LOCATION OLDRIVER CATentative Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Torrifluventic Haploxerolls
TYPICAL PEDON: Oldriver loam, partially drained, sodic, in a recently plowed rice field, at an elevation of 295 feet. (When described on January 25, 1990, the soil was moist from 0 to 9 inches, slightly moist from 9 to 22 inches, moist from 22 to 63 inches, and approaching saturation at 63 inches; Colors are for dry soil unless otherwise stated).
Ap--0 to 11 inches; grayish brown (2.5Y 5/2) loam, very dark grayish brown (2.5Y 3/2) moist; clods parting to moderate fine and medium granular structure; slightly hard, friable, sticky and plastic; common very fine and few fine and medium roots; common very fine interstitial pores; mildly alkaline (pH 7.8); abrupt smooth boundary. (10 to 19 inches thick)
C1--11 to 16 inches; light brownish gray (2.5Y 6/2) fine sandy loam, dark grayish brown (2.5Y 4/2) moist; common dark yellowish brown (10YR 4/6) fine prominent mottles, dark yellowish brown (10YR 3/6) moist; massive; slightly hard, friable, nonsticky and nonplastic; few very fine and fine roots; few very fine tubular pores; strongly alkaline (pH 8.7); abrupt smooth boundary. (0 to 10 inches thick)
C2--16 to 22 inches; light brownish gray (2.5Y 6/2) and dark grayish brown (2.5Y 4/2) finely stratified (0.5 to 2 mm) with a mixed texture of silt loam and very fine sandy loam, dark grayish brown (2.5Y 4/2) and very dark grayish brown (2.5Y 3/2) moist; common dark yellowish brown (10YR 4/6) fine prominent mottles, dark yellowish brown (10YR 3/6) moist; massive with strong very fine and fine platy rock structure; hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; few very fine tubular pores; slightly effervescent disseminated carbonates; moderately alkaline (pH 8.2); abrupt smooth boundary. (0 to 18 inches thick)
C3--22 to 30 inches; light olive gray (5Y 6/2) clay, dark olive gray (5Y 3/2) moist; common light olive brown (2.5Y 5/4) fine and medium prominent mottles, dark grayish brown (2.5Y 4/2) distinct and olive brown (2.5Y 4/4) prominent moist; moderate medium subangular blocky structure; very hard, firm, sticky and very plastic; few very fine and fine roots; common very fine tubular pores; strongly alkaline (pH 8.6); abrupt smooth boundary. (3 to 15 inches thick)
C4--30 to 39 inches; light brownish gray (2.5Y 6/2) fine sandy loam, dark grayish brown (2.5Y 4/2) moist; common yellowish brown (10YR 5/4) and pale olive (5Y 6/3) medium prominent and distinct mottles, dark grayish brown (2.5Y 4/2) and olive (5Y 4/3) moist; massive; hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine tubular pores; strongly effervescent disseminated carbonates; moderately alkaline (pH 8.2); clear smooth boundary. (0 to 12 inches thick)
C5--39 to 49 inches; light brownish gray (2.5Y 6/2) fine sandy loam, dark grayish brown (2.5Y 4/2) moist; many yellowish brown (10YR 5/4) medium and coarse prominent mottles, dark yellowish brown (10YR 4/4) moist; many very dark gray (5Y 3/1) and dark olive gray (5Y 3/2) fine prominent mottles moist that disappear when dry; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine roots; common very fine tubular pores; strongly effervescent disseminated carbonates; moderately alkaline (pH 8.2); abrupt smooth boundary. (0 to 15 inches thick)
C6--49 to 63 inches; light yellowish brown (2.5Y 6/4) silty clay with a few very thin plates (less than 1mm) of micaceous sand, olive brown (2.5Y 4/4) moist; common yellowish brown (10YR 5/4) medium distinct mottles, dark yellowish brown (10YR 4/4) moist; common olive gray (5Y 4/2) and few very dark gray (5Y 3/1) fine and medium prominent mottles moist that disappear when dry; massive; very hard, firm, very sticky and very plastic; common very fine tubular pores; strongly effervescent disseminated carbonates; moderately alkaline (pH 8.0); abrupt smooth boundary.
