LOCATION ZUMARIDGE CAEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, thermic Lithic Haploxerolls
TYPICAL PEDON: Zumaridge loam, on the side of a mountain at an elevation of 1810 feet. (Colors are for dry soil unless otherwise noted). Soil surface is covered with 20 percent gravel, 15 percent cobbles, and 15 percent stones.
Oe--0 to 2 inches (0 to 5 centimeters); Cenonothus leaves and sticks.
A--2 to 10 inches (5 to 25 centimeters); very dark grayish brown (10YR 3/2) loam, very dark brown (10YR 2/2) moist; few fine subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; many very fine, common fine through coarse roots; common very fine tubular pores; 5 percent pararock fragments of soft sandstone; 10 percent fine and medium subangular gravel; neutral (pH 6.6); abrupt wavy boundary. ( 7 to 20 inches thick)
Cr--10 to 13 inches (25 to 33 centimeters); soft weathered sandstone that is comprised of light yellowish brown (10YR 6/4) 85 percent pararock fragments, dark yellowish brown (10YR 4/4) moist, and 10 percent soil material in fractures that has the same colors and is a loam; abrupt wavy boundary. (0 to 6 inches thick)
R--13 inches (33 centimeters); hard yellow sandstone with fractures 4 to 8 inches apart that are 1/8 to 1/4 inch wide with soil material from above in them, and few fine roots. Sandstone is uplifted parallel to the surface.
TYPE LOCATION: Los Angeles, California; on the side of a mountain at an elevation of 1810 feet; on the north side of Castro Peak; 2800 feet north and 750 feet west of the southeast corner of section 9, T. 1 S., R. 18 W.; Latitude 34 degrees, 6 minutes, 54 seconds north and Longitude 118 degrees, 45 minutes, 54 seconds west; Point Dume Quadrangle.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 61 to 65 degrees F.
Soil moisture: Soil is moist in middle to late November to late June or early July.
Depth to hard bedrock: 10 to 20 inches.
Organic matter content: 2 to 4 percent.
A horizon--10YR 3/2, 3/3, 4/2, 4/3, 5/2 and 5/3; 10YR 2/2, 3/2, 3/3, 4/2, 4/3 moist.
Clay percentage--8 to 18 percent.
Coarse fragments--0 to 15 percent, dominantly gravel.
COMPETING SERIES: These are the Friant and the Lodo soils. Friant soils are high in mica. Lodo soils have 18 to 35 percent clay throughout.
GEOGRAPHIC SETTING: Zumaridge soils are on convex side slopes of hills and mountains. These soils formed in residuum and colluvium derived from sandstone. Slopes are 15 to 75 percent. Elevations are 600 to 3100 feet. The climate is characterized by warm, dry summers and cool, moist winters. The mean annual precipitation is 18 to 24 inches, the mean annual temperature is 59 to 63 degrees F., and the frost free season is to 290 to 320 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kawenga and Sapwi soils. All these soils are on side slopes of hills and mountains. Kawenga soils are deep and lack R horizons. Sapwi soils are moderately deep and lack R horizons.
DRAINAGE AND PERMEABILITY: Well drained; medium to very high runoff; moderate permeability.
USE AND VEGETATION: Wildlife habitat, recreation and building site development. Vegetation is Big Pod Ceonothus, Green bark Ceonothus, and miscellaneous forbs and grasses.
DISTRIBUTION AND EXTENT: Ventura County and Los Angeles County, California. The soil is not extensive. MLRA 20.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES PROPOSED: Los Angeles County, California, 2000.
REMARKS: The series name is from a local landform. Diagnostic horizons and features recognized in this pedon:
Mollic epipedon--The zone from the soil surface to a depth of about 10 inches (A horizon).
Lithic contact--The zone at a depth of 13 inches (R horizon).