LOCATION SOQUEL             CA
Established Series
Rev. RHB/JPR/RWK/ET
03/2003

SOQUEL SERIES


The Soquel series consists of deep, moderately well drained soils that formed in alluvium derived from sedimentary rocks. Soquel soils are in narrow valleys and on alluvial fans and plains, and have slopes of 0 to 15 percent. The mean annual precipitation is about 30 inches and the mean annual air temperature is about 57 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Cumulic Haploxerolls

TYPICAL PEDON: Soquel loam, apple orchard. (Colors are for dry soil unless otherwise noted.)

Ap--0 to 7 inches; very dark grayish brown (10YR 3/2) loam, very dark gray (10YR 3/1) moist; weak fine granular and weak medium subangular blocky structure; hard, friable, sticky and slightly plastic; common very fine roots; many very fine interstitial pores; moderately acid (pH 6.0); abrupt wavy boundary. (6 to 9 inches thick)

A12--7 to 13 inches; very dark yellowish brown (10YR 3/2) loam, very dark gray (10YR 3/1) moist; moderate coarse subangular blocky structure; hard, friable, sticky and slightly plastic; many very fine, medium and coarse roots; common very fine and medium, few fine tubular pores; moderately acid (pH 6/2); clear wavy boundary. (6 to 8 inches thick)

A13--13 to 21 inches; brown (10YR 4/3) loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure; hard, friable, sticky and slightly plastic; few very fine, many medium and coarse roots; common very fine and few fine tubular pores; slightly acid (pH 6.5); gradual wavy boundary. (8 to 10 inches thick)

C1--21 to 37 inches; brown (10YR 5/3) silt loam, brown (10YR 4/3) moist and dark brown (10YR 3/3) rubbed moist; common fine distinct dark grayish brown (10YR 4/2) and brownish yellow (10YR 6/6) mottles, very dark grayish brown (10YR 3/2) moist; moderate coarse subangular blocky structure; hard, friable, sticky and plastic; few very fine, many medium and coarse roots; few thin tubular pores; neutral (pH 6.6); clear wavy boundary. (14 to 18 inches thick)

A1b--37 to 51 inches; brown (10YR 5/3) silty clay loam, dark yellowish brown (10YR 3/4) moist and dark brown (10YR 3/3) rubbed moist; common fine distinct dark grayish brown (10YR 4/2) and light yellowish brown (10YR 6/4) mottles, very dark grayish brown (10YR 3/2) moist; weak coarse subangular blocky structure; hard, friable, sticky and plastic; few very fine, many medium and coarse roots; many very fine, common fine tubular pores; neutral (pH 6.8); gradual wavy boundary. (10 to 18 inches thick)

IIC2--51 to 62 inches; yellowish brown (10YR 5/4) heavy loam, dark brown (10YR 3/3) moist and dark yellowish brown (10YR 4/4) moist rubbed, common fine distinct dark brown (10YR 3/3) and very pale brown (10YR 7/4) mottles, brown (7.5YR 4/4) moist; weak coarse subangular blocky structure; hard, friable, sticky and plastic; few very fine, common medium roots; common very fine and fine tubular pores; neutral (pH 6.8).

TYPE LOCATION: Santa Cruz County, California; about 160 feet northwesterly of mail box 161, Varni Road, and 36 feet northernly from Varni Road in the NE1/4 NE1/4 NE1/4 section 24, T.11S., R.1E.

RANGE IN CHARACTERISTICS: The soil between depths of 6 to 18 inches is usually dry in all parts for at least 45 consecutive days between mid-July and mid-October and is usually moist in all parts for more than 45 consecutive days from the end of December to the end of April. The mean annual soil temperature is about 56 to 58 degrees F. Organic matter is more than 1 percent at a depth of 20 inches and decreases irregularly with increasing depth. Base saturation is more than 50 percent in all parts and less than 75 percent in some or all parts of the profile to a depth of 30 inches. The profile is medium acid to neutral throughout. Pebbles average 0 to 15 percent by volume.

The A horizon is very dark gray, very dark grayish brown, dark gray, dark grayish brown, dark brown, or grayish brown (10YR 3/1, 3/2, 4/1, 4/2, 4/3, 5/2). It is heavy sandy loam, loam, silt loam, clay loam, or silty clay loam.

Some pedons have a horizon designated as a B horizon with color of light yellowish brown or very pale brown (10YR 6/4, 7/4). Texture is heavy sandy loam, loam, silt loam, clay loam, or silty clay loam.

The C horizon is dark brown, dark grayish brown, dark yellowish brown, brown or yellowish brown (10YR 3/3, 4/2, 4/3, 4/4, 5/3, 5/4). It is loam, silt loam, or silty clay loam. In some pedons are narrow lenses of sandy loam, loamy sand, or sand with 0 to 25 percent pebbles by volume.

COMPETING SERIES: These are the Birdow, Blackrock, Dagor, Eastcan, Goose Creek, Lakeview, Monroe and Willowdale series. All of these soils have a frost free season of between 50 to 170 days and a mean annual soil temperature of between 47 and 53 degrees F. Also, Birdow, Blackrock, Eastcan, and Willowdale soils are calcareous, at least in some part. Lakeview soils are mildly alkaline or moderately alkaline in the C horizon and are slightly calcareous in the lower part. Monroe soils lack mottles.

GEOGRAPHIC SETTING: Soquel soils are in narrow valleys and on alluvial fans and plains typically on the first and second bottoms, and have slopes of 0 to 15 percent. They formed from sedimentary alluvium. Elevations are 20 to 1,000 feet. The climate is subhumid mesothermal having warm, dry but foggy summers and cool, moist winters. The mean annual precipitation is 25 to 50 inches. The average January temperature is 46 degrees F.; to average July temperature is 66 degrees F.; and the mean annual temperature is 54 to 58 degrees F. The frost free season is about 220 to 275 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aptos, Conejo, Danville, Elder, Elkhorn, Felton, Lompico, and Nisene soils. Aptos, Felton, Lompico, and Nisene soils have a B2t horizon, and in addition, Aptos and Lompico soils have a paralithic contact at depths of 20 to 40 inches. Conejo and Elder soils have a mean annual soil temperature warmer than 59 degrees F. and Elder soils have less than 18 percent clay. Danville and Elkhorn soils have a mean soil temperature warmer than 59 degrees F. and a B2t horizon.

DRAINAGE AND PERMEABILITY: Moderately well drained; slow or medium runoff; moderately well drained permeability.

USE AND VEGETATION: Used for apple orchards, bushberries, strawberries, irrigated row crops, timber production, and in some areas homesites. Vegetation is redwood, oak, tanoak, poison oak, shrubs and ferns.

DISTRIBUTION AND EXTENT: Valleys of the central California coast. The soils are inextensive.

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

SERIES ESTABLISHED: Santa Cruz Area, California, 1935.

REMARKS: The activity class was added to the classification in February of 2003. Competing series were not checked at that time. - ET


National Cooperative Soil Survey
U.S.A.