LOCATION STANDISH CAEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Xeric Natrargids
TYPICAL PEDON: Standish fine sandy loam, rangeland on a 2 percent SW facing slope under a cover of big sagebrush and greasewood at about 4,200 feet elevation. (When described June 21, 1983, the soil was moist from 7 to 27 inches (adjacent to an irrigated field). Colors are for dry soil unless otherwise noted).
A1--0 to 4 inches; grayish brown (10YR 5/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine roots; many very fine interstitial pores; neutral (pH 7.0); abrupt smooth boundary.
A2--4 to 7 inches; very pale brown (10YR 7/3) coarse sandy loam, brown (10YR 5/3) moist; moderate, medium and coarse angular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine roots; many very fine interstitial pores; moderately alkaline (pH 8.0); abrupt smooth boundary. (The combined thickness of the A horizons is 3 to 8 inches).
2Btn1--7 to 12 inches; very pale brown (10YR 7/4) clay, yellowish brown (10YR 5/4) moist; strong fine prismatic structure; very hard, very firm, very sticky and very plastic; few very fine and fine roots; common very fine tubular pores; continuous thick pale brown (10YR 6/3) clay films, brown (10YR 4/3) moist, on peds and in pores; SAR is 13; strongly alkaline (pH 8.5); clear wavy boundary.
2Btn2--12 to 16 inches; light yellowish brown (10YR 6/4) clay, dark yellowish brown (10YR 4/4) moist; strong fine prismatic structure; very hard, very firm, very sticky and very plastic; few very fine and fine roots; common very fine tubular pores; continuous thick clay films on peds and in pores; SAR is 19; strongly alkaline (pH 8.5); clear wavy boundary.
2Btnk--16 to 27 inches; light yellowish brown (10YR 6/4) sandy clay loam, dark yellowish brown (10YR 4/4) moist; moderate coarse angular blocky structure; hard, friable, sticky and plastic; few very fine, fine and medium roots; common very fine tubular and interstitial pores; common moderately thick clay films on peds and in pores; violently effervescent, lime segregated in common fine soft filaments; strongly alkaline (pH 8.5); clear wavy boundary. (The combined thickness of the Btn horizons is 10 to 27 inches).
3Bkn1--27 to 39 inches; light yellowish brown (2.5Y 6/4) sandy loam, olive brown (2.5Y 4/4) moist; weak coarse angular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few very fine, fine, medium and coarse roots; many very fine interstitial pores; strongly effervescent, lime segregated in common fine soft filaments; strongly alkaline (pH 8.5); clear wavy boundary.
3Bkn2--39 to 53 inches; light yellowish brown (2.5Y 6/4) and light brownish gray (2.5Y 6/2) coarse sandy loam, olive brown (2.5Y 4/4) and dark grayish brown (2.5Y 4/2) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine interstitial pores; strongly effervescent, lime segregated in common fine soft filaments; strongly alkaline (pH 8.5) abrupt wavy boundary.
3Bkn3--53 to 65 inches; light yellowish brown (2.5Y 6/4) loamy sand, olive brown (2.5Y 4/4) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine interstitial pores; strongly effervescent, lime segregated in common fine soft filaments; few relic mottles; strongly alkaline (pH 8.5). (The combined thickness of the Bkn horizons is 35 to 42 inches)
TYPE LOCATION: Lassen County, California; about 7.1 miles N of the town of Doyle; 2.9 miles S on HWY 395 from its junction with County Road A25 and 0.7 mile N of HWY 395; 400 feet S and 2,500 feet E of the NW corner of Sec. 17, T. 26 N., R. 16 E.
RANGE IN CHARACTERISTICS: The combined thickness of the A and 2Btn horizons is 20 to 30 inches. Depth to carbonates ranges from 10 to 28 inches. The mean annual soil temperature varies from 53 to 56 degrees F. The mean summer soil temperature varies from 69 to 71 degrees F. and the mean winter soil temperature varies from 38 to 41 degrees F. The soil moisture control section (9 to 20 inches) is dry throughout from June 1 to November 15 (168 days) and is moist throughout from December 1 to April 15. The soil temperature exceeds 41 degrees F. from March 1 to December 15 (290 days) and exceeds 47 degrees F. from April 15 to November 15 (214 days).
