LOCATION UPDEGRAFF CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Ultic Argixerolls
TYPICAL PEDON: Updegraff loam - on a west-facing convex slope of 25 percent under Oregon white oak, Douglas-fir and ponderosa pine at 2,250 feet elevation. (Colors are for dry soil unless otherwise stated. When described July 1, 1981, the soil was dry to 20 inches and moist below.)
0i--1 inch to 0; decomposed leaves and twigs.
A1--0 to 7 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; slightly hard, friable, nonsticky and nonplastic; many very fine and common fine roots; many very fine, common fine and few medium tubular pores; 5 percent 2 to 20 mm pebbles; neutral (pH 7.0); gradual wavy boundary.
A2--7 to 12 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; slightly hard, firm, slightly sticky and slightly plastic; common very fine and few fine, medium and coarse roots; many very fine and fine tubular and few very fine interstitial pores; neutral (pH 6.8); clear wavy boundary. (Combined thickness of A horizon ranges from 10 to 18 inches)
Bt1--12 to 16 inches; light yellowish brown (10YR 6/4) clay loam, dark brown (10YR 3/3) moist; strong coarse and very coarse subangular blocky structure parting to strong medium subangular blocky; slightly hard, friable, slightly sticky and plastic; common fine and few very fine, medium and coarse roots; few very fine, fine and coarse tubular pores; common thin clay films in pores and on peds; slightly acid (pH 6.5); gradual wavy boundary.
Bt2--16 to 22 inches; yellowish brown (10YR 5/4) clay loam, dark yellowish brown (10YR 4/4) moist; strong coarse and very coarse subangular blocky structure parting to strong medium subangular blocky; hard, firm, slightly sticky and plastic; few very fine and fine roots; few very fine and fine tubular and few fine interstitial pores; many moderately thick clay films on peds and in pores; 5 percent 2 to 15 mm pebbles and 5 percent 75 to 150 mm cobbles; slightly acid (pH 6.5); gradual wavy boundary.
Bt3--22 to 36 inches; grayish brown (10YR 5/2) clay loam, dark grayish brown (10YR 4/2) moist; moderate medium subangular blocky structure; very hard, very firm, slightly sticky and plastic; few fine roots; few fine tubular pores; many moderately thick clay films in pores and on peds; 10 percent 2 to 10 mm pebbles; moderately acid (pH 6.0); gradual wavy boundary. (Combined thickness of the Bt horizon ranges from 22 to 50 inches)
Bt4--36 to 45 inches; grayish brown (10YR 5/2) clay loam, grayish brown (10YR 5/2) moist; moderate medium subangular blocky structure; very hard, very firm, slightly sticky and plastic; few fine and medium roots; few very fine and fine tubular pores; many moderately thick clay films in pores and on peds; 5 percent 2 to 30 mm soft rock fragments; neutral (pH 6.8).
R--45 inches; fractured schist and graywacke.
TYPE LOCATION: Mendocino County, California; near Willits, approximately 1.5 miles due south of Finney Lake, 0.6 mile east from Finney Lake Camp headquarters along main dirt road, 0.6 mile south to intersection, 0.7 mile southwest to jeep trail and 0.4 mile northeast along jeep trail crossing small intermittent creek; 1,000 feet south and 250 feet west of the northwest corner of section 22, T.18 N., R.13 W., M.D.B.M.
RANGE IN CHARACTERISTICS: Depth to rock is 40 to 60 inches. The soil between a depth of 6 to 18 inches is dry in all parts from July through October and is moist in all parts from December through May. The mean annual soil temperature varies from 49 to 59 degrees F. The base saturation by sum of cations is 50 to 90 percent throughout the profile and is less than 75 percent in some part of the upper 30 inches. A stone line occurs in most pedons between a depth of 10 to 24 inches. It contains 5 to 30 percent 2 to 75 mm gravel and 5 to 10 percent 75 to 150 mm cobbles. The mollic epipedon is 10 to 18 inches thick and has 1 to 5 percent organic matter. The soil is moderately acid to neutral throughout. The particle-size control section averages 30 to 35 percent clay and 5 to 30 percent rock fragments.
