LOCATION SHERIDAN CAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Pachic Haploxerolls
TYPICAL PEDON: Sheridan coarse sandy loam - grass range (Colors are for dry soil unless otherwise noted.)
A11--0 to 8 inches; Dark grayish brown (10YR 4/2) coarse sandy loam, very dark brown (10YR 2/2) moist; moderate medium and coarse subangular blocky structure; slightly hard, very friable, slightly sticky, slightly plastic; many very fine roots; many very fine interstitial pores; top one inch strong fine and medium granular structure with mat of very fine roots; rest of horizon somewhat compacted by trampling; slightly acid (pH 6.5); gradual smooth boundary. (7 to 10 inches thick)
A12--8 to 18 inches; Dark grayish brown (10YR 4/2) coarse sandy loam, very dark brown (10YR 2/2) moist; strong medium and coarse granular structure; slightly hard, very friable, slightly sticky, slightly plastic; common very fine roots; many very fine interstitial and few fine and medium tubular pores; slightly acid (pH 6.2); gradual smooth boundary. (10 to 12 inches thick)
A13--18 to 28 inches; Dark grayish brown (10YR 4/2) coarse sandy loam, very dark brown (10YR 2/2) moist; strong medium granular structure; slightly hard, very friable, slightly sticky, slightly plastic; few very fine roots; many very fine interstitial and few fine tubular pores; slightly acid (pH 6.2); gradual smooth boundary. (6 to 12 inches thick)
A14--28 to 39 inches; Dark grayish brown (10YR 4/2) coarse sandy loam, very dark grayish brown (10YR 3/2) moist; strong medium granular structure; slightly hard, very friable, slightly sticky, slightly plastic; few very fine roots; many very fine interstitial and few fine tubular pores; lower part has some indistinct dark brown (10YR 3/2 moist) lumps of Cl material; slightly acid (pH 6.2); clear wavy boundary. (6 to 12 inches thick)
C1--39 to 43 inches; Mixed brown (7.5YR 5/4) and very dark gray (10YR 3/1) weathered granite that crushes to loamy coarse sand, similar colors moist (7.5YR 4/4, 10YR 3/1); massive; hard, firm, nonsticky, nonplastic; few very fine roots; few thin clay films line pores and major rock joints, many colloidal stains on grains; has rock structure, easily cut with hand tools when moist; slightly acid (pH 6.5); gradual wavy boundary. (0 to 5 inches thick)
C2--43 to 57 inches; Similar to above (10YR 5/3, 3/1 dry and 5/3, 5/1 moist); very hard dry with few colloidal stains.
TYPE LOCATION: Monterey County, California; 3.5 miles east up Johnson Canyon Road from Armstrong Ranch; 250 feet west of E1/4 corner sec. 30, T.5S., R.6E.
RANGE IN CHARACTERISTICS: Depth to a paralithic contact of weathered granite is 25 to 40 inches. The mean annual soil temperature is about 59 F. to 64 F. and the soil temperature usually is not below 47 F. at any time. The soils between depths of about 8 and 25 inches usually are dry all of the time from May until November or early December and are moist in some or all parts all the rest of the year. The 10 to 40 inch control section is sandy loam or coarse sandy loam or light loam with less than 18 percent clay.
The A horizon is dark gray, grayish brown, dark grayish brown, very dark grayish brown or dark brown. It has weak to strong granular or subangular blocky structure. This horizon ranges from medium acid to neutral. It has 1 to 5 percent organic matter in all parts to a depth of more than 20 inches and less than 1 percent within a depth of 30 inches. Base saturation is 75 to 95 percent.
A C horizon of sandy loam or loamy sand soil material is present in some pedons above the weathered rock and in other pedons the A horizons grade directly to weathered rock.
COMPETING SERIES: These are the Anacapa, Arroyo Seco, Elder, Pfeiffer, Pico, San Andreas, and Shaver series. Anacapa soils are calcareous in the lower part and lack a paralithic contact. Arroyo Seco and Pico soils have mollic epipedons less than 20 inches thick and lack a paralithic contact. Elder soils are stratified and lack a paralithic contact. Pfeiffer and San Andreas soils have mollic epipedons less than 20 inches thick and Pfeiffer soils have a paralithic contact below a depth of 40 inches. Shaver soils have base saturation of 50 to 75 percent and a mean annual soil temperature of less than 59 F.
GEOGRAPHIC SETTING: The Sheridan soils are moderately sloping to very steep and are on hills at elevations of 1,000 to 3,000 feet on north or south slopes and up to 5,000 feet6 on south facing slopes. They formed in residuum weathered from granite, schist, and related rocks. The climate is subhumid, mesothermal with warm dry summers and cool moist winters. Mean annual precipitation is 16 to 50 inches. Average January temperature is about 48 F. to 52 F.; average July temperature is about 70 F.; mean annual temperature is about 57 F. to 63 F. The freeze-free season is 170 to 250 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cieneba, Junipero, Miramar, and Sur soils. Cieneba soils lack a mollic epipedon and are less than 20 inches deep to a paralithic contact. Junipero soils are on cool slopes with an annual soil temperature of less than 59 F. Sur soils have more than 35 percent rock fragments. Miramar soils have an argillic horizon.
DRAINAGE AND PERMEABILITY: Well-drained; medium to very runoff; moderately rapid permeability.
USE AND VEGETATION: Used for grazing and watershed. Vegetation is annual grass and forbs, oak trees, and some brush.
DISTRIBUTION AND EXTENT:
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Sacramento Area, California, 1904.
REMARKS: The Sheridan soils were formerly classified as Regosolic Brunizems. The type location was moved to place it in extensive representative areas of the series as now recognized.
ADDITIONAL DATA: Riverside Laboratory, Sample No. S65Calif-27-24. Not yet published.
The activity class was added to the classification in February of 2003. Competing series were not checked at that time. - ET
OSED scanned by SSQA. Last revised by state on 1/73.