LOCATION ABSHER MT+ND SD WYEstablished Series
TAXONOMIC CLASS: Fine, smectitic, frigid Leptic Torrertic Natrustalfs
TYPICAL PEDON: Absher silty clay, rangeland (colors are for dry soil unless otherwise noted).
E--0 to 1 inch; light brownish gray (2.5Y 6/2) loam, very dark grayish brown (2.5Y 3/2) moist; moderate very thin platy structure parting to moderate very fine and fine granular; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine and fine pores; many unstained sand grains; neutral (pH 6.6); abrupt wavy boundary. (1/4 inch to 2 inches thick)
Btn1--1 to 5 inches; grayish brown (2.5Y 5/2) silty clay, dark grayish brown (2.5Y 4/2) moist; strong medium columnar structure; extremely hard, firm, sticky and plastic; many very fine and fine roots; many very fine and fine pores and few medium pores; few faint uncoated sand grains on vertical faces of peds; continuous distinct clay films on faces of peds; slightly alkaline (pH 7.7); clear wavy boundary. (0 to 4 inches thick)
Btn2--5 to 11 inches; grayish brown (2.5Y 5/2) silty clay, dark grayish brown (2.5Y 4/2) moist; strong medium prismatic structure parting to strong fine and medium angular blocky; extremely hard, firm, sticky and plastic; many very fine and fine roots; many very fine and fine pores; continuous distinct clay films on faces of peds; slightly effervescent; moderately alkaline (pH 8.3); clear wavy boundary. (6 to 20 inches thick)
Btknyz--11 to 16 inches; grayish brown (2.5Y 5/2) silty clay, dark grayish brown (2.5Y 4/2) moist; strong fine and medium subangular blocky structure; extremely hard, friable, sticky and plastic; many very fine and fine roots; many very fine and fine pores; moderately thick continuous clay films on faces of peds; few very fine masses of lime; common fine and medium crystals of gypsum and other salts; strongly effervescent; strongly alkaline (pH 8.8); clear wavy boundary. (0 to 12 inches thick)
Bknyz--16 to 32 inches; grayish brown (2.5Y 5/2) silty clay, dark grayish brown (2.5Y 4/2) moist; massive; extremely hard, firm, sticky and plastic; many very fine and fine roots and pores; many medium and coarse crystals of gypsum and other salts; common fine threads of lime; disseminated lime; strongly effervescent; strongly alkaline (pH 8.8); clear wavy boundary. (8 to 32 inches thick)
Bkyz1--32 to 42 inches; grayish brown (2.5Y 5/2) silty clay, dark grayish brown (2.5Y 4/2) moist; massive; extremely hard, firm, sticky and plastic; common very fine and fine roots; many very fine and fine pores and few medium pores; common fine crystals of gypsum; common fine crystals of salt; few fine threads of lime; disseminated lime; slightly effervescent; strongly alkaline (pH 8.5); diffuse wavy boundary. (9 to 18 inches thick)
Bkyz2--42 to 60 inches; very pale brown (10YR 7/3) clay, grayish brown (2.5Y 5/2) and brown (10YR 5/3) moist; silt loam varves that are massive and average 1 centimeter in thickness; extremely hard, firm, sticky and plastic; few very fine and fine roots; few very fine and fine crystals of gypsum and other salts; few fine threads of lime; disseminated lime; slightly effervescent; strongly alkaline (pH 8.5).
TYPE LOCATION: Cascade County, Montana; about 2,520 feet east and 2,580 feet north of the SW corner of sec. 17, T. 19 N., R. 1 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 42 to 47 degrees F (60 to 68 degrees, summer).
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 or higher.
Depth to Btknyz horizon - 6 to 16 inches, but is mainly 8 to 15 inches.
Depth to visible gypsum or more soluble salts - less than 16 inches.
Phases- high elevation, warm, wet, gravelly.
