LOCATION FEATHERFALLS CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Ultic Palexeralfs
TYPICAL PEDON: Featherfalls sandy loam, on a northwest facing 28 percent slope under a cover of conifers, hardwoods and shrubs at an elevation of 2840 feet, (866 m). When described on 7/14/1998 the soil was dry throughout. (Colors are for dry soil unless otherwise noted).
Oi--0 to 1 inches, (0 to 3 cm); slightly decomposed leaves, needles, and twig litter; abrupt smooth boundary.
A1--1 to 4 inches, (3 to 10 cm); pale brown (10YR 6/3) sandy loam, brown (7.5YR 4/3) moist; 14 percent clay; moderate fine subangular blocky structure; slightly hard, firm, slightly sticky, slightly plastic; many very fine roots; many very fine irregular pores; 10 percent subangular gravel; slightly acid, pH 6.5 by Hellige-Truog; NaF pH 9.0; abrupt smooth boundary.
A2--4 to 7 inches, (10 to 18 cm); very pale brown (10YR 7/4) sandy loam, brown (7.5YR 5/4) moist; 18 percent clay; moderate fine subangular blocky structure; slightly hard, firm, slightly sticky, moderately plastic; common fine and medium roots; many very fine irregular pores; 2 percent mica flakes; 10 percent subrounded gravel; slightly acid, pH 6.5 by Hellige-Truog; NaF pH 9.8; clear smooth boundary. (Combined thickness of the A horizon is 6 to 22 inches, (15 to 56 cm) thick).
Bt1--7 to 17 inches, (18 to 43 cm); light brown (7.5YR 6/4) sandy clay loam, strong brown (7.5YR 4/6) moist; 24 percent clay; moderate medium subangular blocky structure; hard, firm, moderately sticky, moderately plastic; common fine and medium roots and few coarse roots; common very fine tubular pores; 5 percent discontinuous prominent clay films on faces of peds and in pores; 10 percent mica flakes; 10 percent subrounded gravel; slightly acid, pH 6.5 by Hellige-Truog; NaF pH 9.8; gradual smooth boundary.
Bt2--17 to 24 inches, (43 to 61 cm); reddish yellow (7.5YR 7/6) sandy clay loam, yellowish red (5YR 4/6) moist; 29 percent clay; moderate medium subangular blocky structure; hard, firm, moderately sticky, moderately plastic; few medium and coarse roots; common very fine tubular pores; 60 percent discontinuous prominent clay films on faces of peds and in pores; 10 percent fine irregular black (N 2/0) iron-manganese masses; 20 percent mica flakes; 5 percent subrounded gravel; moderately acid, pH 6.0 by Hellige-Truog; NaF pH 10.0; gradual smooth boundary.
Bt3--24 to 32 inches, (61 to 81 cm); reddish yellow (7.5YR 7/6) sandy clay loam, yellowish red (5YR 5/6) moist; 30 percent clay; moderate medium subangular blocky structure; hard, firm, moderately sticky, moderately plastic; few fine and medium roots; common very fine tubular pores; 60 percent discontinuous prominent clay films on faces of peds and in pores; 25 percent mica flakes; 5 percent subrounded gravel; moderately acid, pH 6.0 by Hellige-Truog; gradual smooth boundary.
Bt4--32 to 42 inches, (81 to 107 cm); reddish yellow (7.5YR 7/6) sandy clay loam, strong brown (7.5YR 4/6) moist; 33 percent clay; moderate medium subangular blocky structure; hard, firm, moderately sticky, moderately plastic; few fine and medium roots; common very fine tubular pores; 50 percent discontinuous prominent clay films on faces of peds and in pores; 25 percent mica flakes; moderately acid, pH 6.0 by Hellige-Truog; gradual smooth boundary. (Combined thickness of the Bt horizon is 28 to 53 inches, (71 to 135 cm) thick)
BCt1--42 to 61 inches, (107 to 155 cm); reddish yellow (7.5YR 7/6) paracobbly sandy clay loam, strong brown (7.5YR 4/6) moist; 34 percent clay; moderate medium subangular blocky structure; hard, very firm, moderately sticky, moderately plastic; few fine and medium roots; few very fine tubular pores; 80 percent continuous prominent clay films on faces of peds and in pores; 25 percent mica flakes; 33 percent paracobbles moderately acid, pH 6.0 by Hellige-Truog; gradual smooth boundary.
