LOCATION SHAKERIDGE CAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, ferrihydritic, mesic Humic Haploxerands
TYPICAL PEDON: Shakeridge gravelly medial coarse sandy loam on a northwest facing 48 percent slope under a cover of mixed conifers at an elevation of 4580 feet, (1396 m). When described on 12/17/96 the soil was moist throughout. (Colors are for dry soil unless otherwise stated)
Oi--0 to 2 inches, (0 to 5 cm); fresh and slightly decomposed needles, leaves, and twig litter.
A1--2 to 4 inches, (5 to 10 cm); dark brown (10YR 3/3) gravelly medial coarse sandy loam, black (10YR 2/1) moist; 9 percent clay; weak very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine roots; common very fine irregular pores and common very fine vesicular pores; 30 percent subangular basalt gravel; slightly acid, pH 6.3 by pH meter 1.1 water; NaF pH 10.4; abrupt smooth boundary.
A2--4 to 7 inches, (10 to 18 cm); dark brown (10YR 3/3) extremely gravelly medial coarse sandy loam, very dark brown (10YR 2/2) moist; 9 percent clay; weak very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; common irregular pores; 65 percent subangular basalt gravel; slightly acid, pH 6.4 by pH meter 1:1 water; NaF pH 10.5; abrupt smooth boundary. (Combined thickness of the A horizon is 10 to 19 inches, (25 to 48 cm) thick.)
Bw1--7 to 19 inches, (18 to 48 cm); brown (10YR 4/3) extremely gravelly medial coarse sandy loam, dark brown (7.5YR 3/3) moist; 16 percent clay; weak very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots and few medium roots; common irregular pores; 70 percent angular basalt gravel; slightly acid, pH 6.3 by pH meter 1:1 water; NaF pH 10.3; clear smooth boundary.
Bw2--19 to 25 inches, (48 to 64 cm); brown (10YR 4/3) extremely gravelly medial coarse sandy loam, dark brown (7.5YR 3/2) moist; 16 percent clay; weak very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine and medium roots and few coarse roots; common irregular pores; 70 percent angular basalt gravel and 5 percent angular basalt cobbles; slightly acid, pH 6.5 by pH meter 1:1 water; NaF pH 10.3; gradual smooth boundary.
Bw3--25 to 36 inches, (64 to 91 cm); brown (10YR 5/3) extremely gravelly medial coarse sandy loam, dark brown (7.5YR 3/2) moist; 18 percent clay; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine roots and common fine to coarse roots; common irregular pores; 70 percent subangular basalt gravel and 5 percent subangular basalt cobbles; slightly acid, pH 6.1 by pH meter 1:1 water; NaF pH 10.3; gradual smooth boundary.
Bw4--36 to 55 inches, (91 to 140 cm); brown (10YR 5/3) very gravelly medial coarse sandy loam, dark brown (7.5YR 3/2) moist; 18 percent clay; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine to coarse roots; common irregular pores; 50 percent subangular basalt gravel and 5 percent subangular basalt cobbles; moderately acid, pH 6.0 by pH meter 1:1 water; NaF pH 10.4; gradual smooth boundary.
Bw5--55 to 71 inches, (140 to 180 cm); brown (10YR 5/3) extremely gravelly medial coarse sandy loam, dark brown (7.5YR 3/2) moist; 18 percent clay; moderate fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine to coarse roots; common irregular pores; 55 percent subangular basalt gravel and 5 percent subangular basalt cobbles; NaF pH 10.5; slightly acid, pH 6.1 by pH meter 1:1 water; clear smooth boundary.
Bw6--71 to 87 inches, (180 to 221 cm); brown (10YR 5/3) extremely gravelly coarse sandy loam, dark brown (7.5YR 3/2) moist; 18 percent clay; weak very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine and medium roots; common irregular pores; 60 percent subangular basalt gravel and 5 percent subangular basalt cobbles; moderately acid, pH 5.9 by pH meter 1:1 water. 10.5 NaF pH. (Combined thickness of the Bw horizon is 53 to 80 inches, (135 to 203 cm) or more thick.)
TYPE LOCATION: Plumas County, California; about 2.3 miles southeast of Cascade, approximately 1250 feet north and 1200 feet east of the southwest corner of Section 13, Township 21 N., Range 7 E., 39 degrees, 40 minutes, 29.7 seconds North latitude and 121 degrees, 8 minutes, 57.5 seconds West longitude, NAD83. - U.S.G.S. Quad: Cascade, California.
