LOCATION BENRIDGE CAEstablished Series
TAXONOMIC CLASS: Fine, mixed, active, thermic Mollic Palexeralfs
TYPICAL PEDON: Benridge loam--on a southwest facing convex slope of 42 percent under blue oak, chamise, manzanita, toyon, poison oak, and annual grasses at 1,600 feet elevation. (Colors are for dry soil unless otherwise stated. When described on May 21, 1979, the soil was dry to a depth of 21 inches and moist below.)
A--0 to 6 inches; light brown (7.5YR 6/4) loam, dark reddish brown (5YR 3/4) moist; moderate fine granular and strong medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine medium roots; common fine and medium interstitial and few medium and coarse tubular pores; 12 percent pebbles 2 to 15 mm in diameter; slightly alkaline (pH 7.4); abrupt wavy boundary. (5 to 6 inches thick)
Bt1--6 to 21 inches; yellowish red (5YR 4/6) gravelly clay loam, dark reddish brown (5YR 3/4) moist; strong medium and coarse subangular blocky structure; hard, friable, sticky and plastic, weakly smeary; few very fine and fine roots; common very fine interstitial and common fine and course tubular pores; many moderately thick clay films on peds and in pores; 17 percent pebbles 2 to 50 mm in diameter; neutral (pH 7.3); clear wavy boundary. (12 to 16 inches thick)
Bt2--21 to 50 inches; yellowish red (5YR 4/6) gravelly clay loam, dark reddish brown (5YR 3/4) moist; moderate fine and medium subangular blocky structure; hard, friable, sticky and plastic, weakly smeary; few very fine roots; common very fine and fine interstitial and common medium and few coarse tubular pores; many moderately thick clay films on peds and in pores; 25 percent pebbles 2 to 50 mm in diameter and 2 percent cobbles to 10 cm in diameter; neutral (pH 6.8); gradual smooth boundary. (13 to 30 inches thick)
Bt3--50 to 63 inches; yellowish red (5YR 5/6) gravelly clay loam, red (2.5YR 4/6) moist; moderate fine and medium subangular blocky structure; hard, friable, sticky and plastic, weakly smeary; few very fine roots; common very fine and fine interstitial and tubular pores; 20 percent pebbles 2 to 50 mm in diameter; many thick clay films on peds and in pores; neutral (pH 6.6); gradual smooth boundary. (12 to 17 inches thick)
Bt4--63 to 68 inches; yellowish red (5YR 5/6) clay, reddish brown (5YR 4/4) moist; strong fine and medium subangular blocky structure; very hard, firm, sticky and plastic, weakly smeary; few very fine interstitial and tubular pores; 8 percent pebbles to 50 mm in diameter; many thick clay films on peds and in pores; neutral (pH 6.6), abrupt irregular boundary. (0 to 17 inches thick)
R--68 inches; volcanic breccia.
TYPE LOCATION: Lake County, California; 20 feet east of Konocti Road at a point 600 feet north of the lowest hairpin bend. It is 2,600 feet south and 2,000 feet east of the northwest corner of sec. 13, T. 13 N., R. 9 W.; Kelseyville quadrangle, MDB&M.
RANGE IN CHARACTERISTICS: The solum is 60 to 80 inches thick. The mean annual soil temperature varies from 59 to 63 degrees F. The soil between depths of 6 inches and 19 inches is moist in all parts from January 1 through March 30 and is dry in all parts from June 1 through October 15. Soil is influenced by some amorphous material. The clay content continues to increase with depth to more than 60 inches.
The A horizon dry color is 7.5YR 6/2, 6/4; or 10YR 6/3, 6/4. Moist color is 7.5YR 3/4; 10YR 3/4 or 5YR 3/4. It is neutral or mildly alkaline. Gravel content is 5 to 15 percent. Clay content is 15 to 25 percent.
The Bt horizon dry color is 5YR 4/6, 5/6, 6/4 or 6/6. Moist color is 5YR 3/4, 4/4, 4/6 or 2.5YR 4/6. Chromas of 6 occur in at least the lower part of the argillic horizon. It is clay, gravelly clay, clay loam, or gravelly clay loam. The particle-size control section ranges from 35 to 50 percent clay. Gravel content is 5 to 25 percent. Cobble content is 0 to 5 percent. It is weakly or moderately smeary.
COMPETING SERIES: This is the Hellman and Honker series. Hellman soils lack any amorphous properties. Honker soils are 20 to 40 inches deep to a lithic contact and have an abrupt A/Bt boundary.
GEOGRAPHIC SETTING: The Benridge soils occur on hills and mountains. Slopes are 8 to 75 percent. Elevations are 1,300 to 4,300 feet. The soils are formed in volcanic ash, breccia, or tuff. The climate is subhumid with hot dry summers and cool moist winters. Mean annual precipitation varies from 25 to 40 inches. Mean January temperature is about 42 degrees F; mean July temperature is about 68 degrees F. The mean annual temperature is about 57 degrees F. The frost-free season is 140 to 205 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the competing Konocti soil and the Bottlerock, Collayomi, Sodabay, and Whispering soils. Bottlerock and Collayomi soils are loamy-skeletal. Sodabay soils are fine-loamy. Whispering soils are 20 to 40 inches deep to a lithic contact.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff, moderately slow permeability.
USE AND VEGETATION: Used mainly for homesite development, watershed, wildlife habitat and some cropland producing walnuts. Natural vegetation consists of blue oak, chamise, manzanita, toyon, poison oak, and annual grasses.
DISTRIBUTION AND EXTENT: Clear Lake volcanic field, Lake County, California. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Lake County, California, 1983.
REMARKS: The activity class was added to the classification in January of 2003. Competing series were not checked at that time. - ET
Last revised by the state on 3/85.