LOCATION WESTGUARD CA

Established Series
Rev. ET-MAV
07/2016

WESTGUARD SERIES

The Westguard series consists of very deep, moderately well drained soils formed in alluvium from mixed sources. Westguard soils are on stream terraces and have slopes of 0 to 2 percent. The mean annual precipitation is about 130 mm and the mean annual temperature is about 15 degrees C.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Durinodic Haplargids

TYPICAL PEDON: Westguard sand, on a one percent slope under black greasewood and shadscale at an elevation of 1,209 meters. (When described on June 11, 1987, the soil was dry to 69 cm and moist below; Colors are for dry soil unless otherwise stated.

A1--0 to 5 cm; light gray (2.5Y 7/2) sand, light brownish gray (2.5Y 6/2) moist; single grain; loose, nonsticky and nonplastic; common very fine and fine and few medium roots; many fine interstitial pores; neutral (pH 7.2); gradual smooth boundary.

A2--5 to 38 cm; light gray (2.5Y 7/2) sand, light brownish gray (2.5Y 6/2) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine and few medium roots; few very fine interstitial pores; neutral (pH 7.2); clear wavy boundary. (Combined thickness of the A horizon is 20 to 48 cm)

Btqkn--38 to 51 cm; light olive gray (5Y 6/2) sandy loam, olive (5Y 4/4) moist; weak medium angular blocky structure parting to weak fine subangular blocky; hard, friable, slightly sticky and slightly plastic; few very fine through medium roots; few very fine tubular pores; few faint clay films bridging mineral grains, in pores and on faces of peds; 5 percent durinodes 12 to 25 mm in diameter; violently effervescent, carbonates segregated as common medium irregular soft masses; very strongly alkaline (pH 9.4); abrupt wavy boundary. (10 to 20 cm thick)

Bkn--51 to 69 cm; light gray (5Y 7/1) sandy loam, pale olive (5Y 6/3) moist; weak fine and medium subangular blocky structure; hard friable, slightly sticky and slightly plastic; few very fine through medium roots; few very fine interstitial pores; violently effervescent, carbonates segregated as common medium irregular shaped soft masses; very strongly alkaline (pH 9.4); abrupt wavy boundary. (13 to 25 cm thick)

2Btqk--69 to 89 cm; light gray (5Y 7/1) silt loam, pale olive (5Y 6/3) moist; moderate thin to thick platy structure; very hard, firm, nonsticky and nonplastic; few very fine through medium roots; few fine tubular pores; few faint clay films on faces of peds, weak continuous silica cementation; violently effervescent, carbonates segregated as few fine irregular soft masses; very strongly alkaline (pH 9.4); clear wavy boundary. (15 to 30 cm thick)

2Cq--89 to 152 cm; light olive gray (5Y 6/2) loam, olive gray (5Y 4/2) moist; common fine and medium angular blocky structure; hard, friable, nonsticky and nonplastic; few fine and medium tubular pores; common thin coatings of silica lining root channels; few medium prominent yellowish brown (10YR 5/6) masses of iron accumulations lining pores and surrounding roots; common fine prominent very dark brown maganeese oxide stains on faces of peds and in root channels; very strongly alkaline (pH 9.4).

TYPE LOCATION: Inyo County, California; about 4.5 miles north west of Big Pine; 1,700 feet south and 1,400 feet east of the northwest corner of Sec 23, T. 8 S., R. 33 E.; USGS Big Pine 7.5 minute topographic quadrangle; latitude 37 degrees 14 minutes 28 seconds N and longitude 118 degrees 19 minutes 34 seconds W; WGS84 Decimal Degrees 37.24111 latitude, 118.326111 longitude.

RANGE IN CHARACTERISTICS: The mean annual soil temperature is 15 to 17.8 degrees C. The soil temperature is below 8.3 degrees C. from about December 1 to March 1, and is below 5 degrees C. from about January 1 to February 1. The soil between the depths of 38 and 61 cm is dry throughout for 200 to 225 days from about May 15 to December 15. It is moist throughout for 65 to 80 days from about January 15 to April 1 and is moist in some or all parts for 70 to 85 consecutive days from about March 1 to May 15 when the soil is above 8.3 degrees C.

