LOCATION TECUYA CA

Tentative Series
Rev. KJO/MRS/KDA/KP
12/2022

TECUYA SERIES

The Tecuya series consists of very deep, well drained soils that formed in residuum derived from calcareous sandstone, shale, and/or conglomerate. These soils are on hillslopes. Slope is 9 to 50 percent. The mean annual precipitation is about 254 mm (10 in) and the mean annual temperature is about 18 degrees C (62 degrees F).

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, thermic Typic Calcixerolls

TYPICAL PEDON: Tecuya loam, on a north facing slope of 14 percent under annual grasses and forbs at an elevation of 663 meters (2,175 feet) (). [When described on November 06, 1989, the soil was slightly moist from 51 to 152 cm (20 to 60 in). Colors are for dry soil unless otherwise stated.]

A1--0 to 8 cm (0 to 3 in); brown (10YR 5/3) cobbly silt loam, dark brown (10YR 3/3) moist; 7 percent clay; moderate medium platy structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; common very fine tubular pores; calcium carbonate equivalent of 4 percent; violently effervescent; carbonates disseminated; 10 percent calcareous sandstone gravel and 5 percent calcareous sandstone cobbles; moderately alkaline (pH 8.0); abrupt smooth boundary.

A2--8 to 23 cm (3 to 9 in); brown (10YR 5/3) cobbly silt loam, dark brown (10YR 3/3) moist; 7 percent clay; weak coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; common very fine tubular pores; calcium carbonate equivalent of 4 percent; violently effervescent; carbonates segregated as few fine threads; 10 percent calcareous sandstone gravel and 5 percent calcareous sandstone cobbles; moderately alkaline (pH 8.2); clear wavy boundary.

Bk1--23 to 71 cm (9 to 28 in); very pale brown (10YR 8/4) very cobbly silt loam, light yellowish brown (10YR 6/4) moist; 15 percent clay; weak medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common very fine roots; common very fine and fine tubular pores; calcium carbonate equivalent of 8 percent; violently effervescent; carbonates disseminated and segregated as many fine threads and few medium soft masses; 10 percent calcareous sandstone gravel and 30 percent calcareous sandstone cobbles; moderately alkaline (pH 8.2); clear wavy boundary.

Bk2--71 to 97 cm (28 to 38 in); very pale brown (10YR 8/4) very cobbly loam, light yellowish brown (10YR 6/4) moist; 20 percent clay; weak coarse subangular blocky structure parting to weak medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine and fine tubular pores; calcium carbonate equivalent of 8 percent; strongly effervescent; carbonates disseminated and segregated as few fine threads and few medium soft masses; 10 percent calcareous sandstone gravel and 30 percent calcareous sandstone cobbles; moderately alkaline (pH 8.2); clear wavy boundary.

Bk3--97 to 152 cm (38 to 60 in); very pale brown (10YR 8/3) extremely gravelly loam, pale brown (10YR 6/3) moist; 20 percent clay; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine tubular pores; calcium carbonate equivalent of 8 percent; strongly effervescent; carbonates disseminated and segregated as few fine threads and medium soft masses; 90 percent calcareous sandstone cobbles; moderately alkaline (pH 8.2).

TYPE LOCATION: Kern County, California, Southwest part; in map unit 461, Geghus-Tecuya association, 30 to 75 percent slopes; about 2 kilometers (1 miles) northeast of Grapevine; 436 meters (1,430 feet) south and 174 meters (570 feet) east of the northeast corner of section 22 (projected onto the land grant), T. 10 N., R. 19 W.; San Bernardino Base and Meridian; latitude 34 degrees 56 minutes 15 seconds north and longitude 118 degrees 54 minutes 15 seconds west; USGS Grapevine, California, Quadrangle, NAD83.

RANGE IN CHARACTERISTICS:

Soil temperature: Average annual is 16 to 18 degrees C (60 to 64 degrees F) and the soil temperature is rarely below 8 degrees C (47 degrees F). The soils have a thermic temperature regime.

Soil moisture: The soils have a xeric soil moisture regime. The soil moisture control section is dry throughout from about late June to early December in most years and moist in some or all parts during the rest of the year.

