LOCATION ALTYN MT
Tentative Series
Rev. PHO-JMS-RJS
05/2017
ALTYN SERIES
The Altyn series consists of very deep, excessively drained soils that formed in volcanic ash influenced alluvium, colluvium or till derived from metasedimentary sources. These soils are on alluvial fans, colluvial aprons and mountain slopes. Slopes are 4 to 35 percent. Mean annual precipitation is about 1,025 mm and mean annual air temperature is about 4.0 degrees C.
TAXONOMIC CLASS: Sandy-skeletal, mixed Vitrandic Haplocryepts
TYPICAL PEDON: Altyn gravelly ashy loam, in coniferous forest at 1,370 meters elevation (colors are for dry soil unless otherwise noted).
A--0 to 12 cm; pale brown (10YR 6/3) gravelly ashy loam, dark brown (10YR 3/3) moist; weak very fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine, and common medium and coarse roots; many very fine irregular pores; 30 percent gravel; slightly acid (pH 6.2); clear smooth boundary.
Bw1--12 to 25 cm; light yellowish brown (10YR 6/4) gravelly ashy loam, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; many very fine and fine, and common medium and coarse roots; common very fine irregular pores; 25 percent gravel; slightly acid (pH 6.2); clear smooth boundary.
2Bw2--25 to 41 cm; very pale brown (10YR 7/3) very gravelly sandy loam, brown (10YR 5/3) moist; weak fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine, fine and medium, and few coarse roots; common very fine irregular pores; 35 percent gravel; slightly acid (pH 6.4); clear wavy boundary.
2C1--41 to 62 cm; light gray (10YR 7/2) extremely gravelly loamy sand, yellowish brown (10YR 5/4) moist; single grain; loose, nonsticky and nonplastic; common very fine and fine, and few medium and coarse roots; common very fine interstitial pores; 70 percent gravel; moderately acid (pH 6.0); clear wavy boundary.
2C2--62 to 152 cm; very pale brown (10YR 7/3) extremely gravelly coarse sand moist; brown (10YR 5/3) moist; single grain; loose, nonsticky and nonplastic; few very fine and fine roots; common very fine interstitial pores; 70 percent gravel; slightly acid (pH 6.2).
TYPE LOCATION: Glacier County, Montana; located about 612 meters north and 415 meters east of the northeast corner of section 14, T. 33 N., R. 20 W.; Huckleberry Mountain topographic quadrangle; Latitude - 48 degrees, 37 minutes, 21 seconds north; Longitude - 114 degrees, 7 minutes, 58 seconds west.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 2.5 to 6.0 degrees C.
Vitrandic soil properties thickness - 18 to 35 cm
Depth to top of cambic - 3 to 12 cm
Particle-size control section - averages 8 to 18 percent clay
O horizons (where present)
Thickness: 0 to 5 cm
A or E (where present) horizons
Hue: 10YR or 7.5YR dry or moist
Value: 4 to 6 dry, 2 to 4 moist
Chroma: 1 to 4 dry and moist
Texture, less than 2mm fraction: ashy loam, ashy sandy loam
Clay content: 8 to 18 percent
Rock fragments: 15 to 45 percent--15 to 45 percent gravel; 0 to 10 percent cobbles
Reaction: pH 5.4 to 6.5
Thickness: 3 to 12 cm
Bw1 horizon
Hue: 10YR or 7.5YR dry or moist
Value: 4 to 7 dry, 3 to 5 moist
Chroma: 1 to 4 dry and moist
Texture, less than 2mm fraction: ashy loam, ashy sandy loam
Clay content: 8 to 18 percent
Rock fragments: 15 to 55 percent--15 to 55 percent gravel; 0 to 10 percent cobbles
Reaction: pH 5.4 to 6.5
Thickness: 10 to 30 cm
2Bw2 horizon (where present)
Hue: 10YR or 7.5YR dry or moist
Value: 4 to 7 dry, 3 to 5 moist
Chroma: 1 to 4 dry and moist
Texture, less than 2mm fraction: loam, sandy loam
Clay content: 8 to 18 percent
Rock fragments: 35 to 75 percent--35 to 75 percent gravel; 0 to 20 percent cobbles
Reaction: pH 6.0 to 7.0
Thickness: 0 to 16 cm
2C1, 2C2 horizons:
Hue: 10YR or 7.5YR dry or moist
Value: 6 or 7 dry, 4 to 6 moist
Chroma: 1 to 4 dry or moist
Texture, less than 2mm fraction: loamy sand, sand, coarse sand
Clay content: 0 to 6 percent
Rock fragments: 60 to 80 percent--40 to 80 percent gravel; 0 to 20 percent cobbles
Reaction: pH 6.0 to 7.0
Thickness: greater than 85 cm
COMPETING SERIES: These are no competing series.
GEOGRAPHIC SETTING:
Landform: alluvial fans, colluvial aprons and mountain slopes
Elevation: 1,000 to 1,740 meters
Slope: 4 to 35 percent
Parent material: volcanic ash influenced alluvium, colluvium or till derived from metasedimentary sources
Mean annual precipitation: 825 to 1,900 mm
Mean annual air temperature: 2.0 to 5.0 degrees C.
Frost-free period: 50 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Excessively drained; 5 to 15 um/sec in the surface layer and 15 to 150 um/sec below.
USE AND VEGETATION: Recreation, woodland and wildlife habitat. The vegetation is mainly subalpine fir and spruce with thinleaf huckleberry, thimbleberry, rocky mountain maple, mountain ash, spirea, heartleaf arnica, queen's cup bead lily, and other miscellaneous forbs and grasses in the understory.
DISTRIBUTION AND EXTENT: These soils are of small extent in northwestern Montana. MLRAs - 43A and 43B.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana.
SERIES PROPOSED: Glacier National Park area in Glacier County, Montana, 2015. The series name is derived from a local landmark.
REMARKS: Diagnostic features recognized in this pedon are:
Vitrandic subgroup feature - 0 to 25 cm (A, Bw1 horizons)
Cambic horizon - 12 to 41 inches (Bw1, 2Bw2 horizons)
Particle-size control section - 25 to 100 cm (2Bw2, 2C1, part of the 2C2 horizons)
Altyn soils have a cryic temperature regime and an udic moisture regime.
Taxonomic version: Twelfth Edition, 2014
National Cooperative Soil Survey
U.S.A.