LOCATION CURRYMOUNTAIN CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Argixerolls
TYPICAL PEDON: Currymountain loam on a north facing slope of 53 percent under California juniper, goldenbush, wild cucumber, Brodiaea, soft chess, fescue, filaree, buckwheat, and fiddleneck. The elevation is 1,760 feet. (Color is for dry soil unless otherwise stated. When described April 30, 1991, the soil was moist throughout.)
A--0 to 3 inches; brown (10YR 5/3) loam, dark brown (10YR3/3) moist; moderate medium and fine subangular blocky structure; hard, very friable, slightly sticky and moderately plastic; few very fine and fine roots; many very fine tubular pores; slightly acid (pH 6.5); abrupt smooth boundary. (2 to 6 inches thick).
Bt1--3 to 7 inches; brown (10YR 5/3) clay loam, dark brown (10YR 3/3) moist; moderate medium and coarse subangular blocky structure; hard, friable, moderately sticky and moderately plastic; very few fine and very fine roots; many very fine tubular pores; very few moderately thick clay films on ped faces and bridging mineral grains; slightly acid (pH 6.5); abrupt wavy boundary. (4 to 12 inches thick).
Bt2--7 to 13 inches; brown (10YR 5/3) clay loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; very few very fine and fine and few medium roots; many very fine tubular pores; few moderately thick clay films on ped faces and bridging mineral grains; neutral (pH 6.6); clear wavy boundary. (4 to 15 inches thick).
C1--13 to 18 inches; yellowish brown (10YR 5/4) clay loam, brown (10YR 4/3) moist; massive; hard, friable, moderately sticky and moderately plastic; very few fine and few medium and coarse roots; many very fine tubular pores; neutral (pH 6.6); clear smooth boundary. (4 to 12 inches thick).
C2--18 to 24 inches; yellowish brown (10YR 5/4) clay loam, brown (10YR 4/3) moist; massive; hard, very friable, moderately sticky and moderately plastic; very few fine and few medium and coarse roots; many very fine tubular pores; neutral (pH 6.7); abrupt smooth boundary. (5 to 10 inches thick.)
Cr--24 inches; highly fractured weathered shale.
TYPE LOCATION: Fresno County, California; approximately 5 miles southwest of the community of Coalinga on the southeastern flank of Curry Mountain. Approximately 2,560 feet south and 380 feet west of the northeast corner of section 27, T. 21 S., R.14 E., MDB&M; Latitude 36 degrees, 4 minutes, 29 seconds north and Longitude 120 degrees, 26 minutes, 24 seconds west; USGS Curry Mountain Topographic Quadrangle, NAD 27.
RANGE IN CHARACTERISTICS: Depth to a paralithic contact of marine sandstone and shale ranges from 20 to 40 inches. The moisture control section between the depths of 4 and 12 inches is moist in some or all parts from December 1 to June 1 and dry from July 1 to October15 in most years. The soil temperature is above 47 degrees F. from April 15 to November 15. The mean annual soil temperature is 56 to 58 degrees F. Some pedons have an A2 horizon, that is 6 to 10 inches thick. Some pedons do not have a C horizon.
The A horizon has color of 7.5YR 4/3; 10YR 4/2, 4/3, 4/4, 5/2, 5/3, 5/4, 6/3 or 2.5Y 4/2. Moist color is 7.5YR 3/3; 10YR 2/1, 3/1, 3/2, 3/3 or 2.5Y 3/2. Organic matter content is 1 to 2 percent. Clay content is 15 to 27 percent. Gravel content is 0 to 14 percent. Reaction is slightly acid or neutral.
