LOCATION SWAMPYDRAW ID
Established Series
IRD KA/RGK/CBR
05/2018
SWAMPYDRAW SERIES
Landscape--hills, alluvial plains
Landform--fan remnants
Slope--1 to 60 percent
Parent material--loess-influenced alluvium
Mean annual precipitation--about 350 mm
Mean annual air temperature--about 4.4 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--frigid
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Calcic Argixerolls
TYPICAL PEDON: Swampydraw gravelly silt loam in an area of rangeland (Colors are for dry soil unless otherwise stated.)
A1--0 to 3 cm; very dark grayish brown (10YR 3/2) gravelly silt loam, very dark brown (10YR 2/2) moist; moderate medium granular structure; soft, very friable, slightly sticky and slightly plastic; many fine and very fine, common medium, and few coarse roots; common very fine tubular pores; 30 percent gravel; neutral (pH 7.2); clear wavy boundary
A2--3 to 8 cm; very dark grayish brown (10YR 3/2) silt loam, very dark brown (10YR 2/2) moist; weak medium and fine subangular blocky structure parting to moderate medium granular; soft, very friable, slightly sticky and slightly plastic; many fine and very fine, common medium, and few coarse roots; common very fine tubular pores; 10 percent gravel; neutral (pH 7.2); clear wavy boundary
A3--8 to 20 cm; dark grayish brown (10YR 4/2) silt loam, very dark grayish brown (10YR 3/2) moist; moderate medium and fine subangular blocky structure parting to moderate coarse and medium granular; soft, very friable, slightly sticky and slightly plastic; many fine and very fine, common medium, and few coarse roots; common very fine tubular pores; 10 percent gravel; neutral (pH 7.2); clear smooth boundary
2Bt1--20 to 33 cm; grayish brown (10YR 5/2) very gravelly clay loam, dark brown (10YR 3/3) moist; strong medium and fine prismatic structure parting to strong coarse and medium subangular blocky; slightly hard, firm, sticky and plastic; many fine and very fine, common medium, and few coarse roots; common fine and very fine tubular pores; many thin clay films on ped faces and in pores; 35 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.4); clear smooth boundary
2Bt2--33 to 58 cm; yellowish brown (10YR 5/4) very gravelly clay loam, dark yellowish brown (10YR 4/4) moist; strong coarse and medium prismatic structure parting to strong coarse and medium subangular blocky; hard, very firm, sticky and plastic; common fine, very fine, and medium roots; many fine and very fine tubular pores; many moderately thick clay films on ped faces and in pores; 35 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.4); clear wavy boundary
2Bk1--58 to 74 cm; pale brown (10YR 6/3) very gravelly loam, brown (10YR 4/3) moist; weak medium and fine subangular blocky structure; slightly hard, firm, slightly sticky and plastic; common fine and very fine and few medium roots; common fine and very fine tubular pores; calcium carbonate coatings on bottom of rock fragments; 40 percent gravel and 5 percent cobbles; violently effervescent (12 percent calcium carbonate equivalent); moderately alkaline (pH 8.0); abrupt wavy boundary
3Bk2--74 to 127 cm; pink (7.5YR 7/4) extremely gravelly sandy loam, light brown (7.5YR 6/4) moist; weak medium and fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; few medium, fine, and very fine roots; few very fine tubular pores; calcium carbonate coatings on bottom of rock fragments; 70 percent gravel and 10 percent cobbles; violently effervescent (30 percent calcium carbonate equivalent); moderately alkaline (pH 8.4); clear wavy boundary
