LOCATION DOUGHTY MTEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Typic Argiustolls
TYPICAL PEDON: Doughty loam, rangeland (colors are for dry soil unless otherwise noted).
A--0 to 5 inches; dark grayish brown (10YR 4/2) loam, black (10YR 2/1) moist; moderate fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine and very fine roots; less than 5 percent pebbles; neutral (pH 7.2); clear wavy boundary (4 to 8 inches thick)
Bt--5 to 14 inches; brown (10YR 4/3) clay loam, dark brown (10YR 3/3) moist; strong medium prismatic parting to strong medium and fine subangular blocky structure, hard, friable, moderately sticky and moderately plastic; many fine and very fine roots; many fine and very fine pores; continuous faint clay films on peds; very dark grayish brown (10YR 3/2) organic stains on peds; less than 5 percent pebbles; neutral (pH 7/2); abrupt irregular boundary. (6 to 11 inches thick)
Bk1--14 to 20 inches; pale brown (10YR 6/3) light clay loam, brown (10YR 4/3) moist; moderate medium and fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine pores; 5 percent limestone pebbles; disseminated lime, few fine masses of lime; violently effervescent; moderately alkaline (pH 8.0); gradual wavy boundary.
Bk2--20 to 32 inches; very pale brown (10YR 7/3) light clay loam, brown (10YR 5/3) moist; weak medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and very fine roots; many fine and very fine pores; 10 percent limestone pebbles; many fine masses and threads of lime; violently effervescent moderately alkaline (pH 8.4); abrupt wavy boundary. (Combined thickness of Bk horizons is 6 to 25 inches.)
2Ck1--32 to 42 inches; very pale brown (10YR 7/3) extremely gravelly loam, light brownish gray (10YR 6/2) moist; massive; hard, friable, slightly sticky and slightly plastic; few fine and very fine roots; common fine and very fine pores; 65 percent rock fragments consisting of 85 percent pebbles and 15 percent cobbles; violently effervescent; moderately alkaline (pH 8.4); clear wavy boundary (8 to 20 inches thick)
2Ck2--42 to 66 inches; very pale brown (10YR 7/3) extremely gravelly sandy clay loam, pale brown (10YR 6/3) moist; massive; soft, very friable, slightly sticky and nonplastic; few very fine roots; 75 percent rock fragments consisting of 85 percent pebbles and 15 percent cobbles; violently effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Fergus County, Montana, about 400 feet west and 1,400 feet south of NE corner sec. 16. T. 14 N., R. 16 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 39 to 45 degrees F.
Moisture control section - between 4 and 12 inches; not dry in all parts for 45 consecutive days.
Mollic epipedon thickness - 10 to 16 inches.
Depth to Bk horizon - 10 to 24 inches.
Depth to 2C horizon - 20 to 40 inches.
A horizon - Value: 3 or 4 dry; 2 or 3 moist
Chroma: 1 or 2
Clay content: 18 to 27 percent
Rock fragments: 0 to 25 percent--0 to 15 percent cobbles; 0 to 10 percent pebbles
Reaction: pH 6.1 to 7.8
Bt horizon - Value: 4 or 5 dry; 3 or 4 moist
Chroma: 2 or 3
Texture: clay loam and silty clay loam
Clay content: 27 to 35 percent
Rock fragments: 0 to 20 percent--0 to 5 percent cobbles; 0 to 15 percent pebbles
Reaction: pH 6.6 to 7.8
Bk1 horizon - Value: 5, 6, 7, or 8 dry; 4, 5, or 6 moist
Chroma: 2 or 3
Texture: clay loam and loam
Clay content: 18 to 32 percent
Rock fragments: 0 to 35 percent--0 to 10 percent cobbles; 0 to 25 percent pebbles
Calcium Carbonate Equivalent: 15 to 40 percent
Reaction: pH 7.4 to 8.4
Bk2 horizon - Value: 7 or 8 dry; 5 or 6 moist
Chroma: 2 or 3
Texture: clay loam and loam
Clay content: 18 to 32 percent
Rock fragments: 0 to 35 percent--0 to 10 percent cobbles; 0 to 25 percent pebbles
Calcium Carbonate Equivalent: 15 to 40 percent
Reaction: pH 7.4 to 8.4
2Ck1 horizon - Value: 7 or 8 dry; 5 or 6 moist
Chroma: 2 or 3
Texture: loam, sandy clay loam, and sandy loam
Clay content: 15 to 25 percent
Rock fragments: 50 to 70 percent--trace of stones; 5 to 10 percent cobbles; 45 to 60 percent pebbles
Calcium carbonate equivalent: 15 to 40 percent
Reaction: pH 7.9 to 9.0
2Ck2 horizon - Hue: 10YR or 2.5Y
Value: 7 or 8 dry; 5 or 6 moist
Chroma: 2 or 3
Texture: sandy loam, sandy clay loam, and loam
Clay content: 5 to 20 percent
Rock fragments: 40 to 85 percent--10 to 15 percent cobbles; 30 to 70 percent pebbles
Calcium carbonate equivalent: 15 to 40 percent
Reaction: pH 7.9 to 9.0
COMPETING SERIES:
Absarook (MT) - has a lithic contact at 20 to 40 inches.
