LOCATION MCDERMOTT CAEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Xeric Natrargids
TYPICAL PEDON: McDermott silt loam, rangeland, on a 3 percent slope under a cover of big sagebrush, greasewood, spiny hopsage, horsebrush and creeping wildrye. (When described, June 17, 1983, the soil was dry throughout. Colors are for dry soil unless otherwise noted).
A1--0 to 3 inches; light gray (2.5Y 7/2) silt loam, grayish brown (2.5Y 5/2) moist; moderate fine platy structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine roots; many very fine tubular pores; slightly effervescent with disseminated lime; strongly alkaline (pH 8.5); abrupt wavy boundary.
A2--3 to 6 inches; light gray (2.5Y 7/2) silt loam, grayish brown (2.5Y 5/2) moist; strong medium platy structure; slightly hard, very friable, sticky and plastic; common very fine and fine, and few medium roots; many very fine tubular pores; slightly effervescent with disseminated lime; strongly alkaline (pH 8.5); clear wavy boundary.
A3--6 to 13 inches; pale yellow (2.5Y 8/2) silt loam, light yellowish brown (2.5Y 6/4) moist; moderate medium angular blocky structure; slightly hard, very friable, sticky and plastic; few very fine, common fine and few medium roots; common very fine tubular pores; violently effervescent, lime segregated in common fine soft masses; strongly alkaline (pH 8.5); clear wavy boundary. (The combined thickness of the A horizons is 4 to 17 inches)
BAtkn1--13 to 19 inches; pale yellow (2.5Y 8/2) clay loam, light yellowish brown (2.5Y 6/4) moist; strong fine and medium angular blocky structure; slightly hard, very friable, sticky and plastic; few very fine and fine roots; common very fine tubular pores; many thin clay films on peds and in pores; violently effervescent, lime segregated in common fine soft masses; SAR is 11; E.C. is 0.72 mmhos; strongly alkaline (pH 8.5); clear wavy boundary.
BAtkn2--19 to 25 inches; light gray (2.5Y 7/2) silty clay loam, light yellowish brown (2.5Y 6/3) moist; moderate medium prismatic structure parting to weak medium angular blocky; hard, firm, sticky and plastic, few fine roots, common very fine tubular pores; many thin clay films on peds and in pores; violently effervescent, lime segregated in common fine soft filaments; SAR is 19; E.C. is 0.87 mmhos; strongly alkaline (pH 8.5); gradual wavy boundary. (The combined thickness of the BAtkn horizons is 10 to 18 inches)
2Btkn1--25 to 35 inches; pale yellow (2.5Y 8/2) clay loam, light yellowish brown (2.5Y 6/4) moist; moderate medium prismatic structure, breaking to strong medium angular blocky structure; slightly hard, very friable, sticky and plastic; few very fine, common fine and few medium roots; common very fine tubular pores; continuous thin clay films on peds and in pores; violently effervescent, lime segregated in common fine soft masses; SAR is 23; E.C. is 1 mmhos; strongly alkaline (pH 8.5); gradual wavy boundary.
2Btkn2--35 to 50 inches; pale yellow (2.5Y 8/2) clay loam, light yellowish brown (2.5Y 6/4) moist; strong prismatic structure parting to strong medium angular blocky; hard, friable, sticky and plastic; few very fine, common fine and few medium roots; many very fine tubular pores; nearly continuous thin clay films on peds and lining pores; violently effervescent, lime segregated in many fine soft filaments; SAR is 8; E.C. is 1.4 mmhos; strongly alkaline (pH 8.5), gradual wavy boundary. (The combined thickness of the 2Btk horizons is 20 to 28 inches).
2BCk--50 to 60 inches; light brownish gray (2.5Y 6/2) silt loam, dark grayish brown (2.5Y 4/2) moist; weak medium prismatic structure parting to moderate fine angular blocky; hard, firm, sticky and plastic; slightly effervescent, lime segregated in common fine soft filaments; strongly alkaline (pH 8.5).
TYPE LOCATION: Lassen County, California; on "The Island" north side of main NE-SW dirt road at a point 0.85 mile E of last E fork in the road; 700 feet N and 2,600 feet W of SE corner of section 3, T.27 N., R.15 E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature varies from 53 to 56 degrees F. Depth to carbonates is 0 to 4 inches. Reaction is moderately to strongly alkaline. The control section has a weighted average of 27 to 35 percent clay. These soils are dry in all parts of the moisture control section (6 to 19 inches) from June 1 to November 15 (167 days) and moist in all parts from December 1 to April 15. The soil temperature exceeds 41 degrees F from March 1 to December 1 (275 days) and exceeds 47 degrees F from April 15 to November 1.
The A horizon is 10YR 7/2, 6/2, 2.5Y 8/2, 7/2 or 6/2. Moist color is 10YR 4/3, 3/2, 2.5Y 6/4, 5/4, 5/2, 4/4 or 4/2. It is noneffervescent to strongly effervescent.
The BAtkn and 2Btkn horizons are 10YR 7/3, 6/3; 2.5Y 8/2, 7/2, 7/4, 6/2 or 5Y 6/3. Moist color is 10YR 5/4, 4/4; 2.5Y 6/4, 6/3; 5Y 5/4, 5/3, 4/3 or 4/2. Texture is clay loam, silt loam or silty clay loam. Lime is disseminated, in filaments or in irregular soft masses. Between the depths of 40 to 60 inches, some pedons have 30 to 40 percent hard firm 10 to 30 mm durinodes. SAR ranges from 11 to 30. E.C. ranges from 0 to 2 mmhos.
COMPETING SERIES: There are no other soils in this family.
GEOGRAPHIC SETTING: McDermott soils are on remnant, uplifted lake terraces. Slopes are 0 to 5 percent. These soils formed in lacustrine sediments from mixed rock sources. Elevation is 4,000 to 4,050 feet. The climate is arid with warm, dry summers and cold, somewhat moist winters. The mean annual precipitation is 6 to 9 inches. The mean annual temperature is 49 to 52 degrees F. Mean July temperature is about 72 degrees F, and mean January temperature is about 30 degrees F. The frost-free season is 100 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Calneva, Herlong, Lieberman, Mazuma and Stiles soils. All these soils occur on lake terraces. Calneva soils are in the fine family. Herlong soils have a petrocalcic horizon. Lieberman soils have a calcic horizon. Mazuma soils are coarse-loamy and have no diagnostic subhorizons. Stiles soils are moderately deep to tuff.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderately slow permeability.
USE AND VEGETATION: Used as rangeland. The vegetation is big sagebrush, greasewood, and basin wildrye.
DISTRIBUTION AND EXTENT: Northeastern California, eastern Lassen County in the Honey Lake Valley. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Susanville Area Soil Survey Area, 1985.
MCDERMOTT is the name of a nearby canyon.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the surface to a depth of 13 inches (A1, A2, A3 horizons).
Natric horizon - The zone from 25 to 35 inches (2Btkn1 horizon).
This pedon sampled for full characterization on August 20, 1984. (S84CA035-01)