)
Particle-size control section - zone from 0 to 14 inches, (0 to 36 cm) (whole soil).
The soil moisture control section - zone from 8 to 14 inches, (20 to 36 cm).