LOCATION YAGO IDEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, smectitic, frigid Typic Argixerolls
TYPICAL PEDON: Yago extremely stony silty clay loam - on a mountain slope at 6,000 feet elevation. (Colors are for air-dry soil unless otherwise noted.)
A--0 to 10 inches; dark grayish brown (10YR 4/2) extremely stony silty clay loam, very dark grayish brown (10YR 3/2) moist; moderate medium and fine subangular blocky structure; hard, firm, sticky and plastic; common very fine, fine, and medium roots, and few coarse roots; many very fine irregular pores along the faces of peds and common very fine and fine tubular pores; about 10 percent gravel, 30 percent cobbles, and 20 percent stones; slightly acid (pH 6.5); abrupt irregular boundary. (8 to 14 inches thick)
Bt1--10 to 16 inches; brown (7.5YR 5/4) very stony clay loam, dark brown (7.5YR 4/4) moist; moderate medium and fine angular blocky structure; very hard, very firm, very sticky and very plastic; common very fine and fine roots; common very fine irregular pores along the faces of peds and common very fine and fine tubular pores; few thin clay films on the faces of peds and in pores; about 10 percent gravel, 30 percent cobbles, and 20 percent stones; slightly acid (pH 6.5); gradual irregular boundary. (4 to 8 inches thick)
Bt2--16 to 37 inches; brown (7.5YR 5/4) very stony clay loam, dark brown (7.5YR 4/4) moist; moderate coarse and medium angular blocky structure; extremely hard, very firm, very sticky and very plastic; common very fine and few fine roots; common very fine irregular pores along faces of peds and few very fine tubular pores; many moderately thick clay films on faces of peds and in pores; about 10 percent gravel, 30 percent cobbles, and 20 percent stones; neutral (pH 6.7); abrupt irregular boundary. (17 to 25 inches thick)
Btk1--37 to 45 inches; light brown (7.5YR 6/4) very stony clay loam, brown (7.5YR 5/4) moist; moderate coarse and medium angular blocky structure; extremely hard, very firm, very sticky and very plastic; common very fine roots; common very fine irregular pores along faces of peds; common moderately thick clay films on faces of peds and in pores; about 10 percent gravel, 30 percent cobbles, and 20 percent stones; common thin coats of calcium carbonate on faces of peds; neutral (pH 7.2); clear wavy boundary. (6 to 10 inches thick)
Bkc--45 to 60 inches; reddish yellow (7.5YR 6/6) very stony silty clay loam, strong brown (7.5YR 5/6) moist; massive; slightly hard, friable, sticky and slightly plastic; few very fine and fine roots; few very fine tubular pores; about 10 percent gravel, 30 percent cobbles, and 20 percent stones; many fine rounded iron and manganese concretions; strongly effervescent; mildly alkaline (pH 7.4).
TYPE LOCATION: Bannock County, Idaho; about 3 miles northeast of Lava Hot Springs; 860 feet south and 900 feet west of the northeast corner of section 24, T. 9 S., R. 38 E.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon - 10 to 20 inches
Average annual soil temperature - 42 to 45 degrees F.
Depth to lime - 36 to more than 60 inches
Clay content in the control section - 35 to 50 percent
Rock fragment content in the control section - 40 to 60 percent
A horizon
Color hue - 10YR or 7.5YR
Value, dry - 3 through 5
Value, moist - 2 or 3
Chroma, moist or dry - 2 or 3
Reaction - moderatey acid to neutral
Bt and Btk horizons
Color hue - 5YR or 7.5YR
Value, dry - 4 through 6
Value, moist - 4 or 5
Chroma, moist or dry - 4 through 6
Clay content - 35 to 50
Rock fragments - 40 to 60 percent
Reaction - slightly acid or neutral
Texture - STV-CL, STV-SICL, STV-C, CBV-CL, CBV-SICL
Bkc horizon
Color hue - 5YR through 10YR
Value, dry - 5 or 6
Value, moist - 4 or 5
Chroma, moist or dry - 4 through 6
Clay content - 23 through 34 percent
Rock fragments - 40 to 60
Reaction - neutral or mildly alkaline
Texture - STV-SIL, STV-SICL, CBV-SICL, CBV-SIL
COMPETING SERIES: These are the Birchcreek, Derringer, Droem (T), Erakatak, Leevan, McIvey, Ravenswood, Roosercomb, Sharesnout, Threek, and Yeates Hollow series. Birchcreek, Droem, Erakatak, Leevan, Ravenswood, Roostercomb, and Sharesnout series are moderately deep. Derringer soils are moderately deep to a paralithic contact. McIvey and Yeates Hollow soils lack accumulations of carbonates. Threek soils have accumulations of silica below the argillic and have a lithologic discontinuity.
GEOGRAPHIC SETTING: Yago soils are on mountain slopes and fan terraces and have slopes of 4 to 40 percent. These soils formed in mixed alluvium and colluvium derived dominantly from quartzite and sandstone. Average annual precipitation is 16 to 22 inches. Average annual temperature is 40 to 44 degrees F. Frost-free season is 65 to 80 days. Elevation ranges from 5,600 to 7,000 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bancroft, Broadhead, Camelback (T), Hades, Manila, and Valmar (T) soils. Bancroft soils are fine-silty and are on level to gently sloping broad fan terraces. Broadhead soils are pachic and are generally on north and east-facing concave toeslopes and fan terraces in landscape positions similar to Yago. Camelback soils are pachic and are on north and east-facing convex slopes. Hades soils are fine-loamy and pachic and are in mound areas with Yago soils in intermound areas of patterned ground. Manila soils have less than 35 percent rock fragments and are generally on south and west-facing slopes in slightly concave positions where associated with Yago. Valmar soils are loamy-skeletal and are on the upper part of slightly convex slopes and on ridgetops.
DRAINAGE AND PERMEABILITY: Well drained; slow to very rapid runoff; slow permeability.
USE AND VEGETATION: These soils are mostly used as rangeland. Vegetation is mainly mountain big sagebrush, antelope bitterbrush, western snowberry, serviceberry, bluebunch wheatgrass, slender wheatgrass, bluegrass, and mulesear wyethia.
DISTRIBUTION AND EXTENT: Southeastern Idaho. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Bannock County, Idaho, 1983.