LOCATION THOSAND                 ID

Established Series
Rev. SOD/RGK/CBR
05/2018

THOSAND SERIES


Landscape--valleys, alluvial plains, plains
Landform--flood plains, stream terraces
Slope--0 to 4 percent
Parent material--alluvium
Mean annual precipitation--about 300 mm
Mean annual air temperature--about 4 degrees C
Depth class--very deep
Drainage class--poorly drained
Soil moisture regime--aquic
Soil temperature regime--cryic

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous Calcic Cryaquolls

TYPICAL PEDON: Thosand silty clay in an area of pastureland at an elevation of 1914 m (Colors are for moist soil unless otherwise noted.)

Oi--0 to 13 cm; slightly decomposed organic material; strongly effervescent

Akg--13 to 25 cm; gray (5Y 5/1) silty clay, light gray (5Y 7/1) dry; moderate medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine, fine, medium, and coarse roots; many very fine and fine tubular pores; finely disseminated calcium carbonate; violently effervescent (70 percent calcium carbonate equivalent); moderately alkaline (pH 8.4); gradual smooth boundary

Bkg1--25 to 43 cm; gray (5Y 5/1) silty clay, gray (5Y 6/1) dry; moderate fine subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; many very fine, fine, medium, and coarse roots; many very fine and fine tubular and irregular pores; finely disseminated calcium carbonate; violently effervescent; (70 percent calcium carbonate equivalent); moderately alkaline (pH 8.1); clear wavy boundary

Bkg2--43 to 69 cm; dark greenish gray (5GY 4/1) silty clay, pale olive (5Y 6/3) dry; common medium and coarse prominent dark yellowish brown (10YR 4/6) iron concentrations and common medium and coarse distinct black (5Y 2.5/2) iron depletions; moderate coarse subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common medium roots; many very fine and fine tubular and irregular pores; 10 percent gravel; finely disseminated calcium carbonate; violently effervescent (55 percent calcium carbonate equivalent); moderately alkaline (pH 8.0); clear wavy boundary

Bkg3--69 to 112 cm; greenish gray (5GY 5/1) gravelly loam, light olive gray (5Y 6/2) dry; many medium and coarse prominent dark yellowish brown (10YR 4/6) iron concentrations and common medium and coarse distinct dark bluish gray (5B 4/1) iron depletions; moderate coarse subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few coarse roots; many very fine and fine tubular and irregular pores; 30 percent gravel; slightly effervescent (1 percent calcium carbonate equivalent); moderately alkaline (pH 8.2); clear wavy boundary

Bkg4--112 to 125 cm; olive gray (5Y 4/2) very gravelly silty clay loam, pale olive (5Y 6/3) dry; moderate coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common medium roots; many very fine and fine tubular and irregular pores; 55 percent gravel; slightly effervescent (1 percent calcium carbonate equivalent); moderately alkaline (pH 8.2); clear wavy boundary

2Cg--125 to 165 cm; dark gray (5Y 4/1) extremely gravelly loamy coarse sand, gray (5Y 6/1) dry; massive; slightly hard, friable, nonsticky and nonplastic; common very fine, fine, and medium tubular and interstitial pores; 65 percent gravel; slightly effervescent; (1 percent calcium carbonate equivalent); moderately alkaline (pH 8.1)

TYPE LOCATION: Custer County, Idaho; latitude 44.10056 degrees north, longitude 113. 87778 degrees west, datum WGS 84

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--2.8 to 6.1 degrees C
Thickness of mollic epipedon--18 to 38 cm
Calcium carbonate equivalent of mollic epipedon--40 to 75 percent
Depth to lithologic discontinuity--100 to 150 cm

Particle-size control section (weighted averages)
Clay content--20 to 35 percent
Total rock fragment content--5 to 30 percent

Oi horizon (where present)
Texture--slightly decomposed plant material
Organic matter content--60 to 95 percent
Reaction--pH 4.0 to 5.5
Thickness--0 to 15 cm

Akg horizon
Hue--10YR, 2.5YR, or 5Y moist or dry
Value--4 or 5 moist, 6 or 7 dry
Chroma--1 or 2 moist or dry
Texture (less than 2-mm fraction)--silt loam, silty clay
Clay content--15 to 55 percent
Calcium carbonate equivalent--40 to 75 percent
Reaction--pH 7.4 to 8.4
Thickness--8 to 18 cm

Bkg1 and Bkg2 horizons
Hue--2.5Y, 5Y, or 5GY moist or dry
Value--4 to 6 moist, 6 or 7 dry
Chroma--1 to 3 moist or dry
Texture (less than 2-mm fraction)--silt loam, silty clay, silty clay loam, loam, sandy loam
Clay content--15 to 55 percent
Gravel content--0 to 30 percent
Calcium carbonate equivalent--5 to 75 percent
Reaction--pH 7.4 to 8.4
Thickness--21 to 96 cm

Bkg3 and Bkg4 horizons
Hue--2.5Y, 5Y, or 5GY moist or dry
Value--4 or 5 moist, 5 or 6 dry
Chroma--1 to 3 moist or dry
Texture (less than 2-mm fraction)--silt loam, silty clay loam, loam, sandy loam
Clay content--10 to 40 percent
Gravel content--0 to 55 percent
Calcium carbonate equivalent--1 to 20 percent
Reaction--pH 7.4 to 8.4
Thickness--28 to 89 cm

2Cg horizon
Hue--5Y or 5GY moist or dry
Value--4 to 6 moist or dry
Chroma--1 or 2 moist or dry
Texture (less than 2-mm fraction)--loamy sand, loamy coarse sand
Clay content--2 to 10 percent
Gravel content--60 to 80 percent
Calcium carbonate equivalent--0 to 10 percent
Reaction--pH 7.4 to 8.4
Thickness--28 to 89 cm

COMPETING SERIES:
Bigrant--no lithologic discontinuity
Horsegrass--less than 40 percent calcium carbonate equivalent in mollic epipedon

GEOGRAPHIC SETTING:
Elevation--1460 to 2020 m
Mean annual precipitation--225 to 425 mm
Mean annual air temperature--1.7 to 6.0 degrees C
Frost-free period--20 to 75 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--poorly drained
Depth to seasonal high water table--30 cm above the surface to a depth of 46 cm below the surface
Saturated hydraulic conductivity (Ksat)--0.1 to 50 um/sec in upper part, 100 to 700 um/sec below the lithologic discontinuity

USE AND VEGETATION:
Major use--pastureland
Potential natural vegetation--beaked sedge, northwestern sedge, Nebraska sedge, woollyfruit sedge, water sedge, water speedwell

DISTRIBUTION AND EXTENT: Small extent in east-central Idaho; MLRA 12

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Custer County, Idaho; 1999

REMARKS:
Diagnostic horizons and other features recognized in this pedon
Mollic epipedon--zone from 13 to 43 cm (Akg and Bkg1 horizons) (Dry and moist color value is waived for greater than 40 percent calcium carbonate.)
Calcic horizon--zone from 13 to 69 cm (Akg, Bkg1, and Bkg2 horizons)
Aquic conditions--zone from the surface to a depth of 165 cm
Particle-size control section--zone from 38 to 113 cm (Bkg1 and Bkg2 horizons, part of Bkg3 horizon)

ADDITIONAL DATA:
Laboratory data--pedon number 87ID037004; Kellogg Soil Survey Laboratory, Lincoln, NE

Taxonomic version--Twelfth Edition, 2014


National Cooperative Soil Survey
U.S.A.