LOCATION WESTHAVEN CAEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, thermic Fluventic Haplocambids
TYPICAL PEDON: Westhaven loam, on a southeast-facing slope of 1 percent under an almond orchard at 278 feet elevation. (Colors are for dry soil unless otherwise stated. When described 11/6/78 the soil was dry from 0 to 29 inches and slightly moist below.)
Ap--0 to 7 inches; light brownish gray (2.5Y 6/2) loam, dark grayish brown (2.5Y 4/2) moist; moderate coarse subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; common very fine and few fine roots; common very fine tubular and many very fine interstitial pores; slightly effervescent, carbonates disseminated; moderately alkaline (pH 8.0); abrupt smooth boundary. (7 to 14 inches thick)
Bw--7 to 19 inches; light brownish gray (2.5Y 6/2) silt loam, dark grayish brown (2.5Y 4/2) moist; weak coarse subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; few very fine, fine and medium roots; common very fine tubular and many very fine interstitial pores; slightly effervescent, carbonates disseminated; moderately alkaline (pH 8.1); clear wavy boundary. (9 to 15 inches thick)
Bk1--19 to 24 inches; light brownish gray (2.5Y 6/2) silty clay loam, with many discontinuous thin strata of silty clay and silt loam, dark grayish brown (2.5Y 4/2) moist; massive; slightly hard, friable, moderately sticky and moderately plastic; few very fine, fine and medium roots; many very fine tubular and interstitial pores; strongly effervescent, carbonates disseminated and segregated as common fine irregularly shaped soft masses; moderately alkaline (pH 8.0); abrupt wavy boundary. (5 to 22 inches thick)
Bk2--24 to 29 inches; light brownish gray (2.5Y 6/2) silt loam, with many discontinuous thin strata of silty clay loam, dark grayish brown (2.5Y 4/2) moist; massive; slightly hard, very friable, moderately sticky and moderately plastic; few fine roots; many very fine tubular and interstitial pores; strongly effervescent, carbonates disseminated and segregated as common fine irregularly shaped soft masses; common fine prominent dark yellowish brown (10YR 3/6) moist relict redoximorphic concentrations of iron; moderately alkaline (pH 8.1); gradual wavy boundary. (5 to 22 inches thick)
C1--29 to 45 inches; light brownish gray (2.5Y 6/2) silt loam, dark grayish brown (2.5Y 4/2) moist; massive; slightly hard; very friable, moderately sticky and moderately plastic; few very fine roots; many very fine tubular and interstitial pores; strongly effervescent, carbonates disseminated; moderately alkaline (pH 8.2); clear wavy boundary. (0 to 16 inches thick)
2C2--45 to 72 inches; light brownish gray (2.5Y 6/2) silty clay dark grayish brown (2.5Y 4/2) moist; massive, hard, friable, moderately sticky and very plastic; few very fine tubular pores; strongly effervescent, carbonates disseminated; moderately alkaline (pH 7.9); abrupt wavy boundary. (0 to 27 inches thick)
3C3--72 to 84 inches; light gray (2.5Y 7/2) loamy sand, dark grayish brown (2.5Y 4/2) moist; massive; loose; many very fine interstitial pores; slightly alkaline (pH 7.8).
TYPE LOCATION: Kings County, California; approximately 2,600 feet south of Nevada Avenue and 250 feet west of 30th Avenue; about 2,600 feet south and 250 feet west of the northeast corner of section 3, T. 21 S., R. 18 E.; MDB&M; Latitude 36 degrees, 07 minutes, 51 seconds north and Longitude 120 degrees, 00 minutes, 16 seconds west; USGS Huron Topographic Quadrangle, NAD 27.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 64 degrees to 67 degrees F. and the soil temperature is always above 47 degrees F. The soil between depths of 4 and 12 inches is dry in all parts from April through December and is not moist in some or all parts for as long as 90 consecutive days. The particle-size control section averages 18 to 35 percent clay. Less than 15 percent of the particles are fine sand or coarser, by weighted average, between depths of 10 to 40 inches. Electrical conductivity is 0 to 4.0 decisiemens per meter, and sodium adsorption ratio is 0 to 12. Calcium carbonate equivalent is 0 to 5 percent. Organic matter decreases irregularly with increasing depth.
The A horizon has color of 10YR 5/3, 5/4, 6/2, 6/3, 6/4, 7/4; 2.5Y 6/2 or 6/4. Moist color is 10YR 3/2, 3/3, 4/3, 4/4; 2.5Y 4/2 or 4/3. Texture is fine sandy loam, sandy loam, silt loam, loam or clay loam. It is noneffervescent to strongly effervescent. Reaction is slightly alkaline or moderately alkaline.
The Bw horizon has color of 10YR 5/3, 5/4, 6/3, 6/4, 7/2; 2.5Y 4/2, 5/2, 5/4, 6/2, 6/4 or 7/4. Moist color is 10YR 4/2, 4/3, 5/2, 5/3; 2.5Y 4/2, 4/3, 4/4, 5/2 or 5/4. Texture is fine sandy loam, silt loam, loam, silty clay loam or clay loam. It is very slightly effervescent to slightly effervescent. Reaction is slightly alkaline or moderately alkaline.
