LOCATION HIPUK CAEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, thermic, shallow Typic Haploxeralfs
TYPICAL PEDON: Hipuk gravelly sandy loam, in an area of Rock Outcrop-Sumiwawa-Hipuk Complex, 30 to 75 percent slopes; on the side of a mountain at an elevation of 1,460 feet. (Colors are for dry soil unless otherwise noted). Surface is covered with 2 percent stones, 5 percent cobbles and 40 percent gravel.
A1--0 to 1 inches (0 to 2.5 centimeters); dark grayish brown (10YR 4/2) gravelly sandy loam, very dark gray (10YR 3/1) moist; moderate thin platy structure; soft, very friable, slightly sticky and slightly plastic; common very fine roots; common very fine interstitial pores; 20 percent gravel, 3 percent cobbles, and 1 percent stones; moderately acid (pH 6.0); abrupt smooth boundary. (0 to 2 inches thick)
A2--1 to 4 inches (2.5 to 8 centimeters); dark grayish brown (10YR 4/2) sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine roots; common fine tubular pores; 10 percent gravel and 2 percent cobbles; moderately acid (pH 6.0); clear wavy boundary. (2 to 6 inches thick)
Bt1--4 to 8 inches (8 to 20 centimeters); brown (10YR 4/3) sandy clay loam, very dark yellowish brown (10YR 3/4) moist; weak fine and medium subangular blocky structure; slightly hard, very friable, moderately sticky and slightly plastic; few very fine roots; many fine tubular pores; few thin clay films on ped faces and lining pores; 10 percent gravel and 2 percent cobbles; strongly acid (pH 5.5); clear wavy boundary. (2 to 8 inches thick)
Bt2--8 to 18 inches (20 to 45 centimeters); light yellowish brown (10YR 6/4) gravelly sandy clay loam, dark yellowish brown (10YR 4/4) moist; weak medium angular blocky structure; slightly hard, very friable, moderately sticky and slightly plastic; few very fine through medium roots; many fine tubular pores; many moderately thick clay films on ped faces and lining pores; 25 percent gravel and 9 percent cobbles; strongly acid (pH 5.5); irregular wavy boundary. (4 to 14 inches thick)
Cr--18 to 24 inches (45 to 60 centimeters); highly fractured sandstone with fractures 1 to 3 inches apart, and with about 10 to 15 percent soil in fractures with few very fine through coarse roots.
R--24 to 26 inches (60 to 65 centimeters); hard, non-fractured sandstone.
TYPE LOCATION: Los Angeles County, California; about 1/2 mile south of Calabasas Peak; 2850 feet west 830 feet north of the southeast corner of section 3, T. 1 S., R. 17 W.; Latitude 34 degrees, 6 minutes, 26 seconds north and Longitude 118 degrees, 39 minutes, 0 seconds west; Malibu Beach Quadrangle.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 62 to 66 degrees F.
Soil moisture: Soil is moist in middle to late November to late May.
Depth to paralithic contact: 14 to 20 inches.
Depth to lithic contact: 20 to 40 inches.
A horizon--10YR 5/2, 5/3, 4/2, 4/3; 10YR 3/1, 3/2, 3/3 moist.
Texture--Sandy loam or gravelly sandy loam.
Clay percentage--8 to 18 percent.
Coarse fragments--5 to 35 percent.
B horizon--10YR 6/4, 6/3, 5/2, 5/3, 4/2, 4/3; 10YR 4/4, 4/3, 4/2, 3/1, 3/2, 3/3 moist.
Texture--Sandy clay loam, gravelly sandy clay loam, gravelly sandy loam, or sandy loam.
Clay percentage--18 to 27 percent.
Coarse fragments--10 to 35 percent.
COMPETING SERIES: There are no other soils in this family.
GEOGRAPHIC SETTING: Hipuk soils on are side slopes of hills and mountains and have slopes of 30 to 75 percent. They formed in residuum and colluvium derived from sandstone at elevations of 1,400 to 2,500 feet. The mean annual precipitation is 18 to 24 inches. Mean annual temperature is 60 to 64 degrees F. The frost-free season is 290 to 350 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kawenga (t), Sumiwawa (t) and Zumaridge (t) soils. All these soils occur on the side slopes of hills and mountains. Sumiwawa soils lack argillic horizons and have sandy particle size families. Kawenga soils are 40 to 60 inches to soft rock and have mollic epipedons. Zumaridge soils are less than 20 inches to a lithic contact and have mollic epipedons.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderately slow permeability.
USE AND VEGETATION: Used for recreation, building site development and wildlife habitat. Vegetation is chamise ceonothus, Laural sumac, and miscellaneous forbs and grasses.
DISTRIBUTION AND EXTENT: Los Angeles County, California. The soil is of limited extent. 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 American Indian name. Diagnostic horizons and features recognized in this pedon:
Ochric epipedon--The zone from the soil surface to a depth of about 4 inches (A1 and A2 horizons).
Argillic horizon--The zone from a depth of 4 inches to a depth of about 18 inches (Bt1 and Bt2 horizons).
Paralithic material--The zone from a depth of 18 inches to about 24 inches (Cr horizon).
Lithic contact--The zone at about 24 inches (R horizon).