LOCATION SILVERCHIEF MT
Established Series
Rev. BDD-DES-KLS
01/2023
SILVERCHIEF SERIES
The Silverchief series consists of very deep, well drained soils that formed in alluvium and colluvium from mixed rock sources. These soils are on mountains and hills. Slopes are 8 to 60 percent. Mean annual precipitation is about 510 mm, and mean annual air temperature is about 4 degrees C.
TAXONOMIC CLASS: Fine, mixed, superactive, frigid Calcic Haplustalfs
TYPICAL PEDON: Silverchief loam, woodland (colors are for dry soil unless otherwise noted).
Oi--0 to 3 cm; organic mat of needles, leaves, and twigs.
Oe--3 to 8 cm; humus layer.
E--8 to 21 cm; pale brown (10YR 6/3) loam, brown (10YR 5/3) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many fine, medium, and coarse roots; many fine and very fine pores; many unstained silt and sand grains on surface of peds; 5 percent gravel; neutral (pH 6.6); clear smooth boundary. (8 to 15 cm thick)
Bt1--21 to 59 cm; reddish brown (2.5YR 5/4) silty clay, reddish brown (2.5YR 4/4) moist; moderate medium prismatic structure parting to strong fine and medium subangular blocky; very hard, firm, moderately sticky and moderately plastic; many fine and medium roots; many fine pores; 10 percent gravel, 5 percent cobbles; common distinct clay films on faces of peds; reddish brown (2.5YR 4/4) strains on faces of peds; neutral (pH 6.7); clear wavy boundary.
Bt2--59 to 77 cm; reddish brown (2.5YR 5/4) gravelly silty clay, reddish brown (2.5YR 4/4) moist; moderate medium and fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common fine and medium roots; many fine pores; 20 percent gravel, 10 percent cobbles; continuous faint clay films on faces of peds; continuous thin coats of lime on underside of smaller gravel, continuous faint crusts of lime on undersides of larger cobbles; slightly alkaline (pH 7.4); gradual clear boundary. (Combined thickness of Bt horizons is 43 to 76 cm.)
Bk--77 to 161 cm; brown (10YR 5/3) very gravelly sandy clay loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and medium roots in upper part grading to few very fine and medium roots in the lower part; common fine pores; 35 percent gravel, 15 percent cobbles; disseminated lime, continuous distinct coating of lime on surface of rock fragments; strongly effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Blaine County, Montana, about 460 meters west and 630 meters south of the NE corner of sec. 9, T 25 N, R 24 E.
RANGE IN CHARACTERISTICS:
Soil moisture control section--between 10 and 30 cm
Mean annual soil temperature--4 to 7 degrees C
Depth to calcic horizon--50 to 100 cm
Surface stones or boulders--0 to 0.1 percent
E horizon
Hue--7.5YR or 10YR
Value--6 or 7 dry; 5 or 6 moist
Chroma--2 through 4
Texture--loam or clay loam
Clay content--20 to 35 percent
Rock fragment content--0 to 30 percent total; gravel--0 to 15 percent; cobbles--0 to 15 percent
Reaction--pH 6.1 to 7.3
Bt horizons
Hue--7.5YR, 10YR, or 2.5Y
Value--5 or 6 dry; 4 or 5 moist
Chroma--3, 4, or 6
Texture--clay, silty clay, or clay loam
Clay content--35 to 60 percent
Rock fragment content--5 to 35 percent total; gravel--5 to 20 percent, cobbles--0 to 15 percent
Reaction--pH 6.1 to 7.8
Bk horizon
Hue--7.5YR, 10YR or 2.5Y
Value--5 through 7 dry; 4 through 6 moist
Chroma--2 through 4
Texture--clay, clay loam, sandy clay loam or loam
Clay content--20 to 45 percent
Rock fragment content--15 to 50 percent total; gravel--15 to 35 percent; cobble--0 to 15 percent
Calcium carbonate equivalent--15 to 35 percent
Reaction--pH 7.4 to 9.0
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Landform--mountains; hills
Elevation--1225 to 1950 meters
Slope--8 to 60 percent
Parent material--colluvium and alluvium from mixed rock sources containing carbonates
Climate--long, cold winters; moist springs; warm summers
Mean annual precipitation--430 to 640 mm
Mean annual air temperature--3 to 6 degrees C
Frost-free period--70 to 100 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability
USE AND VEGETATION: Silverchief soils are used mainly for the production of forest products, summer grazing of livestock, and for grazing by wildlife. Potential native vegetation is mainly lodgepole pine, Douglas-fir, and aspen with an understory of rose, snowberry, common chokecherry, russet buffaloberry, and mahonia.
DISTRIBUTION AND EXTENT: Silverchief soils are of small extent in the mountains of central and southwestern Montana; MLRAs 43B and 46.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Blaine County, Montana, 1976
REMARKS: Soil interpretation record: MT0279
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon--8 to 21 cm (E horizon)
Argillic horizons--21 to 77 cm (Bt1 and Bt2 horizons)
Accumulation of secondary calcium carbonate--77 to 161 cm (Bk horizon)
Particle-size control section--21 to 71 cm (Bt1 horizon and part of the Bt2 horizon)
Silverchief soils have a frigid soil temperature regime and an ustic soil moisture regime.
Converted to metric and O horizons were updated to start at zero. Competing series section was not updated. 01/2023
National Cooperative Soil Survey
U.S.A.