LOCATION TIMBERISLAND CAEstablished Series
TAXONOMIC CLASS: Medial-skeletal, ferrihydritic, mesic Humic Haploxerands
TYPICAL PEDON: Timberisland very gravelly medial sandy loam, on a southwest facing 30 percent slope under a cover of mixed conifers at an elevation of 4325 feet, (1318 m). When described on 6/20/95 the soil was moist throughout. (Colors are for dry soil unless otherwise noted)
Oi--0 to 1.5 inches, (0 to 3 cm); fresh needles, leaves, cones, and twigs.
Oe--1.5 to 3 inches, (3 to 8 cm); moderately decomposed needles, leaves, cones and twig litter.
A1--3 to 6 inches, (8 to 15 cm); brown (10YR 5/3) very gravelly medial sandy loam, very dark brown (10YR 2/2) moist; 16 percent clay; weak fine subangular blocky structure parting to single grain; loose, very friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine irregular pores; 40 percent subangular basalt gravel; strongly acid, pH 5.5 by Hellige-Truog; NaF pH 9.0; abrupt smooth boundary. (2 to 3 inches, (5 to 8 cm) thick)
A2--6 to 14 inches, (15 to 36 cm); brown (10YR 5/3) very gravelly medial sandy loam, very dark brown (10YR 2/2) moist; 16 percent clay; weak fine subangular blocky structure parting to single grain; loose, very friable, slightly sticky and slightly plastic; many fine, common very fine, and few medium roots; many very fine irregular pores; 40 percent subangular basalt gravel, 5 percent subangular basalt cobbles; strongly acid, pH 5.5 by Hellige-Truog; NaF pH 11.2; abrupt smooth boundary. (3 to 8 inches, (8 to 20 cm) thick)
Bw1--14 to 25 inches, (36 to 64 cm); brown (10YR 5/3) very gravelly medial sandy loam, very dark grayish brown (10YR 3/2) moist; 18 percent clay; weak fine subangular blocky structure; loose, very friable, slightly sticky and slightly plastic; many fine, common very fine, and few medium roots; many very fine irregular pores; 5 percent clay films on rock fragments and on faces of peds and in pores; 40 percent subangular basalt gravel, 10 percent subangular basalt cobbles; strongly acid, pH 5.5 by Hellige-Truog; NaF pH 11.2; clear smooth boundary.
Bw2--25 to 35 inches, (64 to 89 cm); yellowish brown (10YR 5/4) extremely cobbly medial sandy loam, dark brown (10YR 3/3) moist; 12 percent clay; weak fine subangular blocky structure; loose, very friable, nonsticky and slightly plastic; common fine and medium roots; many very fine irregular pores; 35 percent subangular basalt gravel and 35 percent subangular basalt cobbles; moderately acid, pH 5.8 by Hellige-Truog; NaF pH 11.1; gradual wavy boundary.
Bw3--35 to 48 inches, (89 to 122 cm); yellowish brown (10YR 5/4) extremely cobbly medial sandy loam, dark brown (10YR 3/3) moist; 12 percent clay; weak fine subangular blocky structure; slightly hard, very friable, nonsticky and slightly plastic; common fine roots; many very fine irregular pores; 10 percent subangular basalt gravel and 80 percent subangular basalt cobbles; moderately acid, pH 5.8 by Hellige-Truog; NaF pH 10.3; abrupt smooth boundary. (Combined thickness of the Bw horizon is 23 to 38 inches, (58 to 97 cm) thick).
R--48 inches, (122 cm); indurated basalt; very few roots in fractures greater than 12 inches, (31 cm) apart.
TYPE LOCATION: Butte County, California; about 2.2 miles northeast of Camp Eighteen, approximately 600 feet west and 1450 feet north of the southeast corner of Section 25, Township 21 N., Range 7 E., 39 degrees, 38 minutes, 48 seconds North latitude and 121 degrees, 8 minutes, 16 seconds West longitude, NAD27. U.S.G.S. Quad: Cascade, California.
RANGE IN CHARACTERISTICS: Depth to lithic bedrock is 40 to 60 inches, (102 to 152 cm). The mean annual soil temperature is 47 to 54 degrees F, (8 to 12 degrees C). The soil moisture control section is dry in all parts from about July to about October (about 90 days). The particle-size control section averages 10 to 18 percent clay and 40 to 60 percent rock fragments, mostly gravel and cobbles. Mineralogy is ferrihydridic. Rock fragments on the surface range from 5 to 40 percent gravel, 0 to 25 percent cobbles, 0 to 15 percent stones and 0 to 5 percent boulders.
The A1 horizon dry color is 10YR 3/2, 4/2, 4/3 or 5/3. Moist color is 10YR 2/1, 2/2, 3/1, 3/2, 7.5YR 2/0 or 3/2. Texture is very gravelly medial sandy loam, gravelly medial sandy loam, medial sandy loam or gravelly medial coarse sandy loam. Clay content ranges from 5 to 18 percent. Rock fragments range from 5 to 40 percent gravel, 0 to 10 percent cobbles, and 0 to 10 percent stones. Organic matter ranges from 15 to 52 percent. Base saturation by ammonium acetate ranges from 20 to 40 percent. Acid oxalate extractable Al plus 1/2 Fe ranges from 2.0 to 2.5. P retention ranges from 80 to 85. Glass ranges from 2 to 5 percent. NaF pH ranges from 9.0 to 10.0. Reaction ranges from strongly acid to slightly acid.