TYPE LOCATION: Kern County, California; about 14 miles south of downtown Bakersfield; 1 mile east of Union Avenue and 2.5 miles south of Bear Mountain Boulevard; 2,280 feet north and 250 feet east of the southwest corner of Sec. 4, T. 32 S., R. 28 E., MDB&M; 35 degrees, 10 minutes, 15 seconds north latitude and 118 degrees, 59 minutes, 2 seconds west longitude; Weed Patch 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 mid April to late December and is never moist more than 90 consecutive days.
Particle size control section:
clay content: ranges from 8 to 50 percent but averages 18 to 35 percent.
Electrical conductivity: 0 to 4 mmhos/cm throughout
Ap horizon
Hue: 10YR or 2.5Y
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 1, 2, or 3 dry and moist
clay content: 18 to 27 percent
Organic matter: 1 to 4 percent
Effervescence: noneffervescent or slightly
Sodium absorption ratio: 2 to 15
Reaction: mildly alkaline or moderately alkaline
C horizons
Hue: 10YR, 2.5Y, or 5Y
Value: 4, 5, or 6 dry, 3 or 4 moist
Chroma: 1, 2, 3, or 4 dry and moist
Texture: stratified, ranging from loamy sand to silty clay; individual pedons typically have coarse-loamy, fine-loamy, and fine strata; strata are discontinuous and their sequence varies greatly within short distances.
Organic matter: 0.05 to 2.0 percent; it decreases irregularly with depth
Effervescence: noneffervescent to strongly effervescent
Sodium absorption ratio: 2 to 25
Reaction: moderately alkaline or strongly alkaline
COMPETING SERIES: There are no other soils in this family.
GEOGRAPHIC SETTING: Oldriver soils are on floodplains. Slopes are 0 to 1 percent. The soils formed in stream alluvium derived dominantly from granitic rock. Elevations are 280 to 500 feet. The climate is arid with hot dry summers and cool, somewhat moist winters. The mean annual precipitation is 5 to 7 inches. The mean annual temperature is 62 to 67 degrees F. Mean July temperature is about 85 degrees F., and mean January temperature is about 47 degrees F. The frost-free season is 250 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bakersfield (T), Cajon, Kimberlina, Milagro (T), Panoche, Vineland (T), Wasco, and Weedpatch (T) soils. Bakersfield and Milagro soils are on similar landforms and are coarse-loamy. Cajon and Vineland soils are on similar landforms and are sandy. Kimberlina and Wasco soils are on adjacent low alluvial fans, are coarse-loamy and have a regular decrease in organic matter. Panoche soils are on adjacent low alluvial fans and have a regular decrease in organic matter. Weedpatch soils are on adjacent relic basin floors and have a calcic horizon.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow runoff; slow permeability. Oldriver soils have been artificially drained and protected from flooding in most areas by dams, levees, and diversions. The partially drained phase of this soil has a water table at a depth of 4 to 6 feet from March through August as a result of irrigation and below 6 feet during the rest of the year.
USE AND VEGETATION: Used primarily for irrigated crops such as cotton, rice, alfalfa, dry beans, corn, barley, and wheat. Some areas are used for homesites and pasture. Native vegetation is dominantly annual grasses and forbs with scattered willow and sycamore trees.
DISTRIBUTION AND EXTENT: Southern San Joaquin Valley of California. The series is not extensive. MLRA is 17.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Kern County, California, 1990. The name is from the town of Old River.
REMARKS: The type location was described during a period of drought when there had been less than one inch of precipitation during the preceding 6 months. Diagnostic horizons and features recognized in the profile are:
Mollic epipedon -- the zone from the soil surface to 11 inches (Ap)
Torrifluventic subgroup -- Has a well defined irregular decrease in organic carbon with depth based on modified Walkley-Black method and visual observation. The moisture regime is aridic bordering on xeric.
Particle size control section -- The zone from 10 to 40 inches