LOCATION TOADTOWN CAEstablished Series
TAXONOMIC CLASS: Fine, parasesquic, mesic Andic Haplohumults
TYPICAL PEDON: Toadtown loam on an east southeast facing 7 percent slope under a cover of mixed conifers at an elevation of 3590 feet, (1094 m). When described on 11/28/95 the soil was dry throughout. (Colors are for dry soil unless otherwise noted)
Oi--0 to 2 inches, (0 to 5 cm); pine needles.
Oe--2 to 3 inches, (5 to 8 cm); partially decomposed forest litter, mostly pine needles.
A--3 to 5 inches, (8 to 13 cm); reddish brown (5YR 5/4) loam, reddish brown (5YR 4/3) moist; 26 percent clay; moderate medium subangular blocky structure parting to strong fine granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots and common fine roots; many very fine and fine tubular pores and many medium irregular pores and common coarse irregular pores; noneffervescent; 12 percent gravel; moderately acid, pH 5.7 by pH meter 1:1 water; NaF pH 10.5; clear smooth boundary. (2 to 4 inches, (5 to 10 cm) thick).
Bt1--5 to 8 inches, (13 to 20 cm); yellowish red (5YR 5/6) loam, reddish brown (5YR 4/4) moist; 27 percent clay; moderate medium subangular blocky structure parting to strong fine granular; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots and many medium roots; many very fine to medium irregular and tubular pores and common coarse irregular pores; many distinct discontinuous clay films on faces of peds and in pores; noneffervescent; 14 percent gravel; strongly acid, pH 5.5 by pH meter 1:1 water; NaF pH 10.3; clear smooth boundary.
Bt2--8 to 13 inches, (20 to 33 cm); yellowish red (5YR 5/6) clay loam, red (2.5YR 4/6) moist; 29 percent clay; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and coarse roots and many fine and medium roots; many very fine to coarse tubular pores; common distinct discontinuous clay films on faces of peds and in pores; noneffervescent; 10 percent gravel; strongly acid, pH 5.4 by pH meter 1:1 water; NaF pH 10.1; clear smooth boundary.
Bt3--13 to 18 inches, (33 to 46 cm); reddish yellow (5YR 6/6) clay, red (2.5YR 4/6) moist; 40 percent clay; strong medium subangular blocky structure; moderately hard, firm, slightly sticky and moderately plastic; common very fine roots and many fine, medium and coarse roots; many very fine to coarse tubular pores; many distinct discontinuous clay films on faces of peds and in pores; noneffervescent; 5 percent gravel; strongly acid, pH 5.3 by pH meter 1:1 water; NaF pH 9.6; clear smooth boundary.
Bt4--18 to 27 inches, (46 to 69 cm); reddish yellow (5YR 6/6) clay, red (2.5YR 5/6) moist; 43 percent clay; strong fine and medium subangular blocky structure; hard, very firm, slightly sticky and moderately plastic; common very fine and coarse roots and many fine and medium roots; many very fine and fine tubular pores; many distinct continuous clay films on faces of peds and in pores; noneffervescent; 2 percent gravel; strongly acid, pH 5.3 by pH meter 1:1 water; NaF pH 9.6; gradual smooth boundary.
Bt5--27 to 51 inches, (69 to 130 cm); reddish yellow (5YR 7/6) clay loam, reddish yellow (5YR 6/6) moist; 31 percent clay; strong medium angular blocky structure; moderately hard, firm, slightly sticky and moderately plastic; common very fine and fine roots; common very fine and fine tubular pores; many distinct continuous clay films on faces of peds and in pores and common prominent continuous clay films on faces of peds and in pores; noneffervescent; 1 percent gravel; strongly acid, pH 5.3 by pH meter 1:1 water; NaF pH 9.4; gradual irregular boundary.
Bt6--51 to 65 inches, (130 to 165 cm); reddish yellow (5YR 7/6) loam, yellowish red (5YR 5/8) moist; 27 percent clay; moderate medium angular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and fine tubular pores; many distinct discontinuous clay films on faces of peds and in pores and few prominent discontinuous clay films on faces of peds and in pores; noneffervescent; 2 percent gravel; strongly acid, pH 5.3 by pH meter 1:1 water; clear irregular boundary.
Bt7--65 to 75 inches, (165 to 190 cm); reddish yellow (5YR 7/6) loam, yellowish red (5YR 5/6) moist; 18 percent clay; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine and fine tubular pores; few prominent discontinuous clay films on faces of peds and in pores and many distinct discontinuous clay films on faces of peds and in pores; noneffervescent; 1 percent gravel; strongly acid, pH 5.2 by pH meter 1:1 water; clear wavy boundary. (Combined thickness of the Bt horizon is 56 to 78 inches, (142 to 198 cm) or more thick).
Crt--75 to 79 inches, (190 to 201 cm); reddish yellow (7.5YR 8/6) loam, yellowish red (5YR 5/6) moist; 17 percent clay; massive; slightly sticky and slightly plastic; few very fine and fine roots; common very fine and fine tubular pores; common prominent discontinuous clay films in pores; noneffervescent; 1 percent gravel; strongly acid, pH 5.2 by pH meter 1:1 water.
TYPE LOCATION: Butte County, California; about 1 mile southwest of Powellton, approximately 600 feet north and 1500 feet west of the southeast corner of Section 24, Township 24 N., Range 3 E., 39 degrees, 55 minutes, 00.7 seconds North latitude and 121 degrees, 34 minutes, 57.98 seconds West longitude, NAD27. U.S.G.S. Quad: Stirling City, California.
