LOCATION BUREN CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Haplic Durixeralfs
TYPICAL PEDON: Buren fine sandy loam - cultivated. (Colors are for dry soil unless otherwise noted).
Ap1--0 to 7 inches; yellowish brown (10YR 5/4) fine sandy loam, dark brown (10YR 3/3) moist; massive; slightly hard, very friable, slightly sticky, plastic; common fine and medium roots; common fine tubular pores; moderately alkaline (ph 8.0); abrupt smooth boundary. (5 to 8 inches thick)
Ap2--7 to 12 inches; brown (10YR 5/3) fine sandy loam, dark yellowish brown (10YR 4/4) moist; massive; hard, friable, slightly sticky, plastic; few fine random roots; common fine tubular pores; compacted by tillage; moderately alkaline (pH 8.0); clear smooth boundary. (4 to 6 inches thick)
B21t--12 to 19 inches; brown (7.5YR 4/4) clay loam, dark brown (7.5YR 4/4) moist; strong coarse angular blocky structure; very hard very firm, very sticky, very plastic; common fine random roots; common fine tubular pores; moderately thick clay films on faces of peds; moderately alkaline (pH 8.0); gradual smooth boundary. (5 to 7 inches thick)
B22tca--19 to 28 inches; pale brown (10YR 6/3) clay loam, brown (10YR 4/3) moist; moderate fine angular blocky structure; very hard, very firm, sticky, plastic; few fine random roots; common fine tubular pores; common moderately thick clay films on faces of peds; strongly effervescent, medium filaments and threads and medium round soft masses of light gray (10YR 7/2) lime; moderately alkaline (pH 8.4); clear smooth boundary. (7 to 10 inches thick)
B3ca--28 to 37 inches; light olive brown (2.5Y 5/4) loam, olive brown (2.5Y 4/4) moist; massive; very hard, firm, slightly sticky, plastic; few fine random roots; many fine tubular pores; bridges and few thin clay films line tubular pores; slightly effervescent, fine filaments and threads of lime; moderately alkaline (pH 8.4); clear smooth boundary. (6 to 9 inches thick)
C1si--37 to 47 inches; yellowish brown (10YR 5/4) loam, dark yellowish brown (10YR 4/4) moist; very coarse prismatic structure; weakly cemented; very hard, firm, slightly sticky, plastic; many fine tubular pores; sides of prisms are faced with thin lime and silica coatings of light yellowish brown (10YR 6/4); slightly effervescent, fine threads and filaments of calcium carbonate; moderately alkaline (pH 8.4); gradual smooth boundary. (8 to 14 inches thick)
C2si--47 to 52 inches; light yellowish brown (10YR 6/4) loam, brown (10YR 4/3) moist; massive; very hard, firm, slightly sticky, plastic; common fine tubular pores; about 30 percent of mass appears to be durinodes; slightly effervescent, fine threads and filaments of calcium carbonate; moderately alkaline (pH 8.4).
TYPE LOCATION: Riverside County, California; 1,400 feet south and 200 feet west of NE corner of sec. 17, T. 3 S., R. 5 W.
RANGE IN CHARACTERISTICS: Depth to the weakly cemented horizon ranges from 27 to 40 inches. There are less than 1 to about 10 percent rock fragments in the solum. The mean soil temperature is about 65 degrees F, and is never below 47 degrees F. The soils are continuously moist in some part between depths of 4 and 12 inches from about mid-December until May and are continuously dry all the rest of the time.
The Buren series have yellowish brown and brown, moderately alkaline, fine sandy loam A horizons. The A horizon is grayish brown, pale brown or yellowish brown with chroma of 2 through 4 and value of 5 or 6. It contains less than 1 percent organic matter. It is fine sandy loam or loam. This horizon is slightly hard or hard, and the immediate surface may or may not be both massive and hard. It ranges from slightly acid to moderately alkaline and is not calcareous.
They have brown and pale brown, moderately alkaline, clay loam B2t horizons. The B2t horizon has the following Munsel notations: 10YR 6/3, 5/2, 5/3, 5/4, 4/3 and 7.5YR 6/4, 5/4, and 4/4. It is heavy loam, clay loam, or silty clay loam with about 20 to 30 percent clay. This horizon ranges from slightly acid to moderately alkaline, but only the lower part is calcareous. The lower B2t and/or B3 horizon have lime segregations.
They have yellowish brown, weakly cemented Csi horizons. The C1si horizon has a clear or abrupt upper boundary and roots do not penetrate except along prism faces. The upper surface does not generally have opal coating or the surface is only very thinly coated. Thin silica and lime coatings are more prominent on prism faces than on the tops. The Csi horizon is yellowish brown to light brownish gray, or light yellowish brown in 10YR or 2.5Y hue. It is firm or extremely firm and very hard. This horizon is brittle to somewhat brittle and does not slake after prolonged immersion in water.
COMPETING SERIES: These are the Arlington, Betteravia, Chesterton, Redding, Rocklin, San Joaquin, Yokohl, and Ysidora series. Arlington soils have less than 18 percent clay in the argillic horizon. Betteravia soils have thick sandy A horizons. Chesterton, Redding, and San Joaquin soils have abrupt upper boundaries to an argillic horizon that has more than 35 percent clay. Rocklin soils have a continuous opal coating at the top of the duripan which is also indurated in thin sheets. Yokohl soils have more than 35 percent clay. Ysidora soils have more than 10 percent rock fragments and the dominant hue is 2.5YR or 5YR in the argillic horizon.
GEOGRAPHIC SETTING: These soils are on gently to strongly sloping alluvial fans and terraces at elevations of about 700 to 3,000 feet. The soils formed in alluvium derived mostly from basic igneous rocks and partly from other crystalline rocks. They occur in a semiarid mesothermal climate with an average annual precipitation of 12 to 15 inches, an average January temperature of 51 degrees F, and average July temperature of 76 degrees F, and an average annual temperature of 61 to 65 degrees F. The frost-free season is about 230 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Arlington, Fallbrook, Las Posas, Ramona, and Wyman soils. Fallbrook and Las Posas soils developed in residuum from rock and have a lithic or paralithic contact. Ramona and Wyman soils lack silica cementation.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderately slow permeability in the Bt horizon and very slow in the Csi horizon.
USE AND VEGETATION: Production of citrus, small grains, and pasture are the principal uses. The natural vegetation is principally annual grasses and forbs with chaparral shrubs on eroded terrace slopes.
DISTRIBUTION AND EXTENT: The soils are limited to the intermediate valleys of southern California. They are inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Riverside County, California, 1971.
REMARKS: The Buren soils were formerly classified as Noncalcic Brown soils.
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 5/72.