LOCATION GEGHUS CA
Established Series
Rev. KJO/MRS/KDA/KP
09/2013
GEGHUS SERIES
The Geghus series consists of very deep, well drained soils that formed in residuum derived from calcareous shale, sandstone, and/or conglomerate. The Geghus soils are on hillslopes and mountain slopes. Slope is 9 to 75 percent. The mean annual precipitation is about 254 millimeters (10 inches) and the mean annual temperature is about 17 degrees C. (62 degrees F.).
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Typic Argixerolls
TYPICAL PEDON: Geghus loam, with a northwest aspect (307 degrees); on a 36 percent slope, under annual grasses and forbs at an elevation of 663 meters (2,175 feet). (Colors are for dry soil unless otherwise stated. When described on July 18, 1991, the soil was slightly moist from 51 to 157 centimeters (20 to 62 inches)).
A--0 to 5 centimeters (0 to 2 inches); brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; moderate thick platy structure parting to moderate medium platy; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; few very fine tubular pores; slightly alkaline (pH 7.5); abrupt smooth boundary. (5 to 36 centimeters [2 to 14 inches] thick.)
Bt1--5 to 15 centimeters (2 to 6 inches); brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; strong coarse angular blocky structure parting to strong medium angular blocky; hard, friable, slightly sticky and slightly plastic; common very fine roots; common very fine tubular pores; few faint clay films on faces of peds and along surfaces of pores; 3 percent 2 to 75 millimeter gravel; moderately alkaline (pH 8.0); clear wavy boundary. (10 to 15 centimeters [4 to 6 inches] thick.)
Bt2--15 to 38 centimeters (6 to 15 inches); brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure; slightly hard, very friable, slightly sticky and plastic; common very fine roots; common very fine tubular pores; common faint clay films on faces of peds and along surface of pores; slightly effervescent; carbonates disseminated; 3 percent 2 to 75 millimeter gravel; moderately alkaline (pH 8.0); clear irregular boundary. (15 to 25 centimeters [6 to 10 inches] thick.)
Btk1--38 to 74 centimeters (15 to 29 inches); brown (10YR 5/3) clay loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and plastic; few very fine roots; common very fine, few fine and few medium tubular pores; common distinct clay films on faces of peds and along surfaces of pores; strongly effervescent; carbonates disseminated and segregated as many fine threads; moderately alkaline (pH 8.0); 3 percent 2 to 75 millimeter gravel; clear wavy boundary.( 30 to 38 centimeters [12 to 15 inches] thick.)
Btk2--74 to 112 centimeters (29 to 44 inches); pink (7.5YR 7/4) clay loam, brown (7.5YR 5/4) moist; weak coarse subangular blocky structure; slightly hard, very friable, slightly sticky and plastic; few very fine roots; common very fine, few fine and few medium tubular pores; many distinct clay films on faces of peds and along surfaces of pores; strongly effervescent; carbonates disseminated and segregated as common fine threads and coatings along surfaces of pores; 3 percent 2 to 75 millimeter gravel; moderately alkaline (pH 8.0); clear wavy boundary. (30 to 51 centimeters [12 to 20 inches] thick.)
Btk3--112 to 137 centimeters (44 to 54 inches); pink (7.5YR 7/4) clay loam, brown (7.5YR 5/4) moist; massive; slightly hard, very friable, slightly sticky and plastic; few very fine roots; common very fine, few fine and few medium tubular pores; common distinct clay films bridging sand grains and along surfaces of pores; strongly effervescent; carbonates disseminated and segregated as common fine threads and coatings along surfaces of pores; 3 percent 2 to 75 millimeter gravel; moderately alkaline (pH 8.0); abrupt wavy boundary. (20 to 30 centimeters [8 to 12 inches] thick.)
Btk4--137 to 157 centimeters (54 to 62 inches); pink (7.5YR 7/4) loam, brown (7.5YR 5/4) moist; massive; slightly hard, very friable, slightly sticky and plastic; few very fine roots; common very fine tubular pores; common faint clay films bridging sand grains and along surfaces of pores; strongly effervescent; carbonates disseminated and segregated as few fine threads; moderately alkaline (pH 8.0).
TYPE LOCATION: Kern County , California, Southwest Part; in map unit 460, Geghus-Tecuya association, 9 to 30 percent slopes; about 1.1 kilometers (0.7 miles) west of the Grapevine truck stop; 76 meters (250 feet) north and 213 meters (700 feet) west of the southeast corner of the projected section 19; T. 10 N., R. 19 W.; San Bernardino Base and Meridian; latitude 34 degrees, 55 minutes, 57 seconds latitude and longitude 118 degrees, 57 minutes, 07 seconds west; USGS Grapevine, California, Quadrangle, NAD83.
