LOCATION SCALPLOCK MT
Tentative Series
Rev. PHO-JMS-RJS
03/2017
SCALPLOCK SERIES
The Scalplock series consists of shallow, well drained soils that formed in colluvium over residuum derived from metasedimentary rock. These soils are on mountain slopes and cirque headwalls. Slopes are 8 to 80 percent. Mean annual precipitation is about 1,825 mm and mean annual air temperature is about 2.0 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Lithic Haplocryolls
TYPICAL PEDON: Scapegoat gravelly silt loam, grassland. This profile was described on an 8 percent slope at 2,128 meters in elevation. (colors are for dry soil unless otherwise noted)
A--0 to 8 cm; dark grayish brown (10YR 4/2) gravelly silt loam, very dark brown (10YR 2/2) moist; weak very fine granular structure; slightly hard, friable, nonsticky and nonplastic; common very fine, fine and medium roots; common very fine and fine irregular pores; 25 percent gravel; moderately acid (pH 5.8); clear smooth boundary.
Bw1--8 to 19 cm; dark grayish brown (10YR 4/2) very gravelly silt loam, very dark gray (10YR 3/1) moist; weak fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine and few medium roots; common very fine irregular pores; 35 percent gravel; slightly acid (pH 6.2); clear smooth boundary.
Bw2--19 to 38 cm; brown (10YR 4/3) very gravelly loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and nonplastic; common very fine and few medium roots; common very fine irregular pores; 55 percent gravel; slightly acid (pH 6.4); abrupt smooth boundary.
R--38 cm; fractured hard metasedimentary bedrock.
TYPE LOCATION: Glacier County, Montana; 305 meters south and 95 meters east of the NW corner of sec. 19, T. 35 N., R. 16 W.; Ahern Pass topographic quadrangle; Latitude - 48 degrees, 46 minutes, 51 seconds north; Longitude - 113 degrees, 45 minutes, 37 seconds west, NAD 1983.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature -- 1.0 to 5.0 degrees C.
Mollic epipedon thickness -- 18 to 40 cm
Depth to a lithic contact -- 25 to 49 cm
A horizon
Hue: 2.5Y, 10YR or 7.5YR dry or moist
Value: 3 to 5 dry; 2 or 3 moist
Chroma: 1 to 3 dry or moist
Texture (less than 2 mm fraction): loam or silt loam
Clay content: 10 to 20 percent
Rock fragments: 25 to 60 percent--25 to 60 percent gravel and/or channers, 0 to 10 percent cobbles, 0 to 10 percent flagstones, 0 to 5 percent stones
Reaction: pH 5.8 to 7.0
Thickness: 8 to 25 cm
Bw1, Bw2 horizons
Hue: 10YR, 7.5YR or 5YR dry or moist
Value: 3 to 6 dry; 2 to 5 moist
Chroma: 1 to 3 dry or moist
Texture (less than 2 mm fraction): loam, sandy loam or silt loam
Clay content: 10 to 18 percent
Rock fragments: 35 to 80 percent--35 to 70 percent gravel and/or channers, 0 to 10 percent cobbles, 0 to 10 percent flagstones, 0 to 5 percent stones
Reaction: pH 6.1 to 7.0
Thickness (Bw1, Bw2 combined): 15 to 40 cm thick
COMPETING SERIES:
Arrowpeak (MT) -- have a mean annual precipitation less than 900 mm
Betemer (CO) -- have an ustic moisture regime
Catlinsprings (MT) -- have an ustic moisture regime
Cheadle (MT) -- have secondary calcium carbonate accumulation
Chokecherry (ID) -- have a xeric moisture regime
Clamp (OR) -- have a xeric moisture regime
Dalys (MT) -- are very shallow to lithic contact
Dollarhide (ID) -- have a xeric moisture regime
Eyre (CO) -- have a mean annual precipitation less than 900 mm
Irigul (WY) -- have an ustic moisture regime
Irson (WY) -- do not have Bw horizons
Jonlake (NV) -- have a xeric moisture regime
Labshaft (NV) -- have a xeric moisture regime
Mccadden (UT) -- have secondary calcium carbonate accumulation
Milling (WA) - have a xeric moisture regime
Poin (MT) -- have an ustic moisture regime
Rogert (CO) -- have an ustic moisture regime
Schwacheim (CO) -- do not have Bw horizons
Starley (WY) -- have secondary calcium carbonate accumulation
Topeki (NV) -- have a xeric moisture regime
Trump (CO) -- have an ustic moisture regime
Udel (NV) -- are very shallow to a lithic contact
GEOGRAPHIC SETTING:
Landform -- mountain slopes and cirque headwalls
Elevation -- 1,600 to 2,600 meters
Slope -- 8 to 80 percent
Parent material -- colluvium over residuum derived from metasedimentary rock
Climate -- long, cold winters; moist springs; short warm summers
Mean annual precipitation -- 1,000 to 2,500 mm
Mean annual air temperature -- 0.0 to 4.0 degrees C.
Frost-free period -- 20 to 50 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained and moderate permeability (10 to 100 um/sec).
USE AND VEGETATION: Scalplock soils are used mainly for recreation and wildlife habitat. Vegetation is dominantly by an overstory of subalpine fir, and the understory is primarily pinegrass, arrowleaf groundsel, Hitchcock's woodrush, and leafy aster.
DISTRIBUTION AND EXTENT: Scalplock soils are of small extent in northwestern Montana. MLRA 43A and 43B.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana.
SERIES PROPOSED: Glacier National Park area in Glacier County, Montana, 2015.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon -- 0 to 38 cm (A, Bw1, Bw2 horizons)
Lithic contact -- 38 cm (R horizon)
Particle-size control section -- 25 to 38 cm (part of Bw2 horizon)
Scalplock soils have a cryic temperature regime and an udic moisture regime.
National Cooperative Soil Survey
U.S.A.