Archmesa (CO) - has a lithic contact at 20 to 40 inches.
Beartooth (MT) - has an O horizon; is skeletal in the Bk horizons.
Bielenberg (MT) - has a paralithic contact at 40 to 60 inches.
Bookcliff (UT) - has a lithic contact at 40 to 60 inches.
Burtoner (MT) - has a paralithic contact at 20 to 38 inches.
Clancy (MT) - has a lithic contact above a depth of 60 inches.
Clasoil (MT) - does not have horizons of secondary carbonate accumulation.
Dooley (MT) - does not have a calcic horizon.
Empedrado (CO) - does not have a calcic horizon.
Fairfield (MT) - depth to the base of the argillic is 10 inches or less.
Farnuf (MT) - does not have a calcic horizon.
Farside (MT) - does not have a calcic horizon.
Felor (SD) - has a discontinuity of clayey sediments at 20 to 35 inches.
Greenway (SD) - has a discontinuity of till at 15 to 25 inches.
Gurney (SD) - has a lithic contact at of 20 to 40 inches.
Hangdo (UT) - does not have horizons of secondary carbonate accumulation.
Hoppers (MT) - has a lithic contact at 20 to 40 inches.
Hyalite (MT) - has a sandy-skeletal discontinuity below the argillic horizon.
Jeffcity (MT) - has paralithic and lithic contacts at 20 to 40 inches.
Kokoruda (MT) - does not have horizons of secondary carbonate accumulation.
Livona (ND) - does not have a calcic horizon.
Martinsdale (MT) - does not have a lithologic discontinuity.
Maudlin (CO) - has a lithic contact between depths of 20 to 40 inches.
Meagher (MT) - have a lithologic discontinuity in the Bk horizon.
Moen (CO) - has a lithic contact at of 20 to 40 inches.
Moento (CO) - has a lithic contact at 20 to 40 inches.
Pianohill (MT) - has a lithic contact of mudflow breccia at 20 to 40 inches.
Placerton (MT) - has a lithic contact above 60 inches.
Reeder (ND) - has a paralithic contact at of 20 to 40 inches.
Reedwest (MT) - has a paralithic contact at 20 to 40 inches.
Sipple (MT) - is greater than 40 inches to a lithologic discontinuity.
Snakejohn (UT) - has a lithic contact at 40 to 60 inches.
Sponseller (AZ) - has hues redder than 10YR throughout the profile.
Tragmon (CO) - does not have horizons of secondary carbonate accumulation.
Trazuni (NM) - does not have horizons of secondary carbonate accumulation.
Ulrant (WY) - has a lithic contact at 40 to 60 inches.
Vida (MT) - does not have a calcic horizon.
Watne (MT) - does not have a lithologic discontinuity.
Watrous (ND) - has a lithic contact at 20 to 40 inches.
Williams (ND) - does not have a lithologic discontinuity; formed in till.
Yegen (MT) - does not have a calcic horizon.
GEOGRAPHIC SETTING:
Landform - alluvial fans and stream terraces.
Elevation - 4,000 to 6,000 feet.
Slope - 0 to 15 percent.
Parent material - alluvium.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 17 to 24 inches
Mean annual temperature - 37 to 42 degrees F.
Frost-free period - 75 to 110 days.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability above the 2C horizon; moderately rapid permeabiltiy in the 2C horizon.
USE AND VEGETATION: Doughty soils are used mainly for rangeland. Potential native vegetation is bluebunch wheatgrass, green needlegrass, western wheatgrass, Idaho fescue, and bluegrass.
DISTRIBUTION AND EXTENT: Doughty soils are of moderate extent in central and southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Reconnaissance Soil Survey of Central Montana, 1942.
REMARKS: Soil Interpretations Record: MT0309. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the surface to 14 inches (A and Bt horizons); an argillic horizon from 5 to 14 inches (Bt horizon); calcic horizons from 14 to 60 inches (Bk1, Bk2, 2Ck1, 2Ck2 horizons).
Doughty soils have a frigid temperature regime and an ustic moisture regime.