LOCATION CHOICE CAEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, calcareous, thermic Typic Xerorthents
TYPICAL PEDON: Choice silty clay on a NNE slope of 25 percent, under cultivation of dryland barley (area had a harvested crop in 1979, in 1981 area has a moderately sparse stand of soft chess, wild oats, filaree, fiddleneck and mustard intermixed with barley stubble) at 1960 feet elevation. (Colors are for dry soil unless otherwise stated. When described on 10/23/79 soil was dry to 6 inches and slightly moist below.)
A1--0 to 6 inches; pale brown (10YR 6/3) silty clay, brown (10YR 4/3) moist; moderate, fine and medium subangular blocky structure; slightly hard, friable, sticky and plastic; common very fine roots; few very fine tubular pores; cracks are 1 to 2 cm wide; strongly effervescent with disseminated lime; moderately alkaline (pH 8.0); clear smooth boundary (5 to 10 inches thick).
A2--6 to 17 inches; pale brown (10YR 6/3) silty clay, brown (10YR 4/3) moist; weak medium prismatic structure parting to weak medium subangular blocky; slightly hard, friable, sticky and plastic; few very fine roots; common very fine tubular pores; strongly effervescent with disseminated lime and few fine filaments in lower part; moderately alkaline (pH 8.0); clear wavy boundary. (5 to 11 inches thick).
Bk1--17 to 32 inches; light yellowish brown (10YR 6/4) silty clay, dark yellowish brown (10YR 4/4) moist; moderate fine prismatic structure parting to moderate fine subangular blocky; hard, friable, sticky and plastic; few very fine roots; common very fine and few fine tubular pores; few pressure faces; violently effervescent with lime segregated as may fine filaments and in seams and common fine soft masses; moderately alkaline (pH 8.0); gradual wavy boundary. (15 to 20 inches thick).
Bk2--32 to 47 inches; light yellowish brown and brownish yellow (10YR 6/4 and 6/6) silty clay, yellowish brown (10YR 5/6) moist, weak fine subangular blocky structure; slightly hard, very friable, sticky and plastic; few very fine roots; common very fine tubular pores; violently effervescent with lime segregated as common fine filaments and soft masses; moderately alkaline (pH 8.0); gradual wavy boundary. (15 to 19 inches thick).
Cr--47 to 57 inches; weathered calcareous sandstone; fine and medium angular fragments that slake in water after 15 minutes of shaking.
TYPE LOCATION: San Luis Obispo County, California; approximately 4.2 miles northwest on Palo Prieta, Cholame Road from the intersection with Bitterwater Valley Road, then approximately 2.5 miles southeast on dirt road across road from farmstead, 450 feet north and 700 feet east of the southwest corner of Sec. 2, T.27S., R.17E., 172 feet from corner fence post on road, magnetic bearing 346 degrees; USGS Packwood Creek Topgraphic quadrangle; lat. 35 degrees, 36 min., 5 sec. N and 120 degrees, 7 min., 6 sec. W.
RANGE IN CHARACTERISTICS: Depth to soft calcareous sandstone or shale is 40 to 60 inches. Mean annual soil temperature ranges from 60 degrees to 67 degrees F. The moisture control section between depths of 7 and 20 inches is moist in some part from December until April and is moist in all parts for at least 45 consecutive days between January to March. The soil is dry for about 260 days and has a xeric bordering on aridic moisture regime. The soil is clay or silty clay. Calcium carbonate content ranges from 5 to 12 percent throughout the soil and has a slight increase with increasing depth.
The A horizon has dry color of 10YR 5/2, 6/2, 6/3; 2.5Y 5/2 or 6/2 and moist color of 10YR 3/2, 4/2, 4/3; 2.5Y 3/2, 4/2, or 5/2. Organic carbon is less than 0.6 percent. At depths of 5 to 17 inches cracks are 0.5 to 2 cm wider when dry. It is slightly to violently effervescent.
The B horizon has dry color of 10YR 6/2, 6/3, 6/4, 6/6 or 7/4; 2.5Y 6/2; 5Y 5/2 or 7/2 and moist color of 10YR 4/2, 4/3, 4/4, 4/6, 5/4 or 5/6; 2.5Y 3/2, 4/2 or 5/2; 5Y 4/2, or 5/2. It is strongly to violently effervescent.
COMPETING SERIES: These are the Aido, Kilmer, and Mendi series in other families. Aido soils have slickensides and wide cracks and have depths less than 40 inches to a paralithic contact. Kilmer and Mendi soils are fine-loamy.
GEOGRAPHIC SETTING: Choice soils are on hills and mountains and have slopes 5 to 30 percent. The soils formed in material weathered from soft calcareous sandstone or shale. Elevations are 1,400 to 3,500 feet. The climate is semi-arid with hot dry summers and cool moist winters. Mean annual precipitation is 8 to 12 inches. Mean January temperature is 46 degrees F., mean July temperature is 77 degrees F., mean annual temperature varies from 58 degrees to 62 degrees F. Frost-free season is 175 to 250 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Aido, Kilmer, and Mendi soils and the Naciminento soils. Nacimiento soils have mollic epipedons and are fine-loamy.
DRAINAGE AND PERMEABILITY: Well drained, medium to high runoff; slow permeability.
USE AND VEGETATION: The soil is used for dry farmed grain mostly wheat and barley and rangeland. Natural vegetation is mainly soft chess, wild oats, and filaree.
DISTRIBUTION AND EXTENT: Hills of the Temblor range in California, MLRA 15. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Kern County, Northwestern Part, California, 1982.
ADDITIONAL DATA: NSSL pedon no. 84P926