The Bt horizon has color of 7.5YR 3/4, 4/3, 4/4, 5/3, 6/4; 10YR 4/2, 4/3, 4/4, 5/2, 5/3, 5/4, 6/3, 6/4 or 2.5Y 5/4. Moist color is 5YR 3/4; 7.5YR 3/2, 3/3, 3/4, 4/3, 4/4; 10YR 2/2, 3/2, 3/3, 3/4, 4/2, 4/3, 4/4 or 2.5Y 4/4. Dry values of 6 or moist chromas of 4 occur only below the mollic epipedon. Organic matter content is 1 to 2 percent. Texture is loam or clay loam. Clay content is 18 to 35 percent. Gravel content is 0 to 14 percent. Cobble content is 0 to 10 percent. Reaction is slightly acid or neutral.
The C horizon has color of 7.5YR 3/4, 4/4; 10YR 5/4 or 6/3. Moist color is 7.5YR 3/4; 10YR 3/3, 4/3 or 4/4. Organic matter content is 0.1 to 0.5 percent. Texture is loam or clay loam. Clay content is 18 to 35 percent. Gravel content is 0 to 14 percent. Cobble content is 0 to 10 percent. Reaction is slightly acid or neutral.
COMPETING SERIES: These are the Ahsahka, Buckbay, Elkheights, Foehlin, Jauriga, Picketpin, Sagaser and Tweedy series. Ahsahka soils (MLRA 43) are very deep soils on benches, hills, canyon sideslopes and footslopes and do not have a paralithic contact. Buckbay soils (MLRA 21) are on hills and are formed in colluvium and residuum from andesite with mean annual soil temperature of 47 to 52 degrees F. and have color hue of 7.5YR or redder. Elkheights soils (MLRA 44) are very deep soils on hillslopes formed in loess and alluvium over glacial till. Foehlin soils (MLRA 5) are very deep soils on alluvial fans and low terraces and are formed in alluvium from metamorphic, granitic and ultramafic rocks. Jauriga soils (MLRA 21) are on mountain sideslopes and toeslopes and formed in material weathered from andesite or basalt and have mean annual soil temperature from 47 to 52 degrees F. Picketpin soils (MLRA 10) are on foothills, do not have a paralithic contact, are very deep and have an E and B horizon with lamellae in the subsoil. Sagaser soils (MLRA 15) are on mountains and are 40 to 60 inches deep to a paralithic contact. Tweedy soils (MLRA 18, 26) are formed in material weathered from mica schist and igneous rocks and have color hue of 7.5YR or redder in B and C horizons.
GEOGRAPHIC SETTING: Currymountain soils are on mountains, commonly on north aspects. Slope is 30 to 50 percent. Elevation is 899 to 3,520 feet. These soils formed in material weathered from marine sandstone and shale. The climate is subhumid with hot dry summers and cool moist winters. The mean annual precipitation is 9 to 14 inches. The mean January temperature is 45 degrees F; and the mean July temperature is 80 degrees F. The mean annual temperature is 55 to 58 degrees F. The frost-free season is 200 to 240 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Delgado, Gaviota, Hentine, Grazer, Lilten, Millsholm, Quinto, Roacha and Sagaser soils. Delgado soils, on hills, have an aridic moisture regime and are shallow to a lithic contact. Gaviota, Hentine, Millsholm and Quinto soils, on mountains, are shallow to a lithic contact. Grazer, Lilten and Roacha soils, on mountains, have a fine particle-size control section. Sagaser soils, on mountains, are deep to a paralithic contact.
DRAINAGE AND PERMEABILITY: Well drained; very high runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for livestock grazing and for recreation and wildlife habitat. The vegetation is California juniper, blue oak, foothill pine, soft chess, pine bluegrass, and miners lettuce.
DISTRIBUTION AND EXTENT: These soils are in the Diablo Range in the California Coast Ranges. They are moderately extensive. MLRA 15.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Fresno County, California, 2002. Named after Curry Mountain, a dominant geologic feature on the landscape where this soil occurs.
REMARKS:
1. Mollic epipedon--the zone from the surface of the soil to a depth of 13 inches (A, Bt1, Bt2 horizons)
2. Argillic horizon and fine-loamy particle-size control section--the zone from 3 inches to a depth of 13 inches (Bt1, Bt2 horizons)