3Bk3--127 to 155 cm; pink (7.5YR 7/4) extremely gravelly coarse sandy loam, strong brown (7.5YR 5/6) moist; weak medium and fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; calcium carbonate coatings on bottom of rock fragments; 70 percent gravel and 10 percent cobbles; violently effervescent (12 percent calcium carbonate equivalent); strongly alkaline (pH 8.6)
TYPE LOCATION: Clark County, Idaho; latitude 44.32072 degrees north, longitude 112.45515 degrees west, datum WGS 84
RANGE IN CHARACTERISTICS:
Mean annual soil temperature--2.8 to 7.2 degrees C
Thickness of mollic epipedon--20 to 40 cm
Depth to argillic horizon--15 to 25 cm
Depth to secondary calcium carbonates--30 to 76 cm
Particle-size control section (weighted averages)
Clay content--20 to 35 percent
Total rock fragment content--35 to 50 percent
A horizon
Value--3 or 4 dry, 2 or 3 moist
Chroma--2 or 3 dry or moist
Clay content--5 to 18 percent
Total rock fragment content--5 to 35 percent
Gravel content--5 to 35 percent
Reaction--pH 6.8 to 7.4
Thickness--16 to 26 cm
2Bt horizon
Hue--10YR or 7.5YR dry or moist
Value--3 to 6 dry, 2 to 5 moist
Chroma--2 to 4 dry or moist
Texture (less than 2-mm fraction)--clay loam, loam
Clay content--20 to 35 percent
Total rock fragment content--35 to 50 percent
Gravel content--35 to 45 percent
Cobble content--0 to 5 percent
Reaction--pH 6.8 to 7.6
Thickness--30 to 51 cm
2Bk1 horizon
Hue--10YR or 7.5YR dry or moist
Value--5 to 8 dry, 4 to 7 moist
Chroma--1 to 6 dry or moist
Texture (less than 2-mm fraction)--clay loam, loam
Clay content--20 to 35 percent
Total rock fragment content--35 to 50 percent
Gravel content--35 to 45 percent
Cobble content--0 to 5 percent
Calcium carbonate equivalent--10 to 15 percent
Reaction--pH 7.9 to 8.4
Thickness--15 to 41 cm
3Bk2 and 3Bk3 horizons
Hue--10YR or 7.5YR dry or moist
Value--5 to 8 dry, 4 to 7 moist
Chroma--2 to 6 dry or moist
Texture (less than 2-mm fraction)--coarse sandy loam, loam, sandy loam
Clay content--5 to 15 percent
Total rock fragment content--60 to 85 percent
Gravel content--55 to 80 percent
Cobble content--5 to 15 percent
Calcium carbonate equivalent--10 to 30 percent
Reaction--pH 7.9 to 8.4
COMPETING SERIES:
Amelar,
Dra--secondary calcium carbonates in argillic horizon
Broad,
Milk,
Sheep Creek,
Small--moderately deep to lithic contact
Custco--no lithologic discontinuity
Drage,
Searla--no calcic horizon
Rawnjay--15 to 50 percent of surface covered with rock fragments
Remount--more than 60 percent rock fragments in argillic horizon
Scalfar--argillic horizon at a depth of less than 15 cm
GEOGRAPHIC SETTING:
Elevation--1580 to 2400 m
Mean annual precipitation--200 to 575 mm
Mean annual air temperature--1.7 to 6.1 degrees C
Frost-free period--50 to 95 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--1 to 100 um/sec
USE AND VEGETATION:
Major uses--rangeland, wildlife habitat
Potential natural vegetation--mountain big sagebrush, Saskatoon serviceberry, Idaho fescue, bluebunch wheatgrass, arrowleaf balsamroot
DISTRIBUTION AND EXTENT: Small extent in southeastern Idaho; MLRA 12
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Clark County, Idaho; 2018
REMARKS:
Diagnostic horizons and other features recognized in this pedon
Mollic epipedon--zone from the surface to a depth of 33 cm (A and 2Bt1 horizons)
Argillic horizon--zone from 20 to 58 cm (2Bt horizon)
Calcic horizon--zone from 58 to 155 cm (2Bk1, 3Bk2, and 3Bk3 horizons)
Particle-size control section--zone from 20 to 58 cm (2Bt horizon)
Taxonomic version--Twelfth Edition, 2014
National Cooperative Soil Survey
U.S.A.