LOCATION CALERA CAEstablished Series
The Calera soils usually occur at elevations below 1,500 feet in a subhumid mesothermal climate having a mean annual rainfall of 22 to 30 inches with warm, dry summers and cool, moist, winters; an average January temperature of about 50 degrees F.; an average July temperature of about 57 degrees F; a mean annual temperature of about 53 degrees F.; and a frost free season of over 250 days.
The Calera soils occur in the same general area as the Gazos, Montara, and Sweeney soils. The Permanente soils are also developed on limestone but are stony and shallow and brown (7.5YR) to reddish brown.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, isomesic Pachic Haploxerolls
TYPICAL PEDON: Calera loam.
A1--0 to 10 inches; very dark grayish brown (10YR 3/2) loam, very dark brown (10YR 2/2) when moist; moderate fine granular structure; hard when dry, friable when moist; abundant very fine and fine roots; many very fine and fine pores; moderate organic matter content; mildly alkaline, pH 7.5, very slightly calcareous; gradual, smooth lower boundary. 4 to 12 inches thick.
C--10 to 30 inches; brown (10YR 4/3) clay loam, very dark grayish brown (10YR 3/2) when moist; moderate medium granular structure; slightly hard when dry, friable when moist; plentiful very fine to medium roots; many very fine and fine pores; common fragments of limestone, increasing in amount with depth; mildly alkaline, pH 7.8, slightly calcareous; abrupt, irregular lower boundary. 0 to 50 inches thick.
Dr--30 inches +; white and dark gray (N 8/ or 10YR 4/1) crystalline limestone that is fractured in the upper portion and contains a very small amount of yellowish brown (10YR 5/4) clay loam, (10YR 4/4) when moist, along fracture planes; many feet thick.
RANGE IN CHARACTERISTICS: The soil varies mainly in the depth to bedrock, from very shallow to very deep. The C horizon may be absent in very shallow profiles.
GEOGRAPHIC SETTING: Usually steep or very steep with occasional sloping areas.
DRAINAGE AND PERMEABILITY: Well to somewhat excessively drained; slow to moderately rapid runoff depending on slope and soil depth; moderate permeability.
USE AND VEGETATION: Mainly for watershed. Some areas are mined for limestone. Mainly coyote brush (Baccharis) with some grass and oaks.
DISTRIBUTION AND EXTENT: Central portion of the Coast Range Mountains of California.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: San Mateo District, California, 1941.
SOURCE OF NAME: Calera Valley, about 6 miles north of Montara in San Mateo County, California.
TYPE LOCATION: Near the west quarter corner of section 28, T. 4 S., R. 5 W., about 100 yards north of point where road turns north along the east lobe of Pilarcitos Lake, between the two lobes, in San Matao County, California.
REMARK: This soil is classified as follows: USDA Yearbook: Rendzina, Revised Classification: 5.110, Univ. of Calif., Storie & Weir: Rendzina, Profile Group VIII.
OSED scanned by SSQA. Last revised by state on 4/60.