LOCATION SANTA LUCIA CAEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, mixed, superactive, thermic Pachic Ultic Haploxerolls
TYPICAL PEDON: Santa Lucia shaly clay loam, annual grass, oak rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 8 inches; very dark gray (10YR 3/1) shaly light clay loam, black (10YR 2/1) moist; weak coarse and medium subangular blocky structure, upper 3/4 to 1 inch medium to strong fine granular structure on about 3/4 of surface; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine interstitial pores; about 10 percent angular shale fragments larger than 3/4 inch and about 25 percent above 2mm; moderately acid (pH 6.0); gradual wavy boundary.
A2--8 to 17 inches; very dark gray (10YR 3/1) very shaly light clay loam, black (10YR 2/1) moist; strong fine and medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine interstitial pores; about 50 percent angular shale fragments larger than 3/4 inch and about 15 percent larger than 2mm; moderately acid (pH 6.0); gradual wavy boundary. (7 to 12 inches thick)
A3--17 to 24 inches; very dark gray (10YR 3/1) very shaly clay loam, black (10YR 2/1) moist; strong fine and medium granular structure; slightly hard, friable, sticky and plastic; many very fine roots; many very fine interstitial pores; about 50 percent shale fragments larger than 3/4 inch and about 15 percent larger than 2 mm; strongly acid (pH 5.5); abrupt irregular boundary. (5 to 20 inches thick)
R--24 to 36 inches; hard weakly fractured Monterey shale; contains some porcelaneous strata.
TYPE LOCATION: Santa Barbara County, California; 5 airline miles south and slightly west of Guadalupe in Casmalia Hills; NW1/4 NW1/4 sec. 5, T.9N., R.35W.
RANGE IN CHARACTERISTICS: Depth to a lithic contact is 20 to 40 inches. The mean annual soil temperature is 59 degrees to 65 degrees F. Soil between the depths of about 5 to 15 inches is usually dry all of the time from late April or May until November or early December and usually moist all the rest of the year. Angular and subangular shale fragments average 35 to 80 percent. Most pedons have about 35 to 50 percent fragments are more numerous in the lower part of the profile.
The A horizon is usually 3/1, 4/1, 5/1 or 6/1 but is 4/2 or 5/2 in the lower part of some pedons. Field textures are loam, clay loam or heavy clay loam but laboratory determinations indicate that most pedons have 35 to 50 percent clay. Organic matter ranges from 2 to 20 percent. The soil is slightly to strongly acid. Base saturation is between 50 and 75 percent and closer to 50 than 75 in many pedons. Structure is weak to strong subangular blocky or granular. Many pedons have moderate or strong structure. A few thin, dark colored clay films are present in the lower part of some pedons or in fractures of the underlying rock. Some pedons have a pale C horizon of soil material a few inches thick just above the bedrock. In most pedons the A horizons rest on the R layer.
COMPETING SERIES: These are the Butano, Crow Hill, Gazos, Junipero, Lopez, Lobitos, Reliz, San Benito, Sheridan, and Tollhouse series. Junipero soils have less than 35 percent rock fragments and have a mean annual soil temperature of less than 59 degrees F. Butano and Lobitos soils have an argillic horizon. Crow Hill and Gazos soils have less than 35 percent rock fragments. San Benito soils are calcareous in some part. Lopez, Reliz, and Tollhouse soils have a lithic or paralithic contact less than 20 inches below the surface and Reliz soils have an ochric epipedon. Sheridan soils have less than 18 percent clay and less than 15 percent rock fragments in the control section.
GEOGRAPHIC SETTING: Santa Lucia soils are on uplands. Elevations are 100 to 3,000 feet. The soils formed in material weathered from white shale containing some ash and some siliceous and diatomaceous material. The climate is subhumid mesothermal with cool to warm rainless but foggy summers near the coast and cool moist winters. The mean annual precipitation is 12 to 35 inches. The average January temperature is 47 degrees to 51 degrees F.; the average July temperature is 63 degrees to 68 degrees F.; the mean annual temperature is about 58 degrees to 60 degrees F. The annual freeze-free season is 175 to about 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Crow Hill, Gazos, Lopez, and Reliz soils and the Elder, Linne, Lockwood, Los Osos, Maymen and Nacimiento soils. Elder soils lack a lithic contact. Lockwood and Los Osos soils have argillic horizons. Linne and Nacimiento soils are calcareous throughout. Maymen soils have an ochric epipedon and have a lithic contact at depths of less than 20 inches.
DRAINAGE AND PERMEABILITY: Well-drained; very low to high runoff; moderate permeability.
USE AND VEGETATION: Used mostly for grazing. A few areas are farmed to small grain and minor areas of other crops. Vegetation is mostly coastal type sage with live oak and variable amounts of annual grass-form vegetation. Some open annual grass-form with scattered oak.
DISTRIBUTION AND EXTENT: Santa Lucia soils occur in the central and south-central part of the Coast Range in California, MLRA 15. The soils are extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Monterey County (King City Area), California, 1924.
OSED scanned by SSQA. Last revised by state on 3/76.