LOCATION WORK MT+WY
Established Series
Rev. NRS-JAL-EMM
03/2014
WORK SERIES
The Work series consists of very deep, well drained soils that formed in alluvium or colluvium. Work soils are on alluvial fans, stream terraces, relict stream terraces, plains, and hills. Slopes are 0 to 60 percent. The mean annual precipitation is about 14 inches, and the mean annual air temperature is about 44 degrees F.
TAXONOMIC CLASS: Fine, smectitic, frigid Typic Argiustolls
TYPICAL PEDON: Work clay loam, cultivated (colors are for dry soil unless otherwise noted).
Ap--0 to 6 inches; grayish brown (10YR 5/2) clay loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; slightly hard, very friable, slightly sticky and moderately plastic; many fine roots; common unstained silt and sand grains; slightly alkaline; clear smooth boundary. (3 to 10 inches thick)
Bt--6 to 13 inches; brown (10YR 4/3) clay, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to strong medium and fine blocky; very hard, firm, moderately sticky and moderately plastic; many fine and very fine roots; common fine and very fine pores; continuous faint clay films; slightly alkaline; clear boundary. (6 to 24 inches thick)
Btk--13 to 19 inches; grayish brown (2.5Y 5/2) clay loam, dark grayish brown (2.5Y 4/2) moist; moderate medium prismatic structure parting to weak medium blocky; hard, friable, moderately sticky and moderately plastic; common fine and very fine roots; common fine and very fine pores; common faint clay films on vertical faces of peds; 5 percent gravel; common masses of lime; strongly effervescent; moderately alkaline; gradual wavy boundary. (0 to 16 inches thick)
Bk1--19 to 29 inches; grayish brown (2.5Y 5/2) clay loam, dark grayish brown (2.5Y 4/2) moist; weak coarse prismatic structure; hard, friable, moderately sticky and moderately plastic; few to common fine roots; many fine and very fine pores; 10 percent gravel; many masses of lime; continuous distinct lime coats on gravel; violently effervescent; moderately alkaline; gradual wavy boundary.
Bk2--29 to 42 inches; brown (10YR 5/3) gravelly clay loam, brown (10YR 4/3) moist; massive; hard, friable, moderately sticky and slightly plastic; few very fine roots; many fine pores; 20 percent gravel; few masses of lime; continuous distinct lime coats on underside of gravel; strongly effervescent; moderately alkaline; gradual wavy boundary.
BCk--42 to 60 inches; pale brown (10YR 6/3) gravelly clay loam, brown (10YR 4/3) moist; massive; hard, friable, moderately sticky and slightly plastic; 30 percent gravel; disseminated lime; continuous distinct lime coats on underside of gravel; strongly effervescent; moderately alkaline.
TYPE LOCATION: Blaine County, Montana; 1,600 feet east and 500 feet south of the NW corner of sec. 24, T. 27 N., R. 20 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 38 to 47 degrees F.
Moisture control section - between 4 and 12 inches, and are not dry in all parts from July 15 through August.
Mollic epipedon thickness - 7 to 16 inches.
Depth to Bk horizon - 11 to 30 inches.
Some pedons have a Bky horizon.
