LOCATION WEEDPATCH CATentative Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Typic Haplocalcids
TYPICAL PEDON: Weedpatch clay loam, saline-sodic, 0 to 1 percent slopes, in a fallow field, at an elevation of 320 feet. (Colors are for dry soil unless otherwise stated. When described on September 9, 1988 the soil was dry to 24 inches and slightly moist below.)
Ap--0 to 8 inches; pale brown (10YR 6/3) clay loam, dark yellowish brown (10YR 3/4) moist; very coarse clods; hard, friable, sticky and plastic; few very fine and fine roots; common very fine tubular pores; violently effervescent, carbonates disseminated; calcium carbonate equivalent 8.5 percent; moderately alkaline (pH 8.4); clear smooth boundary. (6 to 10 inches thick)
Ak--8 to 18 inches; pale brown (10YR 6/3) clay loam, dark yellowish brown (10YR 3/4) moist; weak coarse subangular blocky structure; hard, friable, sticky and plastic; few very fine and fine roots; few very fine tubular pores; violently effervescent, carbonates disseminated and segregated as few fine soft masses; calcium carbonate equivalent 13 percent; moderately alkaline (pH 8.4); abrupt smooth boundary. (0 to 12 inches thick)
2Bkn1--18 to 24 inches; pale yellow (2.5Y 7/4) clay loam, olive brown (2.5Y 4/4) moist; weak very fine columnar structure parting to strong fine angular blocky; hard, firm, sticky and very plastic; few very fine roots; common very fine and few fine, medium, and coarse tubular pores; many pressure faces and few thin dark organic stains on faces of peds; violently effervescent, carbonates disseminated and segregated as common fine and medium soft masses and as fine and medium concretions, 15 percent by volume; calcium carbonate equivalent 17 percent; strongly alkaline (pH 8.6); abrupt smooth boundary.
2Bkn2--24 to 42 inches; light gray (2.5Y 7/2) clay loam, dark grayish brown (2.5Y 4/2) moist; weak very fine columnar structure parting to strong fine and medium angular blocky; hard, firm, sticky and very plastic; few very fine and fine roots; common very fine, fine and medium and few coarse tubular pores; many pressure faces and few thin dark organic stains on faces of peds; violently effervescent, carbonates disseminated and segregated as many fine, medium and large soft masses and as fine, medium and large concretions, 20 percent by volume; calcium carbonate equivalent 30 percent; strongly alkaline (pH 8.8); abrupt smooth boundary.
2Bkn3--42 to 47 inches; pale yellow (5Y 7/3) clay loam, olive (5Y 4/3) moist; weak very fine prismatic structure parting to strong very fine angular blocky; hard, firm, sticky and very plastic; few very fine and fine roots; common very fine and fine and few medium tubular pores; many pressure faces and few thin dark organic stains on faces of peds; violently effervescent, carbonates disseminated and segregated as many fine, medium and large soft masses and as fine, medium and large concretions, 35 percent by volume; calcium carbonate equivalent 48 percent; strongly alkaline (pH 8.9); abrupt smooth boundary.
2Bkn4--47 to 59 inches; pale yellow (5Y 7/3) clay loam, olive (5Y 5/3) moist; common brown (7.5YR 5/4) medium and large prominent mottles, dark brown (7.5YR 4/4) moist; moderate very fine subangular blocky structure; hard, firm, sticky and very plastic; few very fine and fine roots; common very fine, fine and medium and few coarse tubular pores; many pressure faces and few thin dark organic stains on faces of peds; violently effervescent, carbonates disseminated and segregated as common fine, and medium soft masses and as many fine and medium concretions, 25 percent by volume; calcium carbonate equivalent 32 percent; strongly alkaline (pH 8.6); clear wavy boundary. (combined thickness of the 2Bkn horizons is 30 to 60 inches)
2C--59 to 64 inches; pale olive (5Y 6/3) clay loam, olive (5Y 4/3) moist; common dark brown (7.5YR 4/4) moist, medium and large prominent mottles; moderate medium subangular blocky structure; hard, friable, sticky and very plastic; common very fine and few fine tubular pores; calcium carbonate equivalent is less than 5 percent; moderately alkaline (pH 8.4)
TYPE LOCATION: Kern County, California; about 10 miles south of Bakersfield; 2185 feet north and 1240 feet east of the southwest corner of Sec. 21, T. 31 S., R. 28 E., MDB&M; 35 degrees, 12 minutes, 52 seconds north latitude and 118 degrees, 58 minutes, 49 seconds west longitude; Weed Patch quadrangle.
