LOCATION ADIEUX CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Pachic Argixerolls
TYPICAL PEDON: Adieux sandy loam--on a south facing convex slope of 1 percent under mountain big sagebrush, bluebunch wheatgrass, Idaho fescue and Thurber needlegrass at 4,672 feet elevation. (Colors are for dry soil unless otherwise stated. When described on September 14, 1978, the soil was dry throughout.)
A--0 to 4 inches; brown (10YR 5/3) sandy loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure parting to moderate fine granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine and fine interstitial pores; 5 percent cobbles, 5 percent pebbles; neutral (pH 7.0); clear smooth boundary. (3 to 8 inches thick)
Bt1--4 to 10 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine, fine interstitial and tubular pores; many thin clay films on peds and lining pores; 5 percent cobbles, 5 percent pebbles; mildly alkaline (pH 7.5); clear smooth boundary.
Bt2--10 to 23 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; hard, firm, sticky and plastic; common very fine and fine roots; common very fine, fine interstitial and few very fine tubular pores; many moderately thick clay films on peds and lining pores; 5 percent cobbles; 5 percent pebbles; mildly alkaline (pH 7.5); gradual smooth boundary. (The combined thickness of the Bt1 and Bt2 horizons is 17 to 21 inches.)
Bt3--23 to 32 inches; yellowish brown (10YR 5/4) loam, dark yellowish brown (10YR 3/4) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; hard, firm, sticky and plastic; few very fine, fine and medium roots; few very fine, fine interstitial and few fine tubular pores; many moderately thick clay films on peds and lining pores; 5 percent cobbles, 5 percent pebbles; mildly alkaline (pH 7.5); abrupt wavy boundary. (0 to 11 inches thick)
R--32 inches; basalt.
TYPE LOCATION: Siskiyou County, California; about 12 miles east of Tulelake; about 1,500 feet south and 50 feet west of the northeast corner of section 35, T. 48 N., R. 6 E.
RANGE IN CHARACTERISTICS: The soil is 20 to 40 inches deep to a lithic contact. The mean annual soil temperature ranges from 48 to 52 degrees F. The soil temperature at a depth of 20 inches is above 41 degrees F from about March 15 to December 1 (255 days) and is above 47 degrees from about April 15 to November 15 (210 days). The soil between depths of 8 to 18 inches is dry in all parts from about July 1 to November 1 (120 days). The soil moisture control section is dry less than half the time the soil temperature is above 41 degrees F. Mollic epipedon ranges from 20 to 29 inches thick. Rock fragments make up 0 to 15 percent of the soil profile. Stones and cobbles cover 0 to 3 percent of the soil surface. Reaction is neutral or mildly alkaline.
The A horizon has dry color of 10YR 4/2, 4/3, 5/2, 5/3, or 7.5YR 5/2 and moist color of 10YR 2/2, 3/2, 3/3 or 7.5YR 3/2. Clay content ranges from 10 to 18 percent.
The Bt1 and Bt2 horizons have dry color of 10YR 5/2, 5/3 or 7.5YR 5/2 and moist color of 10YR 3/2, 3/3 or 7.5YR 3/2. Clay content ranges from 18 to 27 percent.
The Bt3 has dry color of 10YR 5/2, 5/3, 5/4, 6/3 or 7.5YR 5/4 and moist color of 10YR 3/4, 4/2, 4/3, 4/4 or 7.5YR 4/4. Clay content ranges from 18 to 27 percent.
COMPETING SERIES: These are the Banning, Blockhouse(T), Coolbirth, Dotta, Drews, Gorman, Harriman, Robinette(T), Supan, Van Dusen, Waha, Wapinitia series. Banning, Blockhouse, Coolbirth, Dotta, Drews, Gorman, Harriman, Robinette, Supan, Van Dusen and Wapinitia soils lack bedrock within depths of 40 inches. Waha soils are dry less than 80 days.
GEOGRAPHIC SETTING: Adieux soils occur in mound positions on plateaus. Slopes are 0 to 5 percent. The soils formed in residuum from basalt. Elevations are 4,200 to 4,800 feet. The climate is semi-arid with warm dry summers and cool moist winters. The average annual precipitation is about 13 to 16 inches. Snowfall is 20 to 30 inches. Mean January temperature is about 30 degrees F; mean July temperature is 65 degrees F. Mean annual temperature is about 46 to 49 degrees F. Frost-free season is about 50 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Denbar(T), Dunnlake(T), Dotta, Lequieu(T) and Salisbury soils. Denbar soils are deep and have a fine particle control section. Dunnlake soils have a fine particle control section and are shallow to bedrock. Dotta soils are greater than 60 deep. Lequieu soils are less than 10 inches deep. Salisbury soils have a fine particle control section.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeability.
USE AND VEGETATION: Adieux soils are used as rangeland. Vegetation is bluebunch wheatgrass, Idaho fescue and mountain big sagebrush.
DISTRIBUTION AND EXTENT: North central California. These soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Modoc County, California; Butte Valley-Tule Lake Soil Survey, 1986.
REMARKS: Diagnostic horizons and features recognized in the pedon are:
Mollic epipedon--zone from the surface of the soil to a depth of 23 inches (A, Bt1, Bt2)
Argillic Horizon--The zone from 4 to 32 inches (Bt1, Bt2, Bt3).
Particle-size control section the zone from 4 to 24 inches. The particle-size control section averages 22 percent clay.
Last revised by the state on 3/86.
The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data. The remainder of this document has not been updated.