Surface stones or boulders - 0 to 20 percent
Ap horizon
Hue: 7.5YR, 10YR or 2.5Y
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 1 to 3, dry or moist
Texture: loam, clay loam, sandy clay loam, silt loam
Clay content: 15 to 40 percent
Rock fragments: 0 to 60 percent--0 to 30 percent stones or cobbles, 0 to 30 percent gravel or channers
Reaction: pH 6.1 to 7.8
Bt horizon
Hue: 7.5YR, 10YR or 2.5Y
Value: 4 or 5 dry; 2, 3, or 4 moist
Chroma: 2 to 4, dry or moist
Texture: clay loam, clay, silty clay
Clay content: 35 to 50 percent, and more than 15 percent fine sand and coarser
Rock fragments: 0 to 30 percent--0 to 15 percent cobbles or stones, 0 to 15 percent gravel
Reaction: pH 6.6 to 7.8
Btk horizon
Hue: 7.5YR, 10YR or 2.5Y
Value: 5 to 7 dry, 4 or 5 moist
Chroma: 2 to 4, dry or moist
Texture: clay or clay loam
Clay content: 30 to 45 percent
Rock fragments: 0 to 45 percent--0 to 25 percent cobbles or stones, 0 to 20 percent gravel
Calcium carbonate equivalent: 3 to 15 percent
Reaction: pH 6.6 to 8.4
Bk, BCk horizons
Hue: 7.5YR, 10YR, 2.5Y or 5Y
Value: 5 to 7 dry; 3 to 6 moist
Chroma: 2 to 4, dry or moist
Texture: loam or clay loam
Clay content: 15 to 40 percent
Rock fragments: 0 to 45 percent--0 to 20 percent cobbles, 0 to 30 percent gravel, 0 to 5 percent stones
Calcium carbonate equivalent: 3 to 15 percent
Reaction: pH 7.4 to 8.4
COMPETING SERIES:
Absarokee (MT) - has a paralithic contact at 20 to 40 inches.
Acree (CO) - hues of 5YR or redder in the argillic horizon; a discontinuity in the argillic horizon.
Barela (NM) - has a lithic contact of basalt at 40 to 60 inches.
Capillo (NM) - does not have horizons of secondary carbonate accumulation.
Dandrea (AZ) - has a paralithic contact at 40 to 60 inches.
Delson (CO) - is noncalcareous throughout the profile.
Ekah (MT) - has a calcic horizon.
Herm (CO) - is noncalcareous throughout the profile.
Morapos (CO) - is dry in all parts of the moisture control section for 45 consecutive days after the middle of July.
Moreno (NM) - does not have horizons of secondary carbonate accumulation.
Nortez (CO) - bedrock between depths of 20 to 40 inches.
Pramiss (CO) - bedrock between depths of 20 to 40 inches.
Ricot (CO) - hues of 5YR or redder in the argillic horizon; a discontinuity in the argillic horizon.
Tamaneen (MT) - has over 35 percent coarse fragments between the depths of 20 and 40 inches.
Tukunnik (UT) - has secondary carbonates deeper than 30 inches.
Zau (CO) - has a paralithic contact at 20 to 40 inches; does not have horizons of secondary carbonate accumulation.
GEOGRAPHIC SETTING:
Landform - relict stream terraces, stream terraces, hills, alluvial fans, plains, and moraines.
Elevation - 2,800 to 6,400 feet.
Slope - 0 to 60 percent.
Parent material - alluvium, colluvium or glacial outwash.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 13 to 20 inches.
Mean annual air temperature - 36 to 45 degrees F.
Frost-free period - 70 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.
USE AND VEGETATION: Work soils are used for non-irrigated and irrigated crops. Major crops are wheat, barley, alfalfa, and mixed hay. Some areas are also used for range. Native vegetation is mainly rough fescue, bluebunch wheatgrass, needleandthread, green needlegrass, Idaho fescue, forbs, and shrubs.
DISTRIBUTION AND EXTENT: The Work series is extensive in Montana and Wyoming. MLRAs 43B, 44B, 46, 48A, 58A, 62.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Carbon County, Montana, 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are: Mollic epipedon - the zone from the soil surface to 13 inches (Ap, Bt horizons);
Argillic horizon - the zone from 6 to 13 inches which is also the particle-size control section (Bt horizons);
Horizons of secondary carbonate accumulation - from 13 to 60 inches (Btk, Bk1, Bk2k, BCk horizons).
Soil interpretation record: MT0137, MT0782, MT0142.
Work soils have a frigid temperature regime and an ustic moisture regime.
National Cooperative Soil Survey
U.S.A.