RANGE IN CHARACTERISTICS: Depth to paralithic bedrock is greater than 60 inches, (152 cm). The mean annual soil temperature is 54 to 57 degrees F, (12 to 14 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 35 to 45 percent clay and 2 to 5 percent rock fragments, mostly gravel. Mineralogy is parasesquic. Acid Oxalate extractable Al plus 1/2 Fe ranges from 1.1 to 1.57 to a depth of 13 inches, (33 cm). Rock fragments on the surface range from 0 to 35 percent gravel and 0 to 5 percent cobbles.
The A horizon dry color is 5YR 4/3, 4/4, 5/4, 5/6, 6/4, 2.5YR 4/6, 5/6, 7.5YR 5/4 or 6/6. Moist color is 5YR 3/3, 4/3, 4/4, 2.5YR 3/3, 3/4, 3/6, 4/4 or 7.5YR 3/3. Texture is loam, gravelly loam, sandy loam, gravelly sandy loam or very gravelly loam. Clay content ranges from 15 to 27 percent. Rock fragments range from 0 to 45 percent gravel. Organic matter ranges from 10 to 15 percent. Base saturation by sum of cations ranges from 15 to 25 percent. CEC by ammonium acetate ranges from 20 to 30. NaF pH ranges from 10 to 11. Reaction ranges from moderately acid to slightly acid.
The upper part of the Bt horizon dry color is 2.5YR 4/6, 5/6, 6/6, 5YR 4/4, 5/4, 5/6, 6/4 or 6/6. Moist color is 2.5YR 3/4, 3/6, 4/4, 4/6 or 5YR 4/4. Texture is loam, gravelly loam, clay loam, silty clay loam, sandy clay loam or gravelly clay loam. Clay content ranges from 23 to 37 percent. Rock fragments range from 0 to 20 percent gravel, and 0 to 10 percent cobbles. Organic matter ranges from 3 to 8 percent. Base saturation by sum of cations ranges from 10 to 20 percent. CEC by ammonium acetate ranges from 12 to 20. NaF pH ranges from 10 to 11. Reaction ranges from strongly acid to slightly acid.
The middle part of the Bt horizon dry color is 5YR 5/6, 5/8, 6/6, 7/6, 2.5YR 4/6, 5/6, 4/8, 5/8, 6/6, or 7/6. Moist color is 2.5YR 3/6, 4/4, 4/6, 4/8, 5/6, 6/8 or 5YR 5/8. Texture is silty clay, gravelly clay, clay, clay loam, or gravelly clay loam. Clay content ranges from 35 to 60 percent. Rock fragments range from 0 to 30 percent gravel and 0 to 10 percent cobbles. Organic matter ranges from 0.8 to 3 percent. Base saturation by sum of cations ranges from 10 to 20 percent. CEC by ammonium acetate ranges from 9 to 12. NaF pH ranges from 9 to 10. Reaction ranges from strongly acid to slightly acid.
The lower part of the Bt horizon dry color is 2.5YR 4/8, 5/6, 5/8, 5YR 5/6, 6/6, 6/8, 7/6 7.5YR 5/6, 6/6, 6/8 or 7/6. Moist color is 2.5YR 3/6, 4/6, 4/8, 5/6, 5YR 4/6, 5/6, 5/8, 6/6, 7.5YR 4/6, 5/6 or 5/8. Texture is clay loam, loam, silt loam, silty clay loam, cobbly silty clay loam, cobbly clay loam, gravelly clay loam or gravelly loam. Clay content ranges from 18 to 35 percent. Rock fragments range from 0 to 30 percent gravel and 0 to 20 percent cobbles. Organic matter ranges from 0.1 to 0.3 percent. Base saturation by sum of cations ranges from 2 to 10 percent. CEC by ammonium acetate ranges from 5 to 12. NaF pH ranges from 9 to 10. Reaction ranges from strongly acid to slightly acid.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Toadtown soils are on ridge tops and side slopes on metamorphic Sierra Nevada mountains. Slopes range from 2 to 70 percent. These soils formed in residuum and colluvium weathered from metadiorite, metavolcanic rocks, gabbro and diorite. Elevation is 2200 to 4375 feet, (671 to 1334 m). Mean annual precipitation is 60 to 75 inches, (1524 to 1905 mm). The mean annual soil temperature is 52 to 55 degrees F, (11 to 13 degrees C). Frost free season is 140 to 190 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Powellton and Dixmine and Hietanen soils. Powellton soils are on ridge tops and side slopes and are fine-loamy. Dixmine soils are on ridge tops and side slopes, are clayey-skeletal and deep. Hietanen soils are on ridge tops and side slopes, are fine-loamy and deep.
DRAINAGE AND PERMEABILITY: Well drained; medium to high runoff; moderate to moderately rapid saturated hydraulic conductivity in the A horizon, moderate to slow in the Bt horizon.
USE AND VEGETATION: This soil is used for timber production, wildlife habitat and watershed. Vegetation is ponderosa pine, tanoak, sugar pine, Douglas-fir, incense cedar, white fir, whitevein shinleaf, Pacific dogwood, California black oak and broadleaf starflower.
DISTRIBUTION AND EXTENT: Butte County, California. 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 Toadtown on the Stirling City Quad.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - zone from 3 to 5 inches, (8 to 13 cm) (A).
Argillic horizon - zone from 13 to 27 inches, (33 to 69 cm) (Bt3, Bt4).
Particle-size control section - zone from 13 to 27 inches, (33 to 69 cm).
Soil moisture control section - zone from 9 to 21 inches, (23 to 53 cm).
Bulk density is assumed to be 1 g/cc or less in the upper 10 inches, (25 cm).
ADDITIONAL DATA: Reference samples from lab pedon numbers: 96P0139, 96P0130 and 96P0131, NSSL, Lincoln, NE.