LOCATION ADEL                    MT+CO ID NM UT WY

Established Series
Rev. DES-CBR-RJS
04/2015

ADEL SERIES

The Adel series consists of very deep, well drained soils that formed in alluvium, colluvium or slide deposits. These soils are on alluvial fans, fan remnants, mountain slopes, hills, landslides, stream terraces, drainageways and swales. Slopes are 0 to 65 percent. Mean annual precipitation is about 25 inches, and mean annual temperature is about 40 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive Pachic Haplocryolls

TYPICAL PEDON: Adel loam, grassland (colors are for dry soil unless otherwise noted).

A1--0 to 13 inches; dark gray (10YR 4/1) loam, black (10YR 2/1) moist; moderate medium and fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine and very fine roots; many very interstitial pores; many worm casts; slightly acid (pH 6.1); gradual wavy boundary.

A2--13 to 31 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; weak medium and fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine and very fine roots; many very fine and fine pores; many worm casts; slightly acid (pH 6.1); diffuse wavy boundary.

A3--31 to 38 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure parting to moderate fine and very fine subangular blocky; slightly hard, very friable, slightly sticky and slightly plastic; common fine and very fine roots; many fine and very fine pores; neutral (pH 7.0); gradual wavy boundary. (Combined thickness of A horizons is 6 to 50 inches)

Bw--38 to 60 inches: brown (10YR 5/3) channery loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure parting to moderate very fine subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine pores; 20 percent angular gravel, 5 percent angular cobbles; neutral (pH 7.0).

TYPE LOCATION: Fergus County, Montana; 1,050 feet west and 450 feet south of the NE corner of sec. 9, T. 13 N., R. 18 E.

RANGE IN CHARACTERISTICS:
Soil temperature - 35 to 46 degrees F.
Soil temperature, summer - 52 to 59 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 16 to 60 inches.

A1 horizon
Hue: 2.5Y or 10YR; dry or moist
Value: 2 to 4, or 5 dry; 2 or 3 moist
Chroma: 1 or 2; dry or moist
Texture: loam, silt loam, clay loam, silty clay loam
Clay content: 15 to 35 percent
Rock fragments: 0 to 35 percent--0 to 30 percent gravel, 0 to 5 percent stones and cobbles
Reaction: pH 6.1 to 7.3

A2 horizon
Hue: 2.5Y or 10YR; dry or moist
Value: 3 to 5 dry; 2 or 3 moist
Chroma: 1 to 3; dry or moist
Texture: loam, silt loam or clay loam
Clay content: 18 to 30 percent
Rock fragments: 0 to 35 percent--0 to 30 percent gravel, 0 to 5 percent stones and cobbles
Reaction: pH 6.1 to 7.8

A3 horizon
Hue: 2.5Y or 10YR; dry or moist
Value: 3 to 5 dry; 2 to 4 moist
Chroma: 1 to 3; dry or moist
Texture: loam, silt loam or clay loam
Clay content: 18 to 30 percent
Rock fragments: 0 to 35 percent--0 to 30 percent gravel, 0 to 5 percent stones and cobbles
Reaction: pH 6.1 to 7.8

Bw horizon
Hue: 2.5Y or 10YR; dry or moist
Value: 4 to 7 dry; 2 to 5 moist
Chroma: 1 to 4; dry or moist
Texture: loam, clay loam, silt loam, or silty clay loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 35 percent--0 to 30 percent gravel, 0 to 10 percent stones and cobbles
Reaction: pH 6.1 to 7.8

Some pedons have a BC or C horizon that has a dry value of 4 to 6 and a moist value of 3 to 5 and hues of 2.5Y or 10YR. Textures are similar to the Bw horizon.

COMPETING SERIES:
Argee (NV) - is moderately deep to paralithic contact
Bullbasin (CO) - is deep to lithic contact
Duff (NV) - is deep to lithic contact
Hackwood (NV) - have a lithologic discontinuity
Houlihan (MT) - have an ustic moisture regime
Lamphier (CO) - have hues redder than 10YR
Leavittville (WY) - have secondary calcium carbonate accumulation
Lespate (CO) - is moderately deep to lithic contact
Ohbejoyful (CO) - contains rock fragments consisting of andesite, rhyolite, breccia or tuff
Osmund (WY) - have secondary calcium carbonate accumulation
Pavohroo (ID) - have a cambic horizon
Rhone (CO) - is deep to lithic contact
Secondset (CO) - is moderately deep to lithic contact
Strickland (NV) - is moderately deep to lithic contact
Taterheap (CO) - have a lithologic discontinuity
Winevada (CO) - is moderately deep to lithic contact

GEOGRAPHIC SETTING:
Landform - alluvial fans, fan remnants, mountain slopes, hills, landslides, stream terraces, drainageways and swales
Elevation - 4,500 to 8,500 feet in Montana; 7,800 to 11,300 feet in Colorado
Slope - 0 to 65 percent
Parent material - alluvium, colluvium or slide deposits
Climate - cold with long, cold winters; moist, cool springs; short, cool summers
Mean annual precipitation - 14 to 30 inches in Montana; 15 to 35 inches in Colorado; 20 to 30 inches in Wyoming
Mean annual temperature - 34 to 44 degrees F.
Frost-free period - 30 to 70 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cheadle and Teton series. Cheadle soils are shallow to bedrock, are loamy-skeletal, and are not pachic. Teton soils are moderately deep to bedrock and are not pachic. These soils are on more convex positions.

DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.

USE AND VEGETATION: Used as dry and irrigated cropland and as rangeland. Potential native vegetation is bluebunch wheatgrass, Columbia needlegrass, Idaho fescue, rough fescue, bluegrass, lupine, shrubby cinquefoil, big sagebrush, and sagewort. Some areas have an overstory of aspen.

DISTRIBUTION AND EXTENT: Northern Rocky Mountain valleys in Montana and western Colorado, and adjacent portions of Idaho and Wyoming. Adel soils are of moderate extent. MLRA 43B, 44B, 46 and 48A.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.

SERIES ESTABLISHED: Reconnaissance Soil Survey of central Montana, 1946.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 60 inches (A1, A2, A3 and Bw horizons)
Particle-size control section from 10 to 40 inches (part of A1, A2, A3, and part of Bw horizon)

Adel soils have a cryic temperature regime and a udic moisture regime. There are significant acres of soils mapped as Adel that have an ustic soil moisture regime. These areas should be investigated in the future to determine if they should be correlated to the Houlihan series (ustic counterpart to Adel).

Additional Information
Soil Interpretation Records: MT0075, MT0692, MT0831, MT1038.

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National Cooperative Soil Survey
U.S.A.