LOCATION LAKEMOUNTAIN WY
Tentative Series
IRD DJP/CBR
03/2018
LAKEMOUNTAIN SERIES
The Lakemountain series consists of very deep, well drained soils that formed in slope alluvium and colluvium derived from quartzite. These soils are on ridges , hillslopes and mountain slopes. Slopes are 5 to 25 percent. Mean annual precipitation is about 550 mm, and mean annual air temperature is about 0.8 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Typic Argicryolls
TYPICAL PEDON: Lakemountain loam, in forestland (colors are for dry soil unless otherwise noted).
A--0 to 6 cm; very dark gray (5YR 3/1) loam, black (5YR 2.5/1) moist; moderate fine granular structure; soft, very friable, slightly sticky, slightly plastic; many very fine roots throughout; many very fine interstitial pores; 5 percent gravel; slightly acid (pH 6.1); clear smooth boundary. (5 to 30 cm thick)
BA--6 to 25 cm; reddish brown (5YR 4/3) gravelly clay loam, dark reddish brown (5YR 3/3) moist; moderate fine subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; many fine roots throughout; many very fine vesicular pores; 20 percent gravel and 5 percent cobbles; slightly acid (pH 6.4); gradual smooth boundary. (0 to 22 cm thick)
Bt--25 to 67 cm; reddish brown (2.5YR 4/4) very gravelly clay loam, dark reddish brown (2.5YR 3/4) moist; moderate fine subangular blocky structure; moderately hard, firm, moderately sticky, moderately plastic; many very fine and medium roots throughout; many very fine tubular pores; 30 percent gravel and 5 percent cobbles; 20 percent faint clay films on all faces of peds; slightly alkaline (pH 7.5); gradual smooth boundary. (38 to 44 cm thick)
Btk1-- 67 to 107 cm; reddish brown (2.5YR 4/4) very gravelly clay loam, dark reddish brown (2.5YR 3/4) moist; moderate medium subangular blocky structure; moderately hard, firm, moderately sticky, moderately plastic; many very fine and medium roots throughout; many very fine tubular pores; 30 percent gravel and 5 percent cobbles; 15 percent calcium carbonate coats on bottom surfaces of rock fragments and 20 percent faint clay films on all faces of peds; slightly effervescent; slightly alkaline (pH 7.6); clear wavy boundary.
Btk2-- 107 to 150 cm; dark yellowish brown (10YR 4/4) cobbly clay, dark yellowish brown (10YR 3/4) moist; moderate fine angular blocky structure; hard, very firm, very sticky, very plastic; common very fine and medium roots throughout; many very fine vesicular pores; 10 percent gravel and 10 percent cobbles; 20 percent calcium carbonate coats on bottom surfaces of rock fragments and 35 percent faint clay films on all faces of peds; slightly effervescent; slightly alkaline (pH 7.6; clear wavy boundary. (combined thickness of Btk1 and Btk2 horizons is 78 to 88 cm)
Btk3-- 150 to 200 cm; yellowish brown (10YR 5/4) cobbly clay, dark yellowish brown (10YR 4/4) moist; moderate fine angular blocky structure; hard, very firm, very sticky, very plastic; many very fine vesicular pores; 10 percent gravel and 10 percent cobbles; 15 percent calcium carbonate coats on bottom surfaces of rock fragments and 35 percent faint clay films on all faces of peds; slightly effervescent; slightly alkaline (pH 7.6).
TYPE LOCATION: Sublette County, Wyoming; USGS Lake Mountain, Wyoming, topographic quadrangle; 42 degrees 21 minutes 16.00 seconds north latitude and 110 degrees 23 minutes 55.75 seconds west longitude, datum WGS84.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature -- 1.0 to 3.1 degrees C.
Mollic epipedon thickness -- 25 to 30 cm
Depth to secondary carbonates -- 60 to 80 cm
Particle-size control section (weighted averages)
Clay content -- 26 to 34 percent
Total rock fragments -- 35 to 45 percent
A horizon
Hue: 2.5YR or 5YR, dry or moist
Value: 3 or 4 dry; 2.5 or 3 moist
Chroma: 1 to 3, dry or moist
Clay content: 14 to 25 percent
Rock fragments: 0 to 10 percent gravel
Reaction: pH 6.1 to 6.5
BA horizon (when present)
Hue: 2.5YR or 5YR, dry or moist
Value: 3 or 4 dry; 2.5 or 3 moist
Chroma: 2 or 3, dry or moist
Texture (less than 2 mm fraction): loam, clay loam
Clay content: 25 to 33 percent
Rock fragments: 20 to 25 percent gravel and 0 to 10 percent cobbles
Reaction: pH 5.6 to 6.0
Bt horizon
Hue: 2.5YR or 5YR, dry or moist
Value: 3 or 4 dry; 2.5 or 3 moist
Chroma: 3 or 4, dry or moist
Texture (less than 2 mm fraction): loam, clay loam
Clay content: 25 to 34 percent
Rock fragments: 35 to 45 percent gravel and 5 to 10 percent cobbles
Reaction: pH 7.2 to 7.5
Btk horizons
Hue: 2.5YR to 10YR, dry or moist
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 3 or 4, dry or moist
Texture (less than 2 mm fraction): clay loam, clay
Clay content: 33 to 52 percent
Rock fragments: 10 to 35 percent gravel and 5 to 10 percent cobbles
Calcium carbonate equivalent: 5 to 10 percent
Reaction: pH 7.6 to 8.0
COMPETING SERIES:
Elkpeak (MT) -- soils do not have secondary calcium carbonates
Elwood (UT) -- soils are moderately deep to lithic contact
Ezbin (ID) -- soils do not have secondary calcium carbonates
Grade (WY) -- soils do not have secondary calcium carbonates
Pohlod (MT) -- soils are moderately deep to lithic contact
Quazar (CO) -- soils do not have secondary calcium carbonates
Tahquats (ID) -- soils do not have secondary calcium carbonates
Wander (CO) -- soils do not have secondary calcium carbonates
GEOGRAPHIC SETTING:
Landform -- ridges, hillslopes and mountain slopes
Elevation -- 2,590 to 2,790 meters
Slope -- 5 to 25 percent
Parent material -- slope alluvium and colluvium derived from quartzite
Climate -- long, cold winters; cool, moist springs; short, cool summers
Relative effective annual precipitation -- 610 to 890 mm with peak periods of precipitation occurring during the spring
Mean annual air temperature -- 0.0 to 2.1 degrees C.
Frost-free period -- 10 to 40 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained, 0.01 to 15.0 um/sec.
USE AND VEGETATION: Lakemountain soils are primarily used for forestland. The potential native vegetation is subalpine fir, aspen, pinegrass, snowberry and mountain big sagebrush.
DISTRIBUTION AND EXTENT: Lakemountain soils are of small extent in southwestern Wyoming. MLRA 43B and 46.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Sublette County, Wyoming, 2018. The name is derived from a local landmark.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon -- 0 to 25 cm (A and BA horizons)
Argillic horizon -- 25 to 200 cm (Bt, Btk1, Btk2, and Btk3 horizons)
Secondary calcium carbonate accumulations -- 67 to 200 cm (Btk1, Btk2, and Btk3 horizons)
Particle-size control section -- 25 to 75 cm (Bt and part of the Btk1 horizons)
Lakemountain soils have a cryic temperature regime and an udic moisture regime.
Taxonomic version: Twelfth edition, 2014
National Cooperative Soil Survey
U.S.A.