BCt2--61 to 72 inches, (155 to 183 cm); reddish yellow (7.5YR 7/6) paracobbly sandy clay loam, strong brown (7.5YR 4/6) moist; 33 percent clay; weak medium subangular blocky structure; hard, very firm, moderately sticky, moderately plastic; few fine and medium roots; few very fine tubular pores; 60 percent continuous prominent clay films on faces of peds and in pores; 10 percent mica flakes; 33 percent paracobbles slightly acid, pH 6.5 by Hellige-Truog; gradual smooth boundary. (Combined thickness of the BCt horizon is 0 to 30 inches, (0 to 76 cm) thick).
Crt--72 to 80 inches, (183 to 203 cm); pink (7.5YR 8/4) very paragravelly sandy clay loam, brown (7.5YR 5/4) moist; 25 percent clay; massive parting to weak medium subangular blocky structure; hard, very firm, slightly sticky, slightly plastic; few fine and medium roots; few very fine tubular pores; 50 percent discontinuous prominent clay films on faces of peds and in pores; 10 percent mica flakes; 45 percent paragravel moderately acid, pH 6.0 by Hellige-Truog; rock structure is evident, slakes in water.
TYPE LOCATION: Butte County, California, about 0.8 miles north of Feather Falls, approximately 750 feet east and 200 feet north of the southeast corner of Section 12, Township 20 N., Range 6 E., 39 degrees, 36 minutes, 22 seconds North latitude and 121 degrees, 15 minutes, 26 seconds West longitude, NAD83 - U.S.G.S. Quad: Forbestown, California.
RANGE IN CHARACTERISTICS: Depth to paralithic bedrock is greater than 60 inches, (152cm). The mean annual soil temperature is 53 to 59 degrees F, (12 to 15 degrees C). The particle-size control section averages 20 to 27 percent clay and 0 to 25 percent rock fragments, mostly gravel. Mineralogy is mixed. NaF pH ranges from less than 9.0 to 10.0 throughout. Rock fragments on the surface range from 0 to 10 percent gravel and 0 to 25 percent boulders.
The A horizon dry color is 10YR 5/3, 5/4, 6/3, 6/4, 7/2, 7/3, 7/4, 8/3 or 7.5YR 6/4. Moist color is 10YR 3/2, 3/3, 4/2, 4/3, 4/4, 5/2, 5/4, 6/4, 7.5YR 3/3, 4/2, 4/3, 4/4 or 5/4. Texture is sandy loam, coarse sandy loam, loam, sandy clay loam or gravelly coarse sandy loam. Clay content ranges from 8 to 23 percent. Organic matter ranges from 1 to 4 percent. Rock fragments range from 0 to 30 percent gravel. Reaction ranges from strongly acid to slightly acid.
The Bt horizon dry color is 10YR 7/3, 7/4, 7/6, 8/3, 8/4, 7.5YR 6/4, 6/6, 7/6, 5YR 5/4, 5/6 or 6/6. Moist color is 10YR 5/3, 5/4, 5/6, 6/6, 7/4, 7.5YR 4/3, 4/4, 4/6, 5/6, 6/6, 5/8, 5YR 4/4, 4/6, 5/6, 5/8, 2.5YR 4/6, 5/6 or 5/8. Texture is sandy clay loam, clay loam, loam, sandy loam or gravelly sandy clay loam. Clay content ranges from 16 to 33 percent. Organic matter ranges from 0.1 to 1.5 percent. Rock fragments range from 0 to 30 percent gravel. Reaction ranges from strongly acid to neutral.