The A horizon is 10YR 4/2, 4/3, 5/2 or 5/3. Moist colors are 10YR 2/2, 3/2 or 3/3. It is loam in the upper part and may be gravelly loam or gravelly clay loam in the lower part if a stone line is present. It has 15 to 27 percent clay and 0 to 10 percent gravel in the upper 10 inches and may have 5 to 25 percent gravel and 5 to 10 percent cobbles in the lower part with a stone line.
The Bt horizon is 10YR 4/4, 5/2, 5/3, 5/4, 6/2, 6/3, 6/4; or 7.5YR 5/4. Moist colors are 10YR 3/2, 3/3, 3/4, 4/2, 4/3, 4/4, 5/2, 5/4; 7.5YR 3/4 or 4/4. It is sandy clay loam, clay loam or gravelly clay loam with 25 to 40 percent clay and 5 to 35 percent rock fragments.
Some pedons have a BCt or C horizon with the same colors and textures as the Bt. It has a weaker structure and fewer clay films. It is 0 to 15 inches thick.
COMPETING SERIES: These are Annum (WA), Brownlee (ID), Chirpchatter (T CA), Dragoon (WA), Dryfalls (T WA), Ebadlow (T WA), Felton (CA), Fisherhill (T WA), Garcia (CA), Goldendale (T WA), Lompico (CA), Lorena (T WA), Meland (ID), Meystre (WA), Quiden (T WA), Rehfield (ID), Schumacher (WA), Shilly (T WA), Stacker (T WA) and Van Horn (OR) series. Annum soils have paralithic contact at 40 to 60 inches and are dry for 90 to 105 days during the summer. Brownlee, Schumacher and Van Horn are dry for 60 to 80 days and have a soil temperature of 47 to 52 degrees F. Chirpchatter, Ebadlow, Fisherhill, Goldendale, Meystre and Quiden are very deep. Dragoon and Lompico are 20 to 40 inches to paralithic contact. Dryfalls soils contain 18 to 30 percent clay and are dry for 60 to 75 days in the summer. Felton soils are 40 to 60 inches to paralithic contact, have a soil temperature of 56 to 59 degrees F and a frost-free season of 220 to 330 days and have a 14 degrees F variation between mean summer and mean winter air temperatures. Garcia, Lorena, Meland, Shilly and Stacker soils are 20 to 40 inches to a lithic contact. Rehfield soils have 18 to 30 percent clay and have a loamy sand C horizon below the Bt horizon.
GEOGRAPHIC SETTING: The Updegraff soils are on ridgetops and sideslopes of hills and mountains and have slopes of 15 to 75 percent. The soils formed in material weathered from graywacke, schist, sandstone, siltstone or shale. Elevations are 600 to 4,000 feet. The climate is subhumid with hot dry summers and cool moist winters. Mean annual precipitation varies from 40 to 70 inches. Mean January temperature is 44 degrees F; mean July temperature is 72 degrees F; and annual temperature is 47 to 58 degrees F. Frost-free season is 125 to 250 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Nashmead, Neuns, Sanhedrin, Speaker, Tyson and Woodin soils. Nashmead soils are loamy-skeletal. Neuns, Speaker, Tyson and Woodin soils are less than 40 inches to a lithic contact. Sanhedrin soils have less than 50 percent base saturation.
DRAINAGE AND PERMEABILITY: Well drained; rapid to very rapid runoff; moderately slow permeability.
USE AND VEGETATION: Use for firewood production, rangeland, watershed, wildlife habitat, recreation and limited timber production. Vegetation is Oregon white oak, California black oak, Douglas-fir, ponderosa pine, Pacific madrone, poison-oak, geyer oniongrass, blue wildrye and other annual forbs.
DISTRIBUTION AND EXTENT: Northern California in the Coast Range. The soils are moderately extensive. MLRA 5.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Mendocino County, Eastern Part, California, 1985.
REMARKS: The activity class was added to the classification in March of 2003. Competing series were not checked at that time. - ET
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 12 inches (A1, A2)
Argillic horizon - 12 to 36 inches (Bt1, Bt2, Bt3)
Lithic contact - the boundary at 45 inches. ( Highly fractured graywacke and schist)