The A horizon color is 2.5Y 6/2, 7/2; 10YR 5/2, 6/2 or 6/3. Moist color is 2.5Y 4/2, 5/2, 6/2; 10YR 3/2, 4/2 or 4/3. Textures are sand or loamy sand averaging 2 to 12 percent clay. It is noneffervescent or slightly effervescent. Rock fragment content ranges from 0 to 5 percent. Reaction is neutral to moderately alkaline.

The Btqkn horizon color is 2.5Y 7/2, 6/2; 5Y 6/2, 7/1 or 7/2. Moist color is 2.5Y 4/2, 5/2, 5/4, 6/2; 5Y 4/4, 5/3, 5/4 or 6/3. Textures are loam, or sandy loam averaging 12 to 18 percent clay. It is violently effervescent with medium soft segregated masses of carbonates. Rock fragment ranges from 0 to 5 percent. Reaction is moderately or very strongly alkaline.

The Bkn horizon color is 2.5Y 6/2, 7/2; 5Y 7/1 or 7/2. Moist color is 2.5Y 4/2, 5/2; 5Y 4/3, 5/4, 6/2 or 6/3. Textures are sandy loam or loamy sand averaging 8 to 12 percent clay. Rock fragment content ranges from 0 to 10 percent. Reaction is moderately or very strongly alkaline.

The 2Btqk color is 5Y 7/1 or 7/2. Moist colors is 5Y 5/2, 5/3, 5/4, 6/2, or 6/3. Textures are silt loam, loam, or sandy loam averaging 8 to 12 percent clay. It contains 0 to 10 percent rock fragments. Reaction is moderately or very strongly alkaline.

The 2Cq horizon color is 2.5Y 7/2; 5Y 6/2, 7/1, 7/2 or 8/1. Moist color is 2.5Y 5/2; 5Y 4/2, 4/3, 5/2, 5/3 or 6/2. Textures are sand, loamy sand, sandy loam or loam averaging 8 to 12 percent clay. Stratified phases are recognized with textures of stratified sandy loam and clay loam.

COMPETING SERIES: There are no other series in this family.

GEOGRAPHIC SETTING: Westguard soils are on stream terraces. Slopes are 0 to 2 percent. The soils formed in alluvium from mixed sources. Elevations are 1,160 to 1,250 meters. The climate is arid with hot dry summers and cool moist winters. The mean annual precipitation is 100 to 150 mm. The mean annual temperature is 13.9 to 16.1 degrees C. Mean July temperature is about 80 degrees F., and mean January temperature is about 4.4 degrees C. The frost-free season is 140 to 180 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Inyo (T), and Poleta (T) soils. Inyo soils do not have an argillic horizon and are somewhat excessively drained. Poleta soils have an indurated duripan. These soils are on stream terraces.

DRAINAGE AND PERMEABILITY: Moderately well drained; slow runoff; moderate or moderately slow permeability due to high SAR. In some areas the substratum has rapid permeability.

USE AND VEGETATION: Westguard soils are used for rangeland and wildlife habitat. Vegetation is shadscale, black greasewood, alkali sacaton and inland saltgrass.

DISTRIBUTION AND EXTENT: Owens Valley of east central California. The series is not extensive in MLRA 29.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES PROPOSED: Benton-Owens Valley Area, Inyo County, California, 1988. The name is taken from a nearby mountain pass.

REMARKS: Diagnostic horizon and features recognized in this pedon are:

1. Ochric epipedon - 0 to 38 cm (A1, A2)

2. Argillic horizon - 38 to 51 cm (Btkqn)

3. Duric Horizon - 69 to 89 cm (Btqk)

4. Moisture regime - Aridic

4.1 The moisture control section is dry throughout from May 15 to December 15. It is moist in some or all parts from March 1 to May 15 when the soil is above 8.3 degrees C.

4.2 The soil temperature exceeds 5 degrees C. from February 1 to January 1 (334 days). Within this time period, the moisture control section is dry from May 15 to December 15 (214 days).

4.3 The soil temperature exceeds 8.3 degrees C. from March 1 to December 1 (275 days). Within this time period, the moisture control section is dry from May 15 to December 1 (199 days).

National Cooperative Soil Survey
U.S.A.