LOCATION CAJALCO CATentative Series
TAXONOMIC CLASS: Fine-loamy, mixed, active, thermic Mollic Haploxeralfs
TYPICAL PEDON: Cajalco fine sandy loam - annual grass pasture. (Colors are for dry conditions unless otherwise noted).
Ap1--0 to 3 inches; yellowish brown (10YR 5/4) fine sandy loam, dark yellowish brown (10YR 3/4) moist; weak medium granular structure; weakly coherent, very friable, nonsticky and nonplastic; abundant very fine roots; many very fine interstitial pores; slightly acid (pH 6.5); clear, smooth boundary. (2 to 5 inches thick)
Ap2--3 to 10 inches; yellowish brown (10YR 5/4) fine sandy loam, dark yellowish brown (10YR 3/4) moist; weak medium granular structure to massive; slightly hard, very friable, slightly sticky and nonplastic; abundant very fine and few medium roots; many very fine interstitial and tubular pores; slightly acid (pH 6.5); gradual, wavy boundary. (2 to 8 inches thick)
B1--10 to 13 inches; brown (7.5YR 5/4) fine sandy loam, dark reddish brown (5YR 3/4) moist; weak coarse subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; abundant very fine roots; many very fine tubular pores; few thin clay films line tubular pores; neutral (pH 7.0); gradual, wavy boundary. (3 to 7 inches thick)
B2t--13 to 18 inches; brown (7.5YR 5/4) loam, dark reddish brown (5YR 3/4) moist; moderate medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; plentiful very fine roots; many very fine tubular pores; few thin clay films line tubular pores; neutral (ph 7.0); clear, wavy boundary. (4 to 15 inches thick)
B3t--18 to 22 inches; light yellowish brown (10YR 6/4) loam, dark yellowish brown (10YR 4/4) moist; massive; hard, friable, slightly sticky and nonplastic; plentiful very fine roots; many very fine tubular pores; neutral (pH 7.0); gradual, wavy boundary. (3 to 11 inches thick)
C1--22 to 30 inches; light yellowish brown (10YR 6/4) well weathered gabbro, yellowish brown (10YR 5/4) moist; massive; hard, friable, nonsticky and nonplastic; slightly alkaline (ph 7.5); gradual, wavy boundary. (4 to 22 inches thick)
C2--30 to 62 inches; light gray (10YR 6/1) weathered gabbro, gray (10YR 5/1) moist; massive; very hard, very friable, nonsticky and nonplastic; slightly acid (pH 6.5). (Many feet thick)
TYPE LOCATION: Riverside County, California; approximately 1,350 feet north, 800 feet west of the southeast corner sec. 22, T. 4 S., R. 5 W., about 80 miles south of Arlington, California.
RANGE IN CHARACTERISTICS: The climate is one of long, dry summers and short, mild winters. Depth to weathered rock may range from 18 to 46 inches.
The Cajalco soils have yellowish brown, slightly acid, moderately coarse textured A horizons. The A horizons range from brown to dark brown to yellowish brown, with hues of 10YR or 7.5YR, values of 4 or 5 dry, 3 or 4 moist, and chromas of 3 or 4, from sandy loam to loam, and neutral to slightly acid.
The Cajalco soils have brown, slightly acid, medium textured Bt horizons. The B2t horizon ranges from brown to reddish brown, with hues of 7.5YR to 5YR, and values of 4 or 5 dry, 3 or 4 moist, from sandy loam to clay loam, and neutral to slightly acid.
The subsurface horizons commonly are higher in reaction than the surface, although there is no consistent trend in reaction with depth. They developed in deeply weathered gabbro. Small soft masses or seams of lime sometimes occur in the weathered gabbro.
COMPETING SERIES: The Cajalco soils resemble those of the Escondido, Fallbrook, Las Posas, Soper, and Tivy series. The Escondido soils are developed on metasedimentary rocks, and lack argillic horizons. The Fallbrook soils are developed on deeply weathered acid igneous rocks, and have reddish brown to strong brown Bt horizons. The Las Posas soils have red to dark reddish brown Bt horizons with more than 35 percent clay. The Soper soils are developed in gravelly marine sediments, and have brown to reddish brown Bt horizons. The Tivy soils have brown to dark brown Bt horizons in hues of 10YR.
GEOGRAPHIC SETTING: The Cajalco soils occur on gently sloping to steep uplands in areas of deeply weathered, basic igneous rocks at elevations of less than 3,500 feet. The climate is one of long, dry summers and short, mild winters, with 9 to 16 inches average annual rainfall. The average January temperature is 50 degrees F, the average July temperature 72 degrees F, and the average annual temperature 62 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: The Cajalco soils are associated with those of the Auld, Buren, Las Posas, Vina, and Wyman series. The Auld soils are fine textured throughout the solum; the Buren soils are developed in alluvium from basic igneous rocks, and have weak duripans in the lower part of the solum; the Vina soils are developed in alluvium from basic igneous rocks, have dark colored surface horizons, and lack diagnostic subsurface horizons. The Wyman soils are also developed in alluvium from basic igneous rocks.
DRAINAGE AND PERMEABILITY: The Cajalco soils are well drained, moderately permeable, with medium run-off.
USE AND VEGETATION: They are used mostly for range or wildlife; in some localities they have been planted to citrus and other subtropical fruits. The native vegetation consists of annual grasses and chaparral shrubs.
DISTRIBUTION AND EXTENT: The Cajalco soils occur in the foothills and interior valleys of Southern California; they are of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Western Riverside Area, California, 1958.
REMARKS: The Cajalco soils were formerly classified in the Noncalcic Brown soils, University of California profile group VII.
The activity class was added to the classification in January of 2003. Competing series were not checked at that time. - ET
Last revised by the state on 8/66.