The A2 horizon dry color is 10YR 3/2, 4/2, 4/3 or 5/3. Moist color is 10YR 2/1, 2/2, 3/1, 3/2, 7.5YR 2/0 or 3/2. Texture is medial sandy loam, gravelly medial sandy loam, very gravelly medial sandy loam, or gravelly medial coarse sandy loam. Clay content ranges from 5 to 18 percent. Rock fragments range from 5 to 40 percent gravel, 0 to 10 percent cobbles and 0 to 10 percent stones. Organic matter ranges from 10 to 20 percent. Base saturation by ammonium acetate ranges from 5 to 10 percent. Acid oxalate extractable Al plus 1/2 Fe ranges from 2.0 to 3.5. P retention ranges from 85 to 95. Glass ranges from 2 to 5 percent. NaF pH ranges from 10.0 to 11.5. Reaction ranges from strongly acid to slightly acid.
The Bw1 horizon dry color is 10YR 4/2, 5/2, 5/3 or 7.5YR 4/3. Moist color is 10YR 2/1, 3/2, 3/3 or 7.5YR 4/3. Texture is gravelly medial sandy loam, very gravelly medial sandy loam or extremely gravelly medial sandy loam. Clay content ranges from 8 to 18 percent. Rock fragments range from 30 to 40 percent gravel, 0 to 20 percent cobbles, 0 to 10 percent stones and 0 to 5 percent boulders. Organic matter ranges from 10 to 18 percent. Base saturation by ammonium acetate ranges from 2 to 5 percent. Acid oxalate extractable Al plus 1/2 Fe ranges from 2.0 to 3.5. P retention ranges from 85 to 95. Glass ranges from 1 to 5 percent. NaF pH ranges from 11 to 11.5. Reaction ranges from strongly acid to slightly acid.
The Bw2 and Bw3 horizon dry color is 10YR 4/2, 5/2, 5/3, 5/4, 7.5YR 4/2, 4/3, 4/4, 5/3 or 2.5Y 5/4. Moist color is 10YR 3/2, 3/3, 7.5YR 3/2, 3/3, 3/4/ 4/3 or 2.5Y 3/2. Texture is extremely cobbly medial fine sandy loam, extremely cobbly medial sandy loam, extremely gravelly medial sandy loam, or very cobbly medial sandy loam. Clay content ranges from 10 to 22 percent. Rock fragments range from 10 to 60 percent gravel, 25 to 80 percent cobbles, 0 to 5 percent stones and 0 to 5 percent boulders. Organic matter ranges from 2 to 10 percent. Base saturation by ammonium acetate ranges from 2 to 5 percent. Acid oxalate extractable Al plus 1/2 Fe ranges from 2.0 to 3.5. P retention ranges from 85 to 96. Glass ranges from 1 to 5 percent. NaF pH ranges from 10.0 to 11.5. Reaction ranges from very strongly acid to slightly acid.
COMPETING SERIES: This is the Shakeridge series. Shakeridge soils are very deep to lithic contact of basalt.
GEOGRAPHIC SETTING: Timberisland soils are on basalt benches, ridge tops and side slopes on ridges on volcanic Sierra Nevada mountains. Slopes range from 0 to 30 percent. These soils formed in mixed tephra and colluvium and residuum from Lovejoy basalt. Elevation is 3200 to 4800 feet, (975 to 1463 m). Mean annual precipitation is 75 to 80 inches, (1905 to 2032 mm). The mean annual soil 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, Mudwash and Shakeridge soils. Lavatop soils are moderately deep to lithic contact of basalt. Lumpkin soils are shallow to lithic contact of basalt. Powderhouse soils are moderately deep to a paralithic contact of mudflow. McNair soils are deep to a paralithic contact of mudflow. Mudwash soils are very deep to a paralithic contact, medial over loamy, and are in depressional areas between lava flows. Shakeridge are very deep to a lithic contact of 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, watershed and wildlife habitat. Vegetation is incense cedar, ponderosa pine, white fir, sugar pine, Pacific madrone, tanoak, Douglas-fir and California black oak with an understory of whitethorn ceanothus, greenleaf manzanita, western service berry, scrub oak, deerbrush, huckleberry oak, lupine, brackenfern, common snowberry and Sierra gooseberry.
DISTRIBUTION AND EXTENT: Butte and Plumas Counties, California and occurs in 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: Butte County, California 2005. Source of name from Timber Island, on the Cascade quad.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Umbric epipedon - zone from 3 to 48 inches, (8 to 122 cm) (A1, A2, Bw1, Bw2, Bw3).
Lithic contact - the zone at 48 inches, (122 cm) (R).
Particle-size control section - zone from 3 to 40 inches, (8 to 102 cm).
Soil moisture control section - zone from 14 to 42 inches, (33 to 107 cm).
Andic soil properties the zone from 3 to 48 inches, (8 to 122 cm). (data assumed from nearby pedon)
ADDITIONAL DATA: Reference samples from nearby profile S98CA-007-004 NSSL, Lincoln, NE.