LOCATION ABSAY MT
Established Series
Rev. PEM-KTS-RJS
03/2011
ABSAY SERIES
The Absay series consists of very deep, well drained soils that formed in alluvium. These soils are on stream terraces, alluvial fans and low hills. Slopes are 0 to 8 percent. Mean annual precipitation is about 12 inches, and mean annual temperature is about 41 degrees F.
TAXONOMIC CLASS: Fine, mixed, superactive, frigid Aridic Leptic Natrustalfs
TYPICAL PEDON: Absay silty clay loam, in rangeland (colors are for dry soil unless otherwise noted).
E--0 to 2 inches; light brownish gray (2.5Y 6/2) silty clay loam, dark grayish brown (2.5Y 4/2) moist; strong medium and fine angular blocky structure; hard, very firm, moderately sticky and very plastic; common very fine roots; common very fine pores; strongly effervescent; very strongly alkaline (pH 9.4); abrupt smooth boundary. (2 to 7 inches thick)
Btnz--2 to 11 inches; grayish brown (10YR 5/2) silty clay, dark grayish brown (10YR 4/2) moist; strong coarse angular blocky structure; hard, very firm, moderately sticky and very plastic; common very fine roots; common very fine pores; common distinct clay films on faces of peds; strongly effervescent; common fine threads and masses of salt; very strongly alkaline (pH 9.2); gradual irregular boundary. (5 to 18 inches thick)
Btkz--11 to 15 inches; light yellowish brown (2.5Y 6/4) silty clay loam, olive brown (2.5Y 4/4) moist; moderate coarse subangular blocky structure; hard, firm, moderately sticky and very plastic; few very fine roots; common very fine pores; common faint clay films on faces of peds; few fine masses of lime; strongly effervescent; many fine threads and masses of salts; moderately alkaline (pH 8.2); clear smooth boundary. (0 to 8 inches thick)
Bkz--15 to 60 inches; pale brown (10YR 6/3) silty clay, yellowish brown (10YR 5/4) moist; massive; hard, firm, moderately sticky and very plastic; few very fine roots; common very fine pores; disseminated lime; few fine masses of lime; violently effervescent; many medium masses and common fine threads of salt; moderately alkaline (pH 8.4).
TYPE LOCATION: Jefferson County, Montana; 1,000 feet north and 1,875 feet east of the SW corner of sec. 12, T. 1 N., R. 1 W.
RANGE IN CHARACTERISTICS:
Soil Temperature - 40 to 46 degrees F.
Moisture control section - between 4 and 12 inches, dry in all parts between four-tenths and five-tenths of the cumulative days per year when the soil temperature at a depth of 20 inches is 41 degrees F and higher.
Depth to argillic horizon - 2 to 7 inches.
Depth to the Btkz horizon - 11 to 20 inches.
Thin Bt and C horizons are allowed.
E horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 4 or 5 moist
Chroma: 2 or 3; dry or moist
Texture: silt loam or silty clay loam
Clay content: 27 to 35 percent
Rock fragments: 0 to 15 percent gravel
Electrical conductivity: 0 to 8 mmhos/cm
Sodium absorption ratio: 0 to 13
Calcium carbonate equivalent: 5 to 10 percent
Reaction: pH 7.9 to 9.5
Btnz horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2 to 6; dry or moist
Texture: silty clay loam or silty clay
Clay content: 35 to 60 percent
Rock fragments: 0 to 15 percent gravel
Electrical conductivity: 8 to 16 mmhos/cm
Sodium absorption ratio: 13 to 40
Calcium carbonate equivalent: 5 to 10 percent
Reaction: pH 8.5 to 9.5
Btkz horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 4 or 5 moist
Chroma: 3 to 6; dry or moist
Texture: silty clay loam or silty clay
Clay content: 30 to 55 percent
Rock fragments: 0 to 15 percent gravel
Electrical conductivity: more than 16 mmhos/cm
Sodium absorption ratio: 13 to 40
Calcium carbonate equivalent: 5 to 10 percent
Reaction: pH 7.9 to 9.5
Bkz horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 6 or 7 dry; 5 or 6 moist
Chroma: 3 to 6; dry or moist
Texture: loam, silt loam, silty clay loam, or silty clay
Clay content: 25 to 45 percent
Rock fragments: 0 to 15 percent gravel
Electrical conductivity: more than 16 mmhos/cm
Sodium absorption ratio: 5 to 25
Calcium carbonate equivalent: 5 to 15 percent
Reaction: pH 7.9 to 9.0
COMPETING SERIES:
There are no competing series.
GEOGRAPHIC SETTING:
Landform - stream terraces, alluvial fans and low hills.
Elevation - 3,800 to 6,000 feet.
Slope - 0 to 8 percent.
Parent material - alluvium.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 10 to 14 inches.
Mean annual air temperature - 38 to 44 degrees F.
Frost-free period - 70 to 115 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the
Dyce soil. Dyce soils are fine and do not have a natric horizon. This soil occurs on similar landforms.
DRAINAGE AND PERMEABILITY: Well drained, very slow permeability.
USE AND VEGETATION: Absay soils are mainly used for rangeland. The potential native vegetation is mainly western wheatgrass, alkali sacaton, eriogonum, nuttall saltbush, rubber rabbitbrush, and greasewood.
DISTRIBUTION AND EXTENT: Absay soils are of small extent in southwestern Montana. MLRA 44B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Jefferson County, Montana, 1998.
REMARKS: Diagnostic horizons and features recognized in this pedon are: Ochric epipedon - from 0 to 2 inches (E horizon)
Natric horizon - from 2 to 15 inches (Btnz, Btkz horizons)
Horizons of salt accumulation - from 2 to 60 inches (Btnz, Btkz, Bkz horizons)
Particle-size control section - from 2 to 15 inches (Btnz, Btkz horizons).
Absay soils have a frigid temperature regime and an ustic moisture regime bordering on aridic.
Additional Information
Classification changed from Typic Natriboralfs in 1997
Soil interpretation record: MT1552.
National Cooperative Soil Survey
U.S.A.