LOCATION BULL TRAIL CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Mollic Haploxeralfs
TYPICAL PEDON: Bull Trail sandy loam, annual grass pasture. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 8 inches; grayish brown (10YR 5/2) sandy loam, very dark grayish brown (10YR 3/2) moist; weak granular structure; soft, very friable, nonsticky and nonplastic; many fine roots; moderately acid (pH 6.0); clear smooth boundary. (6 to 12 inches thick)
B21t--8 to 11 inches; brown (10YR 5/3) coarse sandy clay loam, dark grayish brown (10YR 4/2) moist; moderate medium subangular blocky structure; very hard, friable, slightly sticky and slightly plastic; common fine and medium roots; many fine and few medium tubular pores; common moderately thick clay films on faces of peds; moderately acid (pH 6.0); clear smooth boundary. (2 to 8 inches thick)
B22t--11 to 16 inches; brown (10YR 5/3) coarse sandy clay loam, dark grayish brown (10YR 4/2) moist; moderate medium angular blocky structure; very hard, firm, slightly sticky and slightly plastic; common fine roots; common fine tubular pores; common moderately thick clay films on faces of peds; moderately acid (pH 6.0); gradual smooth boundary. (5 to 9 inches thick)
B23t--16 to 22 inches; brown (10YR 5/3) coarse sandy clay loam, dark grayish brown (10YR 4/2) moist; moderate medium angular blocky structure; very hard, firm, sticky and slightly plastic; common fine roots; common fine tubular pores; few moderately thick clay films on faces of peds; moderately acid (pH 6.0); gradual smooth boundary. (4 to 12 inches thick)
B3t--22 to 30 inches; yellowish brown (10YR 5/4) coarse sandy loam, dark yellowish brown (10YR 4/4) moist; massive; hard, firm, slightly sticky and slightly plastic; common fine roots; common fine tubular pores; common thin clay films on faces of peds; slightly acid (pH 6.5); gradual smooth boundary. (4 to 12 inches thick)
C1--30 to 45 inches; yellowish brown (10YR 5/4) loam, dark yellowish brown (10YR 4/4) moist; massive; hard, friable, slightly sticky and slightly plastic; few fine roots; many fine interstitial pores; neutral (pH 6.7); gradual smooth boundary. (10 to 20 inches thick)
C2--45 to 55 inches; yellowish brown (10YR 5/4) coarse sandy loam, dark yellowish brown (10YR 4/4) moist; massive; slightly hard, friable, nonsticky and nonplastic; many fine interstitial pores; neutral (pH 7.0); abrupt smooth boundary. (8 to 12 inches thick)
C3--55 to 60 inches; pale brown (10YR 6/3) fine sandy loam, brown (10YR 4/3) moist; massive; very hard, firm, slightly sticky and slightly plastic; few very fine tubular pores; neutral (pH 7.0).
TYPE LOCATION: Riverside County, California; about 6 miles northeast of Aguanga; approximately 1,280 feet west, 1,000 feet south of E1/4 corner section 5, T.8S., R.2E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature at a depth of 20 inches is about 56 to 58 degrees F. and the soil temperature is not below 47 degrees F. after about the 10th of February. Soil between the depths of about 6 and 18 inches usually is moist in some or all parts from about December 1 until late May and usually is dry all the rest of the year. The A and B horizons have up to 15 percent rock fragments, mostly 2 mm to 3/4 inch in diameter. Some pedons have stones and cobblestones on the surface. The C horizon has up to 35 percent rock fragments but most pedons have less than 15 percent.
The A or Ap horizon is grayish brown or brown in 10YR or 7.5YR hue and is coarse sandy loam, sandy loam or fine sandy loam. It has 1.5 to 3 percent organic matter in the upper part that decreases regularly to less than 1 percent 5 to 9 inches below the surface.
The B2t horizon is brown, light brown, light yellowish brown or yellowish brown in 10YR or 7.5YR hue and is heavy sandy loam, sandy clay loam or loam and has 18 to 27 percent clay. It is moderately acid to slightly alkaline and the base saturation is more than 75 percent.
The C horizon is pale brown, light yellowish brown, yellowish brown or light brownish gray. It is dominantly sandy loam, but is somewhat stratified and texture ranges from loamy sand to loam. In some pedons there are some lenses weakly cemented by silica or lime or both.
COMPETING SERIES: These are the Bancas, Blakeport, Chualer, Dozel, Hilt, Kitchen Creek, Mary and Morical series. Bancas, Dozel, and Hilt soils have a paralithic contact 20 to 40 inches below the surface. Blakeport and Morical soils have a paralithic contact within 40 inches of the surface and are dry for 60 to 80 days. Chauler and Kitchen Creek soils have a mollic epipedon. Also, Chualar soils have a 59 to 63 degree F. mean annual soil temperature and Kitchen Creek soils have less than 18 percent clay. Mary soils have a lithic contact at a depth of 20 to 40 inches.
GEOGRAPHIC SETTING: The Bull Trail soils are on gently sloping to moderately steep and are on alluvial fans and terraces at elevations of 2,700 to 5,600 feet. The climate is subhumid mesothermal with long dry summers and terraces at elevations of 2,700 to 5,600 feet. The climate is subhumid mesothermal with long dry summers and moist winters. The average annual precipitation is 13 to 25 inches of which about 1/2 falls as snow. The average January temperature is 40 degrees F.; the average July temperature is 68 degrees F.; and the average annual temperature is 52 to 56 degrees F. The average frost free season is 150 to 200 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Calpine, Crouch, La Posta, Mottsville, Oak Glen, and Tollhouse soils. Calpine, Crouch, La Posta, Mottsville, and Oak Glen soils have a mollic epipedon and lack an argillic horizon. Tollhouse soils lack an argillic horizon and have a paralithic contact at a depth of less than 20 inches.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderately slow permeability.
USE AND VEGETATION: Used mainly for range or pasture. Native vegetation is mainly chaparral shrubs, and naturalized annual forbs and grasses.
DISTRIBUTION AND EXTENT: Mountain valleys of southern California. They are moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Riverside County, California, 1973.
REMARKS: Where the colors are dark the organic carbon or thickness of the epipedon does not qualify for a mollic epipedon.
The activity class was added to the classification in January of 2003. Competing series were not checked at that time. - ET