RANGE IN CHARACTERISTICS:
Soil temperature: Average annual is 16 to 18 degrees C. (61 to 64 degrees F.) and the soil temperature is rarely below 8 degrees C. (47 degrees F.).
Soil moisture: Dry throughout from late June to early December in most years; moist in some or all parts during the rest of the year.
About 0 to 5 percent of the surface is covered by 2 to 75 millimeter gravel consisting of sandstone.
A horizon:
Hue: 10YR dry and moist
Value: 5 or 6 dry and 3 moist
Chroma: 2 or 3 dry and moist
Texture of the fine earth fraction: sandy loam, loam, or silt loam
Content of clay: 12 to 25 percent
Content of organic matter: 2 to 4 percent
Reaction: slightly alkaline or moderately alkaline
Content of rock fragments: 0 to 30 percent 2 to 75 millimeter gravel and 0 to 10 percent, 75 to 250 millimeter cobbles
Bt horizons:
Hue: 10YR dry and moist
Value: 5 to 7 dry and 3 to 5 moist
Chroma: 3 or 4 dry and moist
Texture of the fine earth fraction: sandy loam, loam, or silt loam
Content of clay: 12 to 40 percent
Content of organic matter: 1 to 3 percent
Reaction: slightly alkaline or moderately alkaline
Content of rock fragments: 0 to 30 percent 2 to 75 millimeter gravel and 0 to 10 percent 75 to 250 millimeter cobbles
Btk horizons:
Hue: 10YR or 7.5YR dry and moist
Value: 5 to 7 dry and 3 to 5 moist
Chroma: 3 or 4 dry and moist
Texture of the fine earth fraction: sandy loam, loam, or silt loam
Content of clay: 20 to 40 percent
Content of organic matter: 0.1 to 1 percent
Reaction: slightly alkaline or moderately alkaline
Content of rock fragments: 0 to 30 percent 2 to 75 millimeter gravel and 0 to 10 percent 75 to 250 millimeter cobbles
COMPETING SERIES: These are the
Bohna,
Chualar,
Chuloak,
Feethill,
Flaskan,
Franciscan,
Nauti,
Pinto,
Shimmon,
Soper and
Tajea series. Bohna soils have neutral to slightly acid reaction throughout and are 102 to 185 centimeters (40 to 73 inches) deep to a paralithic contact. Chualar soils have no carbonates in the A or B horizons; have 25 to 40 percent coarse or very coarse angular sand in the A and B horizons and have a 2C horizon of gravelly coarse sand, loamy sand, sandy loam or sandy clay loam. Chuloak (MLRA 17) soils have mottles in the lower B or C horizons, lack carbonates and have a C horizon of fine sandy loam or loamy coarse sand. Feethill (MLRA 18), Franciscan (MLRA 15), Nauti (MLRA 20), Shimmon (MLRA 15), Soper (MLRA 15), and Tajea (MLRA 15) soils are moderately deep to bedrock. Flaskan soils (MLRA 14) formed in alluvium from mixed rock sources, occur on alluvial fans and are slightly acid to neutral throughout. Pinto soils have reaction of medium acid to neutral in the solum and a medium acid to strongly acid reaction in the C horizon.
GEOGRAPHIC SETTING: The Geghus soils are on hillslopes and mountain slopes. Slope is 9 to 75 percent. The Geghus soils formed in residuum derived from calcareous shale, sandstone, and/or conglomerate. Elevations are 412 to 1,659 meters (1,352 to 5,440 feet). The climate is semiarid with hot dry summers and cool moist winters. Mean annual precipitation is 203 to 508 millimeters (8 to 20 inches). The mean annual temperature is 14 to 18 degrees C. (57 to 64 degrees F.). Mean July temperature is about 26 degrees C. (79 degrees F.), and mean January temperature is about 6 degrees C. (43 degrees F.). Frost-free season ranges from 150 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Dibble,
Friant, Selby, and Tecuya soils. Dibble soils are moderately deep to a paralithic contact, have a fine particle-size class, and a smectitic mineralogy class. Friant soils are shallow to a lithic contact and have a loamy particle-size class. Selby soils are moderately deep to a lithic contact and have a loamy-skeletal particle-size class. Tecuya soils are on summits and shoulder slopes, have a loamy-skeletal particle-size class, and lack an argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; rapid or very rapid 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 of Southern California. The series is not extensive. MLRA is 15.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Kern County, California, 1991. The name is from nearby Geghus Ridge.
REMARKS: Diagnostic horizons and features recognized in this profile include:
Mollic Epipedon - 0 to 38 centimeters (0 to 15 inches) (A, Bt1, Bt2).
Argillic Horizon - 38 to 137 centimeters (15 to 54 inches).
National Cooperative Soil Survey
U.S.A.