LOCATION BLUESTONE CAEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, nonacid, thermic Lithic Xerorthents
TYPICAL PEDON: Bluestone clay-on north facing convex slope of 9 percent under fallow farmland at 2,900 feet elevation. (Colors are for dry soil unless otherwise stated. When described on 6/8/77 the soil was dry 0 to 4 inches and moist below 4 inches.)
A11--0 to 1 inches; brown (7.5YR 5/4) clay, dark brown (7.5YR 4/4) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, very sticky and very plastic; few very fine roots; many very fine interstitial pores; about 10 percent shale fragments; mildly alkaline (pH 7.5); abrupt smooth boundary. (1 to 2 inches thick0
A12--1 to 12 inches; brown (7.5YR 5/4) clay, dark brown (7.5YR 4/4) moist; moderate coarse prismatic structure parting to moderate coarse subangular blocky; very hard, firm, very sticky and very plastic; few very fine roots; few very fine interstitial and tubular pores; about 10 percent shale fragments; mildly alkaline (pH 7.5); clear wavy boundary. (6 to 12 inches thick)
C--12 to 16 inches; brown (7.5YR 5/4) clay, dark brown (7.5YR 4/4 moist; massive; hard, firm, very sticky and very plastic; few very fine roots; few very fine interstitial pores; about 20 percent shale fragments; mildly alkaline (pH 7.5); clear wavy boundary. (3 to 6 inches thick)
R--16 to 17 inches; hard, fractured, noncalcareous shale.
TYPE LOCATION: Kern County, California; about 10 miles southwest of Blackwell's Corner in the Temblor Range; 20 feet southeast of dirt road on top of knoll, about 1,050 feet west of old barn; in the NW1/4, SW1/4, NE1/4 of section 33T., 28S., R.19E.
RANGE IN CHARACTERISTICS: Depth to lithic contact ranges from 10 to 20 inches. Mean annual soil temperature is 60 degrees F. The soil between depths of 6 to 16 inches is usually dry all of the time from April 15 to November 15 and is moist in some or all parts all the rest of the year. The moisture regime is xeric bordering on aridic. Some pedons may contain 5 to 10 percent cobble sized shale fragments. The soil is neutral or mildly alkaline.
Color of the A horizon is 7.5YR 5/4; 10YR 5/3, 5/4. Moist color is 7.5YR 4/4; 10YR 3/4. It is clay, silty clay, or clay loam. Shale fragments range from 0 to 15 percent and are 2 mm to 100 mm in diameter.
Colors of the C horizon are similar to the A horizon. It is shaly clay or shaly clay loam. Shale fragments range from 15 to 35 percent and are 2 mm to 100 mm in diameter.
COMPETING SERIES: These are the Daulton, Exchequer, and Gaviota series in other families. These soils have a loamy textural class and a mixed mineralogy.
GEOGRAPHIC SETTING: Bluestone soils are on uplands, mainly hillslopes. Slopes are 9 to 60 percent. The soils formed in material weathered from noncalcareous shale. Elevations are 2,000 to 3,500 feet. The climate is subhumid mesothermal with warm, dry summers and cool, moist winters. Mean annual precipitation is 8 to 10 inches. Mean January temperature is 44 degrees F.; mean July temperature is 81 degrees F.; mean annual temperature is 57 degrees to 61 degrees F. Frost-free season is 200 to 250 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Aido (T), Ayar, and Hillbrick soils. Aido soils are 20 to 40 inches deep. Ayar soils have deep, wide cracks and are 40 to 80 inches deep. Hillbrick soils have loamy textural control sections.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; slow permeability.
USE AND VEGETATION: Used for dryland grain, rangeland, watershed, and wildlife. Vegetation is annual grasses, forbs, scattered oaks and junipers.
DISTRIBUTION AND EXTENT: The Temblor Range of California. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Kern County, Northwestern Part, California, 1982.