LOCATION SKAGGS MT
Established Series
Rev. COC-SHB-EMM
04/2014
SKAGGS SERIES
The Skaggs series consists of moderately deep, well drained soils that formed in colluvium and residuum weathered from limestone, limy shale, or calcareous sandstone. These soils are on hills. Slopes range from 2 to 65 percent. Mean annual precipitation is about 21 inches, and mean annual temperature is about 41 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, carbonatic Calcic Haplocryolls
TYPICAL PEDON: Skaggs loam, in native grass (Colors are for dry soil unless otherwise noted.)
A1--0 to 4 inches, very dark gray (10YR 3/1) loam, black (10YR 2/1) moist; strong very fine granular structure; slightly hard, very friable, slightly sticky, nonplastic; many very fine and fine roots; few limestone fragments; neutral; clear wavy boundary.
A2--4 to 10 inches, very dark gray (10YR 3/1) heavy loam, black (10YR 2/1) moist; weak medium blocky structure parting to moderate fine granular; slightly hard, very friable, slightly sticky, slightly plastic; many very fine and fine roots; many very fine and fine pores; 10 percent limestone fragments; slightly effervescent; slightly alkaline; clear wavy boundary.
Bk1--10 to 21 inches, light brownish gray (10YR 6/2) gravelly clay loam, dark grayish brown (10YR 4/2) moist; strong very fine subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; common very fine and fine roots; many very fine and fine pores; 10 percent limestone cobbles; 30 percent limestone gravel; strongly effervescent; moderately alkaline; clear wavy boundary.
Bk2--21 to 32 inches, light gray (2.5Y 7/2) very stony clay loam, grayish brown (2.5Y 5/2) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; few very fine and fine roots; many very fine and fine pores; 20 percent stones; 25 percent gravel; strongly effervescent; moderately alkaline; gradual wavy boundary.
R--32 inches, light gray (2.5Y 7/2) interbedded limestone and shale, light olive brown (2.5Y 5/4) moist; strongly effervescent; moderately alkaline.
TYPE LOCATION: Cascade County, Montana; 900 feet east and 800 feet north of the southwest corner of the northeast 1/4 of sec. 11, T. 16 N., R. 7 E.
RANGE IN CHARACTERISTICS:
Soil temperature: 40 to 47 degrees F
Depth to bedrock: 20 to 40 inches
Oi horizon present in some pedons.
A horizons
Hue - 10YR or 7.5YR
Value - 3 to 5 dry; 2 or 3 moist
Chroma - 1 or 2, dry or moist
Texture - loam, silt loam, or clay loam
Clay content - 20 to 35 percent
Content of rock fragments - 0 to 25 percent--0 to 15 percent stones or cobbles; 0 to 15 percent gravel
Reaction - pH 6.6 to 8.4
Bk1 horizon
Hue - 7.5YR, 10YR, or 2.5Y
Value - 4 to 6 dry; 4 to 8 moist
Chroma - 2 or 3, dry or moist
Texture - loam or clay loam
Clay content - 20 to 35 percent
Content of rock fragments - 35 to 50 percent--5 to 15 percent stones or cobbles; 30 to 35 percent gravel
Calcium carbonate equivalent: 40 to 60 percent
Reaction - pH 7.9 to 8.4
Bk2 horizon
Hue - 7.5YR, 10YR, or 2.5Y
Value - 4 to 7 dry; 5 to 8 moist
Chroma - 2 or 3, dry or moist
Texture - loam or clay loam
Clay content - 20 to 35 percent
Content of rock fragments - 35 to 50 percent--10 to 20 percent stones or cobbles; 15 to 30 percent gravel
Calcium carbonate equivalent - 40 to 60 percent
Reaction - pH 7.9 to 8.4
COMPETING SERIES:
Hanson (MT) - are very deep
Farlin (MT) - are very deep
GEOGRAPHIC SETTING:
Landform: hills
Elevation: 4,800 to 9,000 feet
Slopes: 2 to 75 percent
Parent material: colluvium and residuum weathered from limestone, limy shale, or calcareous sandstone
Climate: cool subhumid
Mean annual temperature: 37 to 45 degrees F
Mean summer temperature: 55 to 58 degrees F
Mean annual precipitation: 18 to 24 inches
Frost-free period: 50 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability
USE AND VEGETATION: Skaggs soils are used mainly for range, but some areas are used for dryland farming. The potential native vegetation is mainly rough fescue, Richardsons needlegrass, mountain brome, Idaho fescue, forbs, and shrubs.
DISTRIBUTION AND EXTENT: Skaggs soils are of moderate extent on the eastern slopes of the Rocky Mountains in Montana and Wyoming; MLRA 44B, 43B, and 46.
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:
Mollic epipedon - the zone from the surface to 10 inches (A1, A2 horizons)
Calcic horizon - the zone from 10 to 32 inches (Bk1, Bk2 horizons)
Lithic contact - at 32 inches (R horizon)
Particle-size control section - the zone from 10 to 32 inches (Bk1, Bk2 horizons)
Skaggs soils have an ustic moisture regime and a cryic temperature regime.
National Cooperative Soil Survey
U.S.A.