LOCATION SCAIRT NDEstablished Series
TAXONOMIC CLASS: Fine, smectitic, frigid Aridic Leptic Natrustolls
TYPICAL PEDON: Scairt silt loam, in rangeland. (Colors are for dry soil unless otherwise noted)
E--0 to 2 inches; grayish brown (2.5Y 5/2) silt loam, very dark grayish brown (2.5Y 3/2) moist; moderate thin platy structure parting to moderate fine granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots throughout; many very fine low continuity tubular pores; 25 percent clay; neutral; abrupt smooth boundary. (1 to 4 inches thick)
Btn--2 to 6 inches; dark grayish brown (2.5Y 4/2) silty clay, very dark grayish brown (2.5Y 3/2) moist; moderate medium columnar structure parting to moderate fine and medium angular blocky; very hard, very firm, very sticky and very plastic; common very fine and fine roots throughout; many very fine low continuity tubular pores; 42 percent clay; grayish brown (2.5Y 5/2) dry coats on tops of columns and common faint discontinuous clay films on faces of peds; moderately alkaline; clear wavy boundary. (3 to 10 inches thick)
Btnz--6 to 13 inches; light olive brown (2.5Y 5/3) silty clay loam, olive brown (2.5Y 4/3) moist; moderate medium prismatic structure parting to moderate fine and medium angular blocky; hard, firm, sticky and plastic; common very fine roots throughout; common very fine low continuity tubular pores; 38 percent clay; few faint patchy clay films on faces of peds; common fine threads of salt masses pedogenic throughout and few fine gypsum crystals pedogenic throughout; slightly effervescent throughout (HCL, 1 normal); moderately alkaline; clear wavy boundary. (5 to 15 inches thick)
Bkz--13 to 22 inches; light yellowish brown (2.5Y 6/3) silty clay loam, olive brown (2.5Y 4/3) moist; weak medium prismatic structure parting to weak medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots throughout; common very fine low continuity tubular pores; 33 percent clay; common fine irregular salt masses pedogenic throughout and few fine gypsum crystals pedogenic throughout and common fine irregular masses of lime pedogenic throughout; strongly effervescent throughout (HCL, 1 normal); strongly alkaline; gradual wavy boundary. (0 to 15 inches thick)
BCy--22 to 28 inches; light olive gray (5Y 6/2) silty clay loam, olive gray (5Y 4/2) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots throughout; common very fine low continuity tubular pores; 33 percent clay; common fine irregular nests of gypsum pedogenic throughout; very slightly effervescent throughout (HCL, 1 normal); strongly alkaline; abrupt wavy boundary. (0 to 10 inches thick)
Cr--28 to 60 inches; light gray (5Y 7/2) and light olive gray (5Y 6/2) weathered soft bedrock, olive gray (5Y 4/2) moist.
TYPE LOCATION: Billings County, North Dakota; 1,775 feet east and 150 feet north of the southwest corner of sec. 7, T. 143 N., R. 100 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 40 to 45 degrees F.
Mollic thickness - 7 to 16 inches after mixing
Depth to soft bedrock - 20 to 40 inches
Depth to visible salts - 6 to 15 inches
E horizon - Hue 2.5Y or 10YR
Value: 5 or 6 (3 or 4 moist)
Chroma: 2 or 3
Texture: silt loam or loam
Reaction - slightly acid or neutral
Some pedons have an AE or E horizon.
Btn horizon - Hue 2.5Y or 10YR
Value: 4 to 6 (3 to 5 moist)
Chroma: 2 or 3
Texture: silty clay, silty clay loam, clay, or clay loam
Reaction - slightly alkaline to strongly alkaline
Some pedons have a Btkn or Btkny horizon.
Bk and BC horizons: Hue 2.5Y, 10YR or 5Y
Value: 4 to 6 (4 or 5 moist)
Chroma: 1 to 4
Texture: silty clay loam, silty clay or silt loam
Reaction - moderately alkaline or strongly alkaline
Some pedons have a Bky, BCk or BCky horizon.
Cr horizon - Hue 5Y, 2.5Y or 7.5YR
Value: 6 or 7 (4 or 5 moist)
Chroma: 1 to 4
COMPETING SERIES:
There are no competing series in the same family.
GEOGRAPHIC SETTING:
Landform - fans, flats and ridges on uplands and in badlands.
Elevation - 2,000 to 3,000 feet.
Slope- 0 to 25 percent.
Parent material: residuum.
Climate: cool, with long, cold winters; moist springs; warm summers.
Mean annual precipitation: 13 to 16 inches.
Mean annual air temperature: 40 to 45 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Boxwell, Cabbart, Gerda, Kirby and Maltese soils. Boxwell soils are on side slopes on uplands. They lack a natric horizon. Cabbart and Kirby soils are on knobs and ridges on uplands. Cabbart soils have soft bedrock at depths of 10 to 20 inches. Kirby soils are underlain by porcelanite at depths of 10 to 20 inches. Gerda and Maltese soils are intermixed with the Scairt soils. They do not have soft bedrock at depths of 20 to 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; very slow permeability.
USE AND VEGETATION: The Scairt soils are used as rangeland. The native vegetation is western wheatgrass, green needlegrass, inland saltgrass, and Nuttall saltbush.
DISTRIBUTION AND EXTENT: These soils are of moderate extent throughout southwestern North Dakota and possibly northwestern South Dakota and southeastern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Billings County, North Dakota, 1998.
REMARKS: Diagnostic horizons and features recognized in this pedon: mollic epipedon - the zone from the surface of the soil to a depth of 6 inches (E and Btn horizons); natric horizon - the zone from 2 to 13 inches (Btn and Btnz horizons); leptic criteria - visible salts at 6 inches (Btnz horizon).