RANGE IN CHARACTERISTICS: Depth to lithic bedrock is greater than 60 inches, (152 cm). The mean annual soil temperature is 47 to 54 degrees F, (11 to 12 degrees C). The soil moisture control section is dry in all parts from about July to about September (about 90 days). The particle-size control section averages 12 to 18 percent clay and 40 to 60 percent rock fragments, mostly gravel and cobbles. Rock fragments on the surface range from 10 to 20 percent gravel, 0 to 10 percent cobbles and 0 to 5 percent stones. Mineralogy is ferrihydritic. Base saturation by ammonium acetate is greater than 50 percent throughout. Acid Oxalate extractable Al plus 1/2 Fe ranges from 2.1 to 3.3 to a depth of 71 inches, (180 cm). Some pedons have paralithic contacts of volcaniclastic material, tuff or mudflow breccia below a depth of 60 inches, (152 cm).
The A horizon dry color is 10YR 3/2 or 3/3. Moist color is 10YR 2/1, 2/2 or 7.5YR 2.5/2. Texture is gravelly medial coarse sandy loam, very gravelly medial sandy loam or extremely gravelly medial sandy loam. Organic matter ranges from 5 to 12 percent. Clay content ranges from 5 to 12 percent. Rock fragments range from 20 to 65 percent gravel and 5 to 20 percent cobbles. NaF pH ranges from 10.4 to 11.5. Reaction ranges from moderately acid to slightly acid.
The Bw horizon dry color is 10YR 4/3 or 5/3. Moist color is 10YR 3/2, 7.5YR 3/2, 3/3 or 4/4. Texture is extremely gravelly medial sandy loam, very gravelly medial sandy loam, very gravelly medial coarse sandy loam, extremely gravelly medial coarse sandy loam, extremely cobbly medial sandy loam, extremely stony medial sandy loam or extremely gravelly coarse sandy loam. Organic matter ranges from 1 to 3 percent. Clay content ranges from 5 to 18 percent. Rock fragments range from 10 to 70 percent gravel, 0 to 50 percent cobbles and 0 to 70 percent stones. NaF pH ranges from 10.3 to 11.0. Reaction ranges from very strongly acid to slightly acid.
COMPETING SERIES: This is the Timberisland series. Timberisland soils are deep to lithic basalt.
GEOGRAPHIC SETTING: Shakeridge soils are on backslopes and side slopes on basalt ridges on volcanic Sierra Nevada mountains. Slopes range from 0 to 70 percent. These soils formed in mixed tephra and colluvium and residuum weathered from Lovejoy basalt. Elevation is 3600 to 4800 feet, (1097 to 1463 m). Mean annual precipitation is 75 to 80 inches, (1905 to 2032 mm). The mean annual temperature is 50 to 52 degrees F, (10 to 11 degrees C). Frost free season is 110 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lavatop, Lumpkin, Powderhouse, McNair and Timberisland soils. Lavatop soils are moderately deep to lithic basalt. Lumpkin soils are on narrow lava plateaus and are shallow to lithic basalt. Powderhouse soils are moderately deep to paralithic mudflow breccia. McNair soils are deep to paralithic pyroclastic mudflow breccia. Timberisland soils are deep to lithic basalt.
DRAINAGE AND PERMEABILITY: Well drained; low to medium runoff; moderately rapid saturated hydraulic conductivity.
USE AND VEGETATION: This soil is used for timber production, wildlife habitat and watershed. Vegetation is white fir, sugar pine, incense cedar, and California black oak, with an understory of bigleaf maple, California hazel, dogwood, Sierra gooseberry, and whitevein shinleaf, and some ponderosa pine and Douglas-fir.
DISTRIBUTION AND EXTENT: Butte and Plumas counties, California and occurs on the Upper Batholith and Volcanic Flows subsection of the Sierra Nevada section. MLRA 22A Sierra Nevada Range. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Plumas County, California 2005. Source of name from Shake Ridge.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - zone from 2 to 19 inches, (5 to 48 cm) (A1, A2, Bw1)
Cambic horizon - zone from 19 to 87 inches, (48 to 221 cm) (Bw2, Bw3, Bw4, Bw5, Bw6).
Andic Soil Properties - zone from 2 to 71 inches, (5 to 180 cm) (A1, A2, Bw1, Bw2, Bw3, Bw4, Bw5)
Bulk density assumed to be less than 1.0 g/cc to a depth of 71 inches, (180 cm).
Particle-size control section - zone from 2 to 40 inches, (5 to 102 cm).
Soil moisture control section - zone from 20 to 61 inches, (51 to 155 cm).
Ferrihydritic mineralogy: 8(Si) plus 2(Fe) is greater than 5, Fe is greater than Si. (3.94 vs 3.28)
Percent clay in horizon description is by field estimate.
ADDITIONAL DATA: Reference samples from lab pedon number: 97P0310, NSSL, Lincoln, NE