Diagnostic feature(s):
Mollic epipedon thickness: 18 to 50 cm
Calcic horizon thickness: 50 to 150 cm

Particle size control section weighted average:
Rock fragments: 35 to 60 percent gravel
Clay content: 10 to 30 percent
Reaction: slightly to strongly alkaline

Surface fragments: 2 to 30 percent gravel, 0 to 10 percent cobbles, 0 to 10 percent stones, and 0 to 2 percent boulders consisting of sedimentary rock.

A horizons:
Hue: 10YR
Value: 4 or 5 dry, 3 moist
Chroma: 2 or 3, dry or moist
Texture of the fine earth fraction: loam, silt loam
Content of clay: 5 to 18 percent
Content of organic matter: 1.0 to 2.0 percent
Calcium carbonate equivalent: 2 to 5 percent
Content of rock fragments: 7 to 25 percent
5 to 15 percent gravel
2 to 10 percent cobbles

Upper Bk horizons (Bk1 and Bk2):
Hue: 10YR
Value: 7 or 8 dry, 5 or 6 moist
Chroma: 3 or 4, dry or moist
Texture of the fine earth fraction: loam, clay loam, silt loam
Content of clay: 10 to 30 percent
Content of organic matter: 0.1 to 1.3 percent
Calcium carbonate equivalent: 5 to 10 percent
Content of rock fragments: 20 to 50 percent
0 to 15 percent gravel
15 to 50 percent cobbles

Lower Bk horizons (Bk3):
Hue: 10YR
Value: 7 or 8 dry, 5 or 6 moist
Chroma: 3 or 4, dry or moist
Texture of the fine earth fraction: loam, clay loam, silt loam
Content of clay: 18 to 30 percent
Content of organic matter: 0.1 to 1.3 percent
Calcium carbonate equivalent: 5 to 10 percent
Content of rock fragments: 60 to 90 percent
0 to 15 percent gravel
60 to 90 percent cobbles

COMPETING SERIES: There are no competing series at this time.

GEOGRAPHIC SETTING: The Tecuya soils are on hillslopes. Slope is 9 to 50 percent. The Tecuya soils formed in residuum derived from calcareous sandstone, shale, and/or conglomerate. Elevations are 412 to 1,476 meters (1,350 to 4,840 feet). The climate is semiarid with hot dry summers and cool moist winters. Mean annual precipitation is 203 to 254 mm (8 to 10 in). The mean annual temperature is 16 to 18 degrees C (61 to 64 degrees F). Mean July temperature is about 79 degrees F, and mean January temperature is about 8 degrees C (43 degrees F). Frost-free season ranges from 200 to 300 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Balcom, Balhud, Beam, Bitcreek, Geghus, Harrisranch, Loslobos, and Shimmon soils. Balcom soils, on hills, are moderately deep and have a fine-loamy particle-size class. Balhud soils, on hillslopes, are shallow, have an argillic horizon, and have a fine-loamy particle-size class. Beam soils, on hills and mountains, are shallow, have a cambic horizon, and have a loamy particle-size class. Bitcreek soils, on hillslopes, have an argillic horizon, have a pachic epipedon, and have a fine-loamy particle-size class. Geghus soils, on hillslopes and mountain slopes, have an argillic horizon and have a fine-loamy particle-size class. Harrisranch soils, on mountain slopes, have a coarse-loamy particle-size class, have a pachic (thick) mollic epipedon, and have a mesic temperature regime. Loslobos soils, on hills and mountain slopes, have a pachic (thick) mollic epipedon and have a coarse-loamy particle-size class. Shimmon soils, on hills and mountains, are moderately deep, have an argillic horizon, and have a fine-loamy particle-size class.

DRAINAGE AND PERMEABILITY: Well drained; high runoff; moderately high saturated hydraulic conductivity.

USE AND VEGETATION: These soils are used for livestock grazing. Vegetation is ripgut brome, fiddleneck, redstem filaree, wild oats, soft chess and annual forbs.

DISTRIBUTION AND EXTENT: Transverse Range and associated hills of Sierra Nevada Foothills (MLRA 18). The series is not extensive.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Davis, California

SERIES PROPOSED: Kern County, California, 1991. The name is from nearby Tecuya Creek.

REMARKS:
Particle Size Control Section for this pedon: 48 to 98 cm.
Diagnostic horizons and features recognized in this pedon are:
Mollic Epipedon 0 to 23 cm
Calcic Horizon 23 to 71 cm

Soil classified using the 12th Edition of the Keys to Soil Taxonomy.

National Cooperative Soil Survey
U.S.A.