E horizon Hue: 2.5Y, 10YR, or 7.5YR
Value: 6 or 7 dry; 3, 4, or 5 moist
Chroma: 1, 2, or 3
Texture: loam, silt loam, or fine sandy loam (where mixed with the Bt horizon, textures are mainly silty clay loam, clay loam, silty clay, clay, silt loam, or sandy clay loam)
Clay content: 15 to 55 percent
Rock fragments: 0 to 30 percent pebbles, 0 to 5 percent cobbles
Electrical conductivity: 4 to 8 mmhos/cm
Sodium Absorption Ratio: 0 to 5
Reaction: pH 6.6 to 8.4
Btn1 and Btn2 horizons - Hue: 2.5Y, 7.5YR, or 10YR
Value: 4, 5, or 6 dry; 4 or 5 moist
Chroma: 1, 2, or 3
Texture: silty clay, clay, or clay loam
Clay content: 35 to 60 percent
Structure: moderate or strong columnar or prismatic
Consistence: very hard or extremely hard when dry
Rock fragments: 0 to 15 percent pebbles
Electrical conductivity: 8 to 16 mmhos/cm
Sodium adsorption ratio: 18 to 70
Reaction: pH 6.6 to 9.6
Btknyz horizon - Hue: 2.5Y, 10YR, or 7.5YR
Value: 4, 5, or 6 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: clay loam, clay, or silty clay
Clay content: 35 to 50 percent
Rock fragments: 0 to 20 percent pebbles
Calcium carbonate equivalent: 5 to 15 percent
Electrical conductivity: 8 to 32 mmhos/cm
Sodium adsorption ratio: 18 to 70
Gypsum: 1 to 5 percent
Reaction: pH 7.9 to 9.6
Bknyz, Bkyz, Bnyz horizons - Hue: 5Y, 2.5Y, 10YR, or 7.5YR
Value: 5, 6, or 7 dry; 4, 5, or 6 moist
Chroma: 2, 3, or 4
Texture: clay loam, sandy clay loam, silty clay, clay, or silty clay loam
Clay content: 27 to 50 percent
Rock fragments: 0 to 25 percent pebbles
Calcium carbonate equivalent: 4 to 15 percent
Electrical conductivity: 8 to 32 mmhos/cm
Sodium adsorption ratio: 18 to 70
Gypsum: 1 to 5 percent
Reaction: pH 7.9 to 9.6
These horizons are slightly to violently effervescent; the lime is disseminated or in fine masses or threads. The gypsum, sodium sulfate, and other salts occur as few fine crystals to many fine masses.
Some pedons have a BCk horizon.
COMPETING SERIES: There are no other series in the same family.
GEOGRAPHIC SETTING:
Landforms- alluvial fans; stream terraces; drainageways; sedimentary plains; till plains.
Elevations- 2,000 to 5,200 feet. (Elevations extend up to 8,000 feet in Colorado and Wyoming.)
Slope- 0 to 15 percent.
Parent material - till, glaciofluvial deposits, and alluvium derived from a wide source of geologic materials.
Climate- long, cold winters; moist springs; hot, dry summers.
Mean annual precipitation - 10 to 14 inches.
Mean annual air temperature - 40 to 45 degrees F. The mean January temperature is 10 to 25 degrees F, and the mean July temperature is 64 to 72 degrees F.
Frost-free season - 95 to 135 days. (Precipitation is as low as 7 inches in Wyoming.)
DRAINAGE AND PERMEABILITY: Well and moderately well drained; very slow permeability. The moderately well drained phase has a water table at depths of 3 to 5 feet in the spring.
USE AND VEGETATION: The Absher soils are used mainly as rangeland. The native vegetation is western wheatgrass, green needlegrass, inland saltgrass, greasewood, and Nuttall saltbush.
DISTRIBUTION AND EXTENT: These soils are extensive throughout eastern Montana and in North Dakota, South Dakota, Colorado, and possibly Wyoming.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Cascade County, Montana, 1969.
REMARKS: Soil interpretation records: MT0067, MT0808, MT0856, MT0716.
Diagnostic horizons and features recognized in this pedon are: ochric epipedon - from 0 to 1 inch (E horizon); natric horizon - from 1 to 16 inches (Btn1, Btn2, Btknyz horizons); horizons of salt and gypsum accumulations (Bkyz horizons); particle-size control section - from the top of the argillic horizon to 16 inches (Btn1, Btn2, Btknyz horizons). Absher soils have an ustic moisture regime bordering on aridic and have a frigid temperature regime.
ADDITIONAL INFORMATION: Laboratory Data S71MT-13-5.