LOCATION ACAMPO CAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Typic Haploxerolls
TYPICAL PEDON: Acampo sandy loam on a less than 1 percent west facing slope at an elevation of 28 feet under small grain stubble. (When described, November 11, 1980, the soil was moist below a depth of 6 inches. Colors are for dry soil unless otherwise stated).
Ap--0 to 6 inches; brown (10YR 5/3) sandy loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; many very fine roots; common very fine interstitial pores; slightly alkaline (pH 7.5); abrupt smooth boundary. (6 to 10 inches thick)
A--6 to 19 inches; brown (10YR 5/3) sandy loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; hard, very friable, nonsticky and nonplastic; common very fine roots; many very fine tubular and interstitial pores; slightly alkaline (pH 7.5); clear wavy boundary. (4 to 13 inches thick)
Bw1--19 to 26 inches; pale brown (10YR 6/3) sandy loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine roots; few very fine tubular pores; slightly alkaline (pH 7.8); gradual wavy boundary. (7 to 10 inches thick)
Bw2--26 to 37 inches; pale brown (10YR 6/3) sandy loam, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few very fine roots; many very fine tubular pores; slightly alkaline (pH 7.8); gradual wavy boundary. (9 to 13 inches)
Bq--37 to 47 inches; light yellowish brown (10YR 6/4) sandy loam, dark yellowish brown (10YR 4/4) moist; few medium dark gray (10YR 3/1) manganese stains; massive; hard, slightly brittle, nonsticky and nonplastic; continuous weakly silica cemented; few very fine tubular pores; slightly alkaline (pH 7.8); abrupt wavy boundary. (8 to 12 inches thick)
Bqkm1--47 to 49 indurated duripan with 1 to 4 mm thick laminar capping; massive; very hard; abrupt wavy boundary. (1 to 4 inches thick)
Bkqm2--49 to 60 inches; variegated yellowish brown (10YR 5/4) and brownish yellow (10YR 6/6) continuous strongly cemented duripan, dark yellowish brown (10YR 4/4) and yellowish brown (10YR 5/6) moist; few medium dark gray (10YR 3/1) manganese stains; massive; very hard, brittle; slightly effervescent with accumulations of lime in remnant pores; moderately alkaline (pH 8.0).
TYPE LOCATION: San Joaquin County, California; about 3 miles southwest of Lodi; 2,025 feet east of Lower Sacramento Road, 1,400 feet south of Armstrong Road in the NE1/4, SW1/4, NE1/4. Sec. 27, T.3N., R.6E., MDBM. Lodi South quadrangle.
RANGE IN CHARACTERISTICS: Depth to the Bq horizon is 34 to 40 inches. Depth to duripan is 40 to 60 inches. Thickness of the mollic epipedon is 12 to 19 inches. The mean annual soil temperature is 62 to 63 degrees F. The soil moisture control section is dry in all parts from June to October unless irrigated, and moist in all parts from mid-November to mid-April.
The A horizon is 10YR 5/3, 5/2; or 2.5Y 5/2. Moist color is 10YR 3/3, 3/2; or 2.5Y 3/2. Clay content is 7 to 18 percent and textures are sandy loam or fine sandy loam. Reaction is slightly acid to slightly alkaline. Organic matter is 1 to 3 percent.
The Bw and Bq horizon is 10YR 6/4, 6/3, 6/2 or 5/4. Moist color is 10YR 4/4, 4/3, 4/2 or 3/4. Clay content is 7 to 15 percent and textures are fine sandy loam, coarse sandy loam or sandy loam. Reaction is neutral to moderately alkaline.
The Bkqm horizon is 10YR 6/6, 5/6, 5/4, 7/2, 8/2; 2.5Y 7/2, or 8/1. Moist color is 10YR 5/6, 4/4, 5/3, 4/2; 2.5Y 7/2, or 5/2.
COMPETING SERIES: These are the Pfeiffer, San Andreas, Tagus (T), Tokay (T), Veritas (T) and Walong soils. San Andreas and Walong soils have a paralithic contact at 20 to 40 inches. Pfeiffer soils have up to 35 percent rock fragments in the control section and bedrock below 40 inches. Tagus soils are calcareous throughout. Tokay soils do not have pedogenic silica within 60 inches. Veritas soils are calcareous below 8 inches.
GEOGRAPHIC SETTING: The Acampo soils are on low fan terraces at elevations of 10 to 150 feet. Slopes are 0 to 2 percent. The soils formed in alluvium derived mainly from granitic rock sources. Climate is subhumid mesothermal with hot dry summers and cool moist foggy winters. Mean annual precipitation is 13 to 16 inches. Mean annual temperature is 60 to 61 degrees F. Average January temperature is 45 degrees F and average July temperature is 77 degrees F. The frost-free period is 260 to 280 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Columbia, Kingdon, San Joaquin and Tujunga soils. Columbia soils do not have a mollic epipedon and are stratified on lower positions. Kingdon soils have an argillic horizon on similar positions. San Joaquin soils have claypan subsoils over duripans and are moderately deep on higher positions. Tujunga soils have sandy textural control sections on lower positions.
DRAINAGE AND PERMEABILITY: Moderately well drained; slow runoff; moderately rapid permeability.
USE AND VEGETATION: Used for irrigated row, field, tree and vine crops and urban development. Vegetation in uncultivated areas consists of annual grasses, forbs and scattered California White Oak.
DISTRIBUTION AND EXTENT: The Acampo soils occur in the northern San Joaquin Valley. The series is of moderate extent in MLRA-17.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: San Joaquin County, California, 1990.
REMARKS: The activity class was added to the classification in January of 2003. Competing series were not checked at that time. - ET
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the surface to 19 inches (Ap, A horizons)
Cambic horizon - The zone from 19 to 37 inches (Bw1, Bw2 horizons)
Duric layer - The zone from 37 to 47 inches (Bq horizon).
Duripan- The zone from 47 to 60 inches (BqKm1, BqKm2 horizons).