LOCATION TENNCO CATentative Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Typic Natrargids
TYPICAL PEDON: Tennco fine sandy loam, 0 to 1 percent slopes, under salt desert shrubs and annual grasses and forbs at an elevation of 315 feet. (Colors are for dry soil unless otherwise stated. When described on December 12, 1988 the soil was dry throughout)
A--0 to 1 inch; light brownish gray (2.5Y 6/2) fine sandy loam, dark grayish brown (2.5Y 4/2) moist; weak thick platy structure parting to moderate fine subangular blocky; soft, very friable, nonsticky and nonplastic; many very fine roots; common very fine tubular and interstitial pores; neutral (pH 7.2); abrupt smooth boundary. (1 to 10 inches thick)
Enz--1 to 5 inches; pale yellow (2.5Y 7/4) sandy loam, light olive brown (2.5Y 5/4) moist; moderate very coarse columnar structure; soft, very friable, nonsticky and nonplastic; common very fine roots; many very fine and few fine vesicular pores; slightly effervescent, carbonates disseminated; very strongly alkaline (pH 9.2); abrupt smooth boundary. (0 to 5 inches thick)
Btnz--5 to 13 inches; light gray (2.5Y 7/2) sandy loam, olive brown (2.5Y 4/4) moist; strong very coarse prismatic structure; hard, friable, sticky and slightly plastic; common very fine and few fine and medium roots; common very fine tubular and interstitial and few fine and medium tubular pores; few thin clay films in bridges between mineral grains; slightly effervescent, carbonates disseminated; very strongly alkaline (pH 10.2); abrupt smooth boundary. (8 to 24 inches thick)
BCnz--13 to 18 inches; light gray (2.5Y 7/2) sandy loam, olive brown (2.5Y 4/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine tubular and interstitial and few fine and medium tubular pores; slightly effervescent, carbonates disseminated; very strongly alkaline (pH 10.2); abrupt smooth boundary. (0 to 5 inches thick)
2Cnz1--18 to 25 inches; light gray (2.5Y 7/2) silt loam, olive brown (2.5Y 4/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and few fine and medium tubular pores; slightly effervescent, carbonates disseminated; very strongly alkaline (pH 10.0); clear smooth boundary.
2Cnz2--25 to 45 inches; light gray (2.5Y 7/2) loam, olive brown (2.5Y 4/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine, common fine and few medium tubular pores; slightly effervescent, carbonates disseminated; very strongly alkaline (pH 10.0); clear smooth boundary. (Combined thickness of the 2C1 and 2C2 horizons is 15 to 35 inches thick)
2Cknz--45 to 60 inches; pale yellow (2.5Y 7/4) loam, olive brown (2.5Y 4/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and few fine tubular pores; very slightly effervescent, carbonates disseminated and segregated as few fine soft masses; very strongly alkaline (pH 10.2).
TYPE LOCATION: Kern County, California; about 6 miles east of Old River; 450 feet east and 240 feet south of the northwest corner of Sec. 5, T. 31 S., R. 26 E., MDB&M; 35 degrees, 16 minutes, 24 seconds north latitude and 119 degrees, 12 minutes, 22 seconds west longitude; Stevens quadrangle.
RANGE IN CHARACTERISTICS:
Soil temperature - Average annual: 62 to 67 degrees F and the soil temperature is never below 47 degrees F.
Soil moisture - dry throughout from early April to late December and is never moist more than 90 consecutive days.
A horizon
Hue: 10YR or 2.5Y
Value: 5, 6, or 7 dry, 3, 4, or 5 moist
Percent clay: 5 to 14
Effervescence: noneffervescent or slightly
Electrical conductivity: 0 to 4 mmhos/cm
Sodium absorption ratio: 3 to 13
Reaction: neutral to strongly alkaline
E horizon
Chroma: 2 or 4 dry and moist
Texture: sandy loam or fine sandy loam
Percent clay: 3 to 14
Effervescence: noneffervescent or slightly
Electrical conductivity: 4 to 16 mmhos/cm
Sodium absorption ratio: 10 to 45
Reaction: strongly alkaline or very strongly alkaline
Other: this horizon is sometimes destroyed by plowing
Btn horizon
Value: 6 or 7 dry and 4 or 5 moist
Chroma: 2 or 4 dry and moist
Texture: sandy loam or fine sandy loam
Percent clay: 12 to 18
Effervescence: noneffervescent or slightly
Electrical conductivity: 12 to 25 mmhos/cm
Sodium absorption ratio: 13 to 70
C horizons
Hue: 10YR or 2.5Y
Value: 6 or 7 dry and 4 or 5 moist
Chroma: 2, 3, or 4 dry and moist
Texture: stratified sandy loam, fine sandy loam, loam, or silt loam Percent clay: 6 to 15
Effervescence: slightly or strongly
Electrical conductivity: 16 to 35 mmhos/cm
Sodium absorption ratio: 30 to 200
COMPETING SERIES: These are the Halloran, Mazourka (T), and Mobl (T) series. Halloran soils have 5YR or 7.5YR Btk horizons and gypsum in the lower part of the control section. Mazourka and Mobl soils have soil temperatures below 47 degrees F. in January and February.
GEOGRAPHIC SETTING: Tennco soils are on relict basin floors. Slopes are 0 to 1 percent. The soils formed in alluvium derived dominantly from granitic rock. Elevations are 290 to 330 feet. The climate is arid with hot dry summers and cool, somewhat moist winters. The mean annual precipitation is 5 to 6 inches. The mean annual temperature is 62 to 67 degrees F. The mean January temperature is about 47 degrees F., and the mean July temperature is about 85 degrees F. Frost-free season is 250 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Kimberlina and Garces soils. The Kimberlina soils are on adjacent low lying alluvial fans and do not have a natric horizon. The Garces soils are on similar landforms and are fine-loamy.
DRAINAGE AND PERMEABILITY: Well drained; very slow to slow runoff; moderately slow permeability. The soils are subject to rare flooding but are protected by dams and levees.
USE AND VEGETATION: Tennco soils are used for native pasture, oilfields, and wildlife habitat. Reclaimed areas are used for irrigated cropland. Vegetation is scattered allscale saltbush and mesquite with annual grasses and forbs.
DISTRIBUTION AND EXTENT: The southern end of the San Joaquin Valley of California. The soil is not extensive. MLRA is 17.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Kern County, California, 1989. The name is coined.
REMARKS: The electrical conductivity and sodium absorption ratio values mentioned in the range in characteristics section refer to unreclaimed areas of this soil. Values in reclaimed areas will be lower. Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon -- The zone from the soil surface to 1 inch (A).
Natric horizon - The zone from 5 to 13 inches (Btn).