RANGE IN CHARACTERISTICS:
Soil Temperature: mean annual - 64 to 72 degrees F. never below 47 degrees F.
Soil Moisture: dry throughout from early March to early January for about 275 to 300 day.
Particle size control section:
Calcium carbonate equivalent: averages 15 to 40 percent
Electrical conductivity: less than 2 mmhos/cm
A horizon:
Value: 3 or 4 moist
Chroma: 5 or 6 dry
Clay content: 28 to 35 percent
Effervescence: strongly or violently
Calcium carbonate equivalent: 5 to 15 percent
Organic matter: less than 1 percent to a depth of 10 inches
Electrical conductivity: 2 to 8 mmhos/cm
2Bkn horizon:
Hue: 10YR, 2.5Y or 5Y
Value: 6 or 7 dry, 4 or 5 moist
Chroma: 2, 3 or 4 dry or moist
Texture: clay loam, silty clay loam or loam with 20 to 35 percent clay and averages less than 35 percent
Calcium carbonate equivalent: 15 to 40 percent, any one horizon may range up to 50 percent.
Sodium adsorption ratio: 3 to 8
2C horizon:
Texture: loam or clay loam with an average of 20 to 35 percent clay Calcium carbonate equivalent: 0 to 10 percent
COMPETING SERIES: These are the Bridge, Deltajo, Laverkin, Sotim, Sunrise, and Turney series. Bridge, Deltajo, Sotim, and Turney soils have moisture control sections moist 40 to 60 days during the summer months. Laverkin soils have soil temperatures below 47 degrees F. in January and February. Sunrise soils are moderately deep.
GEOGRAPHIC SETTING: Weedpatch soils are on relict basin floors. Slopes are 0 to 1 percent. The soils formed in alluvium derived dominantly from granitic rock. Elevations are 280 to 375 feet. The climate is arid with hot dry summers and cool, slightly moist winters. The mean annual precipitation is 5 to 6 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, and Wasco soils. Bakersfield and Milagro soils are on adjacent flood plains and have an irregular decrease in organic matter. Cajon soils are on adjacent alluvial fans and flood plains and are sandy. Kimberlina and Wasco soils are on adjacent low alluvial fans and are coarse-loamy. Panoche soils are on adjacent low alluvial fans and do not have a calcic horizon.
DRAINAGE AND PERMEABILITY: Well drained; very slow to slow runoff; slow permeability. These soils are subject to rare flooding but are protected by dams and/or levees.
USE AND VEGETATION: Weedpatch soils are used for irrigated crops and homesite development. The native vegetation is annual grasses and forbs.
DISTRIBUTION AND EXTENT: Southern San Joaquin Valley of California. The series is not extensive in MLRA 17.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Kern County, California, 1989. The name is from the nearby town of Weed Patch.
REMARKS: Reference samples from this soil (S89CA-029-003 (1-3)) were analyzed by the National Soil Survey Laboratory.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon -- the zone from the surface to a depth of 18 inches (Ap and Ak horizons).
Calcic horizon -- The zone from 8 to 59 inches (2Bkn1, 2Bkn2, 2Bkn3, and 2Bkn4 horizons).
Mineralogy -- mixed; the calcium carbonate content (plus gypsum) is less than 40 percent by weight.
Particle size control section -- the zone from 10 to 40 inches