The BCt horizon dry color is 10YR 8/4, 7.5YR 5/4, 6/6, 7/6 or 8/2. Moist color is 10YR 7/6, 7.5YR 4/6, 7/6, 5YR 4/4 or 5/6. Texture is sandy clay loam, sandy clay or paracobbly sandy clay loam. Clay content ranges from 25 to 38 percent. Organic matter ranges from 0 to 0.2 percent. Rock fragments range from 0 to 10 percent gravel and 5 to 35 percent paracobbles. Reaction ranges from moderately acid to slightly acid.
The Crt horizon dry color is 7.5YR 8/4 or 10YR 8/4. Moist color is 7.5YR 5/4 or 10YR 7/6. Texture is sandy clay loam, sandy loam, very paragravelly sandy clay loam, extremely paragravelly loamy coarse sand or loamy coarse sand. Clay content ranges from 2 to 27 percent. Rock fragments range from 0 to 70 percent paragravel. Reaction ranges from very strongly acid to moderately acid.
COMPETING SERIES: These are the Jafa and Weaverville soils. Jafa soils have 25 to 35 percent clay in the particle-size control section, are formed in alluvium weathered from dominantly sedimentary rocks and are on alluvial fans and terraces. Weaverville soils have 27 to 35 percent clay in the particle-size control section and the soil moisture control section is dry for 120 days.
GEOGRAPHIC SETTING: Featherfalls soils are on ridge tops and side slopes on granitic Sierra Nevada mountains. Slopes range from 2 to 70 percent. These soils formed in residuum and colluvium weathered from coarse-grained intrusive igneous rocks such as quartz diorite and trondhjemite. Elevation is 2000 to 3000 feet, (610 to 914 m). Mean annual precipitation is 55 to 60 inches, (1397 to 1524 mm). The mean annual temperature is 54 to 56 degrees F, (12 to 13 degrees C). Frost free season is 180 to 230 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Craigsaddle, Crystalhill, Chawanakee, Islandbar, Jocal, Oregongulch, Powellton, Sites and Toadtown soils. Craigsaddle soils are deep to densic bedrock, fine-loamy and thermic. Crystalhill soils are very deep to densic bedrock, are coarse-loamy and thermic. Chawanakee soils are shallow and loamy. Islandbar soils are very deep to paralithic bedrock and are coarse-loamy. Jocal soils are very deep, fine-loamy and have base saturation less than 35 percent. Powellton soils are very deep, fine-loamy, have parasesquic mineralogy and have base saturation less than 35 percent. Sites soils are very deep, fine and have base saturation less than 35 percent. Toadtown soils are very deep, fine, have parasesquic mineralogy and have base saturation less than 35 percent.
DRAINAGE AND PERMEABILITY: Well drained; low to medium runoff; moderate to moderately rapid saturated hydraulic conductivity in the A horizon, moderately slow to moderately rapid in the Bt horizon and moderately slow to moderate in the BCt horizon.
USE AND VEGETATION: This soil is used for timber production, home site development, wildlife habitat and watershed. Vegetation is ponderosa pine, Douglas-fir, incense cedar, Pacific madrone, California black oak, tanoak, some canyon live oak and California laurel with a dense understory of whiteleaf manzanita, deerbrush, Pacific poison oak, honeysuckle, dogwood, toyon, Sierra iris, brackenfern, broadleaf starflower and Sierra gooseberry.
DISTRIBUTION AND EXTENT: Butte County, California and occur in (M261Ef) Granitic and Metamorphic Hills subsection of the (M261F) Sierra Nevada Mountains section. MLRA 22A - Sierra Nevada Range. The soils are inextensive and occur on the Bald Rock and Concow plutons.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Butte County, California 2005. Source of name from the town of Featherfalls.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - zone from 1 to 7 inches, (3 to 18 cm) (A1, A2)
Argillic horizon - zone from 7 to 72 inches, (18 to 182 cm) (Bt1, Bt2, Bt3, Bt4, BCt1, BCt2)
Particle-size control section for this pedon: 7.0 to 26 inches, (18 to 67 cm)
The soil moisture control section - zone from 9 to 23 inches, (23 to 58 cm) is dry in all parts from about June to mid October (about 135 days).
Base saturation by sum of cations is assumed to be 35 to 50 percent.