LOCATION LESBUT ID
Established Series
Rev. KRL/RGK/CBR
05/2018
LESBUT SERIES
Landscape--valleys, plain, alluvial plains
Landform--fan remnants, stream terraces
Slope--0 to 4 percent
Parent material--alluvium
Mean annual precipitation--about 300 mm
Mean annual air temperature--about 5 degrees C
Depth class--very deep
Drainage class--somewhat excessively drained
Soil moisture regime--aridic
Soil temperature regime--frigid
TAXONOMIC CLASS: Sandy-skeletal, mixed, frigid Calcidic Haploxerolls
TYPICAL PEDON: Lesbut gravelly loam in an area of hayland (Colors are for dry soil unless otherwise noted.)
Ap--0 to 10 cm; brown (10YR 4/3) gravelly loam, dark brown (10YR 3/3) moist; weak thick and medium platy structure; soft, very friable, slightly sticky and nonplastic; common very fine and coarse roots; many very fine and fine irregular pores; 30 percent gravel; neutral (pH 7.0); abrupt wavy boundary
Bt1--10 to 20 cm; brown (10YR 4/3) gravelly loam, dark brown (10YR 3/3) moist; weak and moderate coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and medium roots; many very fine and fine irregular pores; few thin clay films on faces of peds; 30 percent gravel; neutral (pH 7.0); clear wavy boundary
Bt2--20 to 33 cm; brown (10YR 4/3) very gravelly loam, dark brown (10YR 3/3) moist; weak and moderate medium and fine subangular blocky structure; soft, friable, slightly sticky and nonplastic; common very fine and medium roots; many very fine and fine irregular pores; few thin clay films on faces of peds; 30 percent gravel and 15 percent cobbles; neutral (pH 7.0); clear wavy boundary
Bk1--33 to 46 cm; brown (10YR 4/3) extremely gravelly sandy loam, dark brown (10YR 3/3) moist; weak coarse subangular blocky structure; soft, very friable, slightly sticky and nonplastic; common very fine and medium roots, many very fine and fine irregular pores; 55 percent gravel and 10 percent cobbles; calcium carbonate coatings 0.5 to 1.0 mm thick on bottom of rock fragments; slightly alkaline (pH 7.4); clear wavy boundary
2Bk2--46 to 69 cm; multicolored extremely gravelly sand; single grain; loose, nonsticky and nonplastic; common very fine and few fine and medium roots; common medium and coarse irregular pores; 60 percent gravel and 20 percent cobbles; calcium carbonate coatings 0.5 to 1.0 mm thick on bottom of rock fragments; slightly effervescent; slightly alkaline (pH 7.4); clear wavy boundary
2Bk3--69 to 109 cm; multicolored extremely cobbly coarse sand; single grain; loose, nonsticky and nonplastic; common very fine and few fine and medium roots; common medium and coarse irregular pores; 40 percent gravel and 40 percent cobbles; calcium carbonate coatings 0.5 to 1.0 mm thick on bottom of rock fragments; slightly effervescent; slightly alkaline (pH 7.6); gradual irregular boundary
2Bkq--109 to 150 cm; multicolored extremely cobbly coarse sand; single grain; loose, nonsticky and nonplastic; common very fine roots; common medium and coarse irregular pores; 45 percent gravel and 40 percent cobbles; calcium carbonate coatings, silica coatings, and pendular calcium carbonate nodules 0.5 to 2.0 mm thick on bottom of rock fragments; slightly effervescent; slightly alkaline (pH 7.6)
TYPE LOCATION: Butte County, Idaho; latitude 43.79722 degrees north, longitude 113.39361 degrees west, datum WGS 84
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--3.9 to 6.7 degrees C
Thickness of mollic epipedon--25 to 46 cm
Depth to secondary calcium carbonates--25 to 43 cm
Depth to lithologic discontinuity--25 to 50 cm
Particle-size control section (weighted averages)
Clay content--8 to 18 percent
Total rock fragment content--45 to 80 percent
Calcium carbonate equivalent--less than 5 percent
A horizon
Value--4 or 5 dry, 2 or 3 moist
Chroma--2 or 3 dry or moist
Clay content--12 to 22 percent
Gravel content--15 to 30 percent
Reaction--pH 6.6 to 7.8
Thickness--5 to 13 cm
Bw horizon (where present)
Value--4 to 6 dry, 2 to 4 moist
Chroma--2 or 3 dry or moist
Texture (less than 2-mm fraction)--loam, sandy loam
Clay content--8 to 22 percent
Total rock fragment content--15 to 50 percent
Gravel content--15 to 50 percent
Cobble content--0 to 10 percent
Reaction--pH 6.6 to 7.8
Thickness--0 to 13 cm
Bt horizon
Value--4 or 5 dry, 2 or 3 moist
Chroma--2 or 3 dry or moist
Clay content--8 to 18 percent
Total rock fragment content--15 to 60 percent
Gravel content--15 to 50 percent
Cobble content--10 to 20 percent
Reaction--pH 6.6 to 7.8
Thickness--10 to 43 cm
Bk1 horizon
Value--4 or 5 dry, 2 or 3 moist
Chroma--2 or 3 dry or moist
Texture (less than 2-mm fraction)--loam, sandy loam
Clay content--8 to 15 percent
Total rock fragment content--50 to 75 percent
Gravel content--45 to 60 percent
Cobble content--5 to 15 percent
Reaction--pH 7.4 to 7.8
Thickness--10 to 18 cm
2Bk2, 2Bk3, and 2Bkq horizons
Texture (less than 2-mm fraction)--coarse sand, loamy sand, loamy coarse sand, sand
Clay content--0 to 5 percent
Total rock fragment content--60 to 85 percent
Gravel content--30 to 80 percent
Cobble content--10 to 45 percent
Reaction--pH 7.4 to 7.8
Thickness--31 to 89 cm
COMPETING SERIES:
Bartonflat,
Bromaglin--calcic horizon
GEOGRAPHIC SETTING:
Elevation--1520 to 2020 m
Mean annual precipitation--200 to 425 mm
Mean annual air temperature--2.8 to 6.0 degrees C
Frost-free period--60 to 90 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--somewhat excessively drained
Saturated hydraulic conductivity (Ksat)--5 to 100 um/sec above the lithologic discontinuity, 300 to 600 um/sec below the lithologic discontinuity
USE AND VEGETATION:
Major uses--irrigated cropland and hayland
Potential natural vegetation--basin big sagebrush, bluebunch wheatgrass
DISTRIBUTION AND EXTENT: Small extent in east-central Idaho; MLRAs 11 and 12
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Custer-Lemhi County Area, Idaho; 1999
REMARKS:
Diagnostic horizons and other features recognized in this pedon
Mollic epipedon--zone from the surface to a depth of 46 cm (Ap, Bt1, Bt2, and Bk horizons)
Secondary calcium carbonates--zone from 33 to 150 cm (Bk1, 2Bk2, 2Bk3, and 2Bkq horizons)
Particle-size control section--zone from 25 to 100 cm (part of Bt2 horizon, Bk1 and 2Bk2 horizons, part of 2Bk3 horizons)
Some pedons have a cambic horizon. The Bw horizon does not meet the criteria for mollic in some areas.
Taxonomic version--Twelfth Edition, 2014
National Cooperative Soil Survey
U.S.A.