LOCATION TEIGEN MTEstablished Series
TAXONOMIC CLASS: Fine, smectitic, frigid Torrertic Haplustepts
TYPICAL PEDON: Teigen silty clay loam, rangeland (colors are for dry soil unless otherwise noted).
A--0 to 4 inches; gray (10YR 5/1) silty clay loam, dark gray (10YR 4/1) moist; moderate fine and very fine granular structure; slightly hard, friable, sticky and plastic; many fine and very fine roots and common medium roots; very strongly acid (pH 4.8); clear smooth boundary. (3 to 5 inches thick)
Bw1--4 to 9 inches; gray (10YR 5/1) silty clay loam, dark gray (10YR 4/1) moist; moderate medium prismatic structure parting to moderate fine subangular blocky; very hard, friable, sticky and plastic; many fine and very fine roots and common medium roots; many fine and very fine pores; very strongly acid (pH 4.8); abrupt smooth boundary. (4 to 8 inches thick)
Bw2--9 to 13 inches; light brownish gray (10YR 6/2) clay loam, dark grayish brown (10YR 4/2) moist; weak medium and fine subangular blocky structure; very hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine pores; few soft shale fragments; very strongly acid (pH 4.8); gradual wavy boundary. (3 to 6 inches thick)
Bw3--13 to 17 inches; grayish brown (10YR 5/2) clay loam, dark grayish brown (10YR 4/2) moist; weak medium and fine subangular blocky structure; very hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine pores; 5 percent soft shale fragments; very strongly acid (pH 5.0); abrupt smooth boundary. (2 to 7 inches thick)
BC--17 to 20 inches; light brownish gray (2.5Y 6/2) loam, dark grayish brown (2.5Y 4/2) moist; massive; very hard, friable, nonsticky and slightly plastic; common fine and very fine roots; many fine and very fine pores; 5 percent soft shale fragments; strongly acid (pH 5.4); abrupt smooth boundary. (0 to 5 inches thick)
C1--20 to 35 inches; grayish brown (2.5Y 5/2) clay loam, dark grayish brown (2.5Y 4/2) moist; massive with thin stratifications; very hard, friable, sticky and plastic; common fine and very fine roots; many fine and very fine pores; 5 percent soft shale fragments; slightly acid (pH 6.2); diffuse boundary. (10 to 25 inches thick)
C2--35 to 61 inches; grayish brown (2.5Y 5/2) clay loam, dark grayish brown (2.5Y 4/2) moist; massive; hard, firm, sticky and plastic; few fine and very fine roots; many fine and very fine pores; 5 percent soft shale fragments; common fine irregular filaments or threads and masses of gypsum; slightly acid (pH 6.4).
TYPE LOCATION: Fergus County, Montana; about 2,500 feet south and 1,320 feet west of the NE corner of sec. 36, T. 17 N., R. 23 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 41 to 47 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 20 inches is 41 degrees F or above.
Gypsum crystals may occur as shallow as 20 inches.
Chromas of 1 are lithochromic from shale.
A horizon - Hue: 10YR, 2.5Y, or 5Y
Value: 5 or 6 dry; 3 or 4 moist
Chroma: 1 or 2
Texture: silty clay loam or clay loam
Clay content: 30 to 40 percent
Rock fragments: 0 to 10 percent shale fragments--0 to 5 percent soft shale, 0 to 5 percent hard shale
Reaction: pH 4.5 to 6.0
Bw horizon - Hue: 10YR, 2.5Y, or 5Y
Value: 4, 5, or 6 dry; 3 or 4 moist
Chroma: 1 or 2
Texture: clay loam, silty clay loam, or silty clay
Clay content: 35 to 55 percent
Rock fragments: 0 to 10 percent shale fragments--0 to 5 percent soft shale; 0 to 5 percent hard shale
Reaction: pH 4.5 to 6.5
BC horizon - Hue: 10Y, 2.5Y, or 5Y
Value: 4, 5, or 6 dry; 3 or 4 moist
Chroma: 1 or 2
Texture: loam, silt loam, clay loam, silty clay loam, or silty clay
Clay content: 20 to 55 percent
Rock fragments: 5 to 15 percent shale fragments--5 to 10 percent soft shale, 0 to 5 percent hard shale
Reaction: pH 4.5 to 6.5
C1 horizon - Hue: 10YR, 2.5Y, or 5Y
Value: 4, 5, or 6 dry; 3 or 4 moist
Chroma: 1 or 2
Texture: mainly silty clay loam, clay loam, or silty clay; thin strata of loam in this horizon
Clay content: 35 to 55 percent
Rock fragments: 5 to 15 percent shale fragments--0 to 10 percent soft shale, 0 to 5 percent hard shale
Reaction: pH 4.5 to 6.5
C2 horizon - Hue: 10YR, 2.5Y, or 5Y
Value: 4, 5, or 6 dry; 3 or 4 moist
Chroma: 1 or 2
Texture: silty clay loam, clay loam, or silty clay
Clay content: 35 to 45 percent
Rock fragments: 5 to 15 percent shale fragments--5 to 10 percent soft shale; 0 to 5 percent hard shale
Gypsum: 0 to 5 percent
Reaction: pH 4.5 to 6.5
COMPETING SERIES:
Brunelda (MT) - has a gypsic horizon; has horizons of other salt accumulations.
Kobase (MT) - has horizons of calcium carbonate accumulation.
Megonot (MT) - 20 to 40 inches deep to a paralithic contact of shale.
Nunemaker (MT) - has horizons of carbonate and gypsum accumulations.
Welter (MT) - 20 to 40 inches deep to a paralithic contact of shale; has O and E horizons.
Zatoville (MT) - has a gypsic horizon; has a paralithic contact at a depth of 40 to 60 inches.
GEOGRAPHIC SETTING:
Landform - alluvial fans; stream terraces.
Elevation - 2,800 to 3,800 feet.
Slope- 0 to 25 percent.
Parent material - clayey alluvium derived from acid fissile shale.
Climate - long, cold winters; moist springs; hot, dry summers.
Mean annual precipitation - 10 to 14 inches.
Mean annual air temperature - 39 to 45 degrees F.
Frost-free period - 115 to 135 days.
DRAINAGE AND PERMEABILITY: Well drained; slow permeability.
USE AND VEGETATION: Teigen soils are used mainly for rangeland, and to a lesser extent dryland cropland. Potential native vegetation is mainly western wheatgrass, green needlegrass, bluebunch wheatgrass, and big sagebrush.
DISTRIBUTION AND EXTENT: Teigen soils are of moderate extent in central and eastern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Fergus County, Montana, 1979.
REMARKS: Soil interpretations record: MT0336. Diagnostic horizons and features recognized in this pedon are: an ochric epipedon from the soil surface mixed to 7 inches (A, Bw1 horizons); a cambic horizon from 4 to 17 inches (Bw1, Bw2, Bw3 horizons); and a particle-size control section from 10 to 40 inches (Bw2, Bw3, BC, C1, part of C2 horizon). Teigen soils have a frigid temperature regime and an ustic moisture regime that borders on aridic.
Classification changed from Borollic Camborthids to Aridic Ustochrepts in 1993.