The Bk horizon has color of 10YR 5/3, 5/4, 6/3, 6/4, 7/2: 2.5Y 4/2, 5/2, 5/4, 6/2, 6/4, 7/2 or 7/4. Moist color is 10YR 4/2, 4/3, 5/2, 5/3; 2.5Y 4/2, 4/4, 5/2 or 5/4. It is stratified loamy sand, loamy fine sand, fine sandy loam, very fine sandy loam, silt loam, loam, sandy clay loam, silty clay loam and clay loam. Texture is slightly effervescent to strongly effervescent. Carbonates are disseminated and segregated with common threads or soft masses.
The C horizon, when present, has color of 10YR 5/3, 5/4, 6/3, 6/4, 7/2; 2.5Y 4/2, 5/2, 5/4, 6/2, 6/4, 7/2 or 7/4. Moist color is 10YR 4/2, 4/3, 5/2, 5/3, 6/1; 2.5Y 4/2, 4/4, 5/2 or 5/4. Relict redoximorphic concentrations of iron occur in some pedons below a depth of 20 inches. Texture is loamy sand to clay below a depth of 40 inches. It is noneffervescent to strongly effervescent with disseminated carbonates. Reaction is slightly alkaline or moderately alkaline.
COMPETING SERIES: This is the Tornillo series. Tornillo soils (MLRA 42) are on broad valley floors and are intermittently moist in the summer and have color hue of 7.5YR or 10YR in the A horizon and 5YR to 10YR in the B horizon.
GEOGRAPHIC SETTING: Westhaven soils are on stratified alluvial fans and flood plains at elevations of 200 to 850 feet. They formed in mixed alluvium from sedimentary and/or igneous rocks. Slope is 0 to 5 percent. The climate is arid and has hot, dry summers and cool, somewhat moist winters. The mean annual precipitation is 4 to 8 inches. The mean January temperature is 46 degrees F., mean July temperature is 80 degrees F., and the mean annual temperature is 62 degrees to 65 degrees F. The frost-free season is 240 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Excelsior, Kimberlina, Lethent, Panoche, Twisselman, Wasco, and Westcamp soils. Excelsior, Kimberlina, and Wasco soils have a coarse-loamy particle-size control section. Kimberlina, Panoche, Twisselman, and Wasco soils have a regular decrease in organic carbon with increasing depth. Lethent soils are on fan skirts and basin rims and have a natric horizon. Panoche soils have a fine-loamy particle-size control section. Twisselman soils have a fine particle-size control section. Westcamp soils are on basin rims and have an aquic moisture regime. Excelsior, Kimberlina, Wasco, Panoche and Twisselman are on alluvial fans.
DRAINAGE AND PERMEABILITY: Well drained; low runoff; moderately slow permeability. These soils are subject to very rare to occasional flooding in some places, in others they are protected by dams and levees.
USE AND VEGETATION: This soil is used for irrigated cropland to grow wheat, lettuce, cotton, tomatoes, almonds, grapes, and peaches. The natural vegetation was mainly saltbush (Atriplex spp.) and annual grasses and forbs. Some areas are used for building site development.
DISTRIBUTION AND EXTENT: San Joaquin Valley, California. Westhaven series is moderately extensive. MLRA 17.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Kings County, California, 1980.
REMARKS: Fluventic subgroup based on irregular distribution of organic matter in the highly stratified layers between 19 and 84 inches. Distribution of carbonates within the profile has been affected by irrigation. In some pedons, segregated carbonates are present throughout the entire profile below the Bw horizon. These are designated Bk horizons and no C horizon is designated.
The original competing series before taxonomy change were the Glendale (AZ) and Pima (AZ) series. Glendale and Pima soils are intermittently moist in the moisture control section during July, August and September from summer thunderstorms.
Previously mapped as Panoche series in the Soil Survey of Mendota Area, California, Series 1940, No. 18 and Coalinga Area, California, Series 1944, No. 1. The classification of Westhaven series was established as Typic Torrifluvents. This was changed to Fluventic Haplocambids when a cambic horizon was recognized in the Westhaven profile. The presence of a cambic horizon is based on the following characteristics:
1. Soil structure in the cambic horizon (unless moist from irrigation or rainfall or drastically modified by deep ripping)
2. Removal of carbonates from the cambic horizon
3. Accumulation of carbonates below the cambic horizon which supports loss of carbonate from overlying horizons
4. Higher chroma in the cambic horizon in some pedons
5. Most areas of Westhaven soils are irrigated with 2 to 3 feet of water per year applied for crop production. Previous to irrigation only about 7 inches of precipitation coupled with flood water, was available for soil development. Movement of carbonates, fertilizer and salt through the soil profile has created more pronounced cambic horizons because of application of irrigation water. The recognition of a cambic horizon in this soil necessitates the placing of all saline-sodic and saline-alkali phases of Westhaven series into another soil series. These soils would classify as fine-silty, mixed, superactive, thermic Sodic Haplocambids. Many of these soils will be called Posochanet series. Posochanet soils occur on lower position in the landscape (fan skirts) than Westhaven soils (alluvial fans), which are not saline-sodic. Map unit 178 in Kings County should be correlated from Westhaven to Posochanet series.
Major Diagnostic Horizons:
1. Ochric epipedon--0 to 7 inches (Ap)
2. Cambic horizon--7 to 19 inches (Bw)
2.1 Removal of carbonates from the cambic horizon
3. Zone of redistribution--19 to 29 inches (Bk)