LOCATION CASCARA CA

Established Series
Rev. KDA-BRY-KP
12/2022

CASCARA SERIES

The Cascara series consists of very shallow, well drained soils on mountain slopes. These soils formed in colluvium over residuum derived from serpentinite. Slope is 30 to 65 percent. The mean annual precipitation is about 53 centimeters (21 inches) and the mean annual temperature is about 15 degrees C. (59 degrees F).

TAXONOMIC CLASS: Loamy, magnesic, nonacid, thermic, shallow Typic Xerorthents

TYPICAL PEDON: Cascara gravelly coarse sandy loam; on an east facing slope of 60 percent under scattered, sparse bigberry manzanita, and Coulter pine. The elevation is 939 meters (3,080 feet). (Color is for dry soil unless otherwise stated. When described on April 22, 2009 the soil was slightly moist throughout). The surface is covered by 60 percent 2 to 20 millimeter serpentine pebbles and 10 percent 20 to 75 millimeter serpentine pebbles.

A--0 to 5 centimeters (0 to 2 inches); strong brown (7.5YR 4/6) gravelly coarse sandy loam, strong brown (7.5YR 5/6) moist; weak thin platy structure; soft, very friable, slightly sticky and slightly plastic; common very fine interstitial and tubular pores; 18 percent 2 to 20 millimeter pebbles; slightly alkaline (pH 7.7); abrupt smooth boundary.

Bt--5 to 18 centimeters (2 to 8 inches); brown (7.5YR 4/4) sandy loam, strong brown (7.5YR 5/6) moist; weak thin platy parting to weak fine subangular structure; soft, very friable, slightly sticky and slightly plastic; common very fine interstitial pores; few distinct clay films on ped faces and along surface of pores; 11 percent 2 to 20 millimeter pebbles; slightly alkaline (pH 7.7); abrupt smooth boundary.

Cr--18 to 70 centimeters (8 to 27 inches); weakly cemented serpentinite.

TYPE LOCATION: San Benito County, California, in Clear Creek Management Area; about 1 kilometer (0.6 miles) northwest of Clear Creek Mine; about 549 meters (1,800 feet) south and 279 meters (915 feet) west of the northeast corner of section 11, T. 18 S., R. 11 E., Mount Diablo Base and Meridian; latitude 36 degrees 22 minutes 41.5 seconds north and longitude 120 degrees 43 minutes 45.7 seconds west; USGS Idria, California, Quadrangle, NAD83.

RANGE IN CHARACTERISTICS: Depth to paralithic contact is 10 to 25 centimeters (4 to 10 inches). Surface fragments are composed of serpentinite; 30 to 80 percent, 5 to 20 millimeter pebbles and 5 to 20 percent, 20 to 75 millimeter pebbles.

A horizon:
Hue: 7.5YR and 10YR dry and moist
Value: 5 or 6 dry and 3 or 4 moist
Chroma: 2 to 6 dry and moist
Texture of the fine earth fraction: coarse sandy loam or sandy loam
Content of clay: 8 to 12 percent
Content of organic matter: 0.1 to 0.3 percent
Reaction: neutral to moderately alkaline
Content of rock fragments: 15 to 34 percent, 2 to 20 millimeter pebbles

Bt horizon:
Hue: 7.5YR and 10YR dry and moist
Value: 5 or 6 dry and 4 moist
Chroma: 4 to 6 dry and 2 to 4 moist
Texture of the fine earth fraction: sandy loam
Content of clay: 8 to 12 percent
Content of organic matter: 0.1 to 0.3 percent
Reaction: neutral to moderately alkaline
Content of rock fragments: 10 to 34 percent, 2 to 20 millimeter pebbles

COMPETING SERIES: There are no competing series at this time.

GEOGRAPHIC SETTING: Cascara soils are on mountain slopes at elevations of 816 to 1,532 meters (2,677 to 5,026 feet). Slope is 30 to 65 percent. Cascara soils formed in colluvium over residuum derived from serpentinite. The climate consists of hot dry summers and cool moist winters. Mean annual precipitation is 483 to 610 millimeters (19 to 24 inches). Mean annual temperature is 14 to 17 degrees C. (57 to 63 degrees F). Frost-free season is 150 to 200 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Atravesada, Delmexico, Flomack, and Idriapeak soils. Atravesada soils have a mollic epipedon. Delmexico soils have a mollic epipedon and are deep to a paralithic contact. Flomack soils have an argillic horizon and are shallow to a paralithic contact. Idriapeak soils are moderately deep to a paralithic contact and have a loamy-skeletal particle size class.

DRAINAGE AND PERMEABILITY: Well drained; medium to high runoff; high saturated hydraulic conductivity.

USE AND VEGETATION: These soils are used for recreation and wildlife. The vegetation is usually nonexistent (barren) with scattered bigberry Manzanita and Coulter pine.

DISTRIBUTION AND EXTENT: These soils are in the Clear Creek Management Area, San Benito and Fresno Counties, CA, in the California Coast Ranges. They are not extensive. MLRA 15.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES PROPOSED: San Benito County, California, 2009. Name is coined .

REMARKS: The modal pedon ID for the Cascara Series is 09CA069007 (Pedon Number 09N0926). Magnesic mineralogy class is supported by the lab data and the serpentinite parent material.

ADDITIONAL DATA: Mean annual soil temperature at a depth of 50 cm (20 inches) is 15 degrees C (59 degrees F) at the typical profile site, based on 1 year's data (8/1/2009-8/1/2010) measured with an Onset Soil Temperature Recorder.

National Cooperative Soil Survey
U.S.A.