The A horizon dry color is 10YR 5/2, 5/3, 6/2, 6/3, 7/2 or 7/3. Moist color is 10YR 3/2, 3/3, 3/4, 4/2, 4/3 or 5/3. Where it has color value of 5 dry and 3 moist it is 4 inches or less thick. Reaction is neutral, mildly or moderately alkaline.
The 2Btn horizon dry color is 10YR 5/4, 6/3, 6/4, 7/3 or 7/4. Moist color is 10YR 3/2, 3/4, 4/3, 4/4, 5/3 or 5/4. Texture is clay or sandy clay in the upper part and clay loam or sandy clay loam in the lower part. Clay content ranges from 40 to 50 percent in the upper part to 30 to 40 percent in the lower part. Sand content ranges from 30 to 50 percent. Reaction is moderately or strongly alkaline. E.C. ranges from 4 to 8 mmhos and SAR ranges from 13 to 30.
The 3Bkn horizon dry color is 2.5Y 6/2, 6/4, 7/2 or 7/4. Moist color is 2.5Y 4/2, 4/4, 5/2 or 5/4. Texture is sandy loam and coarse sandy loam in the upper part and fine sand or loamy sand in the lower part. Reaction is moderately or strongly alkaline. E.C. ranges from 4 to 8 mmhos and SAR ranges from 13 to 30.
COMPETING SERIES: These are the Bullion, Chappuis (T), Couch, Kiesel, Owinza, Tomera and Valcrest soils. Bullion soils have a mean annual soil temperature of 47 to 52 degrees F., have a silty clay or silty clay loam Btn horizons and have hues of 7.5 YR or 5 YR. Couch soils are moist only 1/4 of the time the soil temperature exceeds 41 degrees F., have a mean annual soil temperature of 49 to 52 degrees F. and have columnar structure in the upper Btn horizon. Chappuis soils have 2 to 5 percent sand in the Btn horizons. Kiesel soils have clay or silty clay Btn horizons with 20 percent or less sand. Owinza soils have columnar structure in the upper Btn horizon and have a calcic Bk horizon immediately below the Btn horizon. Tomera soils have a mean annual soil temperature of 47 to 52 degrees F., have color hue of 10YR in the C horizon and 5 to 25 percent cobbles and 30 to 70 percent gravel in the C horizon. Valcrest soils are calcareous through the solum and have a mean annual soil temperature of 47 to 52 degrees F.
GEOGRAPHIC SETTING: Standish soils are on remnant lake terraces. Slopes are 0 to 2 percent. These soils formed in lacustrine sediments from mixed sources. Elevation ranges from 3,990 to 4,300 feet. The climate is semiarid with warm dry summers and cold moist winters. The mean annual precipitation varies from 9 to 12 inches including 10 to 20 inches of snow. The mean annual temperature is about 51 degrees F. The mean January temperature is about 30 degrees F. and the mean July temperature is about 70 degrees F. The average frost-free season is 100 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Honlak(T) and Wespac(T) soils. Honlak soils are fine-loamy and are calcareous throughout the A and Btn horizons. Wespac soils are fine-loamy.
DRAINAGE AND PERMEABILITY: Well drained; runoff is slow; very slow permeability.
USE AND VEGETATION: Standish soils are used as rangeland and some small areas used for irrigated grass pasture. The vegetation in areas not cultivated is Basin big sagebrush, greasewood, basin wildrye and inland saltgrass.
DISTRIBUTION AND EXTENT: Lassen County, California. The soils of this series are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Lassen County, California, 1915.
REMARKS: This revision moves the type location to better represent the series as mapped.
Diagnostic horizons and features recognized in this pedon are:
1. Ochric epipedon - 0 to 7 inches, (A1, A2 horizons).
2. Natric horizon - 7 to 27 inches, (2Btn1, 2Btn2, 2Btnk horizons).