LOCATION ELKNER MT+COEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive Lamellic Haplocryepts
TYPICAL PEDON: Elkner sandy loam, forested (colors are for dry soil unless otherwise noted).
0i--0 to 2 inches; undecomposed and slightly decomposed forest litter.
E1--2 to 9 inches; pale brown (10YR 6/3) sandy loam, brown (10YR 4/3) moist; weak coarse granular structure; soft, very friable, nonsticky and nonplastic; many very fine, fine, and medium roots and few coarse roots; 5 percent gravel; slightly acid (pH 6.2); clear wavy boundary.
E2--9 to 22 inches; light yellowish brown (10YR 6/4) coarse sandy loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, fine, and medium roots and few coarse roots; 5 percent gravel; moderately acid (pH 6.0); clear wavy boundary. (Combined thickness of E horizons is 5 to 22 inches.)
E and Bt--22 to 38 inches; E part (80 percent) is light yellowish brown (10YR 6/4) coarse sandy loam, brown (10YR 4/3) moist; B part (20 percent) is yellowish brown (10YR 5/4) coarse sandy loam lamellae 1/8 to 1/2 inch thick, dark yellowish brown (10YR 4/4) moist; weak coarse subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; 10 percent gravel; moderately acid (pH 5.8); gradual wavy boundary. (10 to 27 inches thick)
BC--38 to 60 inches; light yellowish brown (10YR 6/4) gravelly loamy coarse sand, brown (10YR 4/3) moist, single grain; loose, nonsticky and nonplastic; 20 percent gravel; moderately acid (pH 5.8).
TYPE LOCATION: Missoula County, Montana; 1,000 feet east and 800 feet north of the S 1/4 corner of sec. 34, T. 13, N., R. 14 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 37 to 44 degrees F.
Moisture control section - between 8 and 24 inches.
Depth to BC horizon - 25 to 38 inches
Some pedons have a thin dark colored A horizon.
E horizons - Value: 6 or 7 dry; 3, 4, or 5 moist
Chroma: 2, 3, or 4
Texture: sandy loam or coarse sandy loam
Clay content: 5 to 10 percent
Rock fragments: 0 to 35 percent--0 to 35 percent cobbles, stones, or boulders; 0 to 20 percent gravel
Reaction: pH 5.6 to 6.5
E and Bt or Bt and E horizon - Hue: E part 10YR; B part 10YR or 2.5Y
Value: E part 6 or 7, B part 4 or 5 dry; E part 4 or 5, B part 4 or 5 moist
Chroma: E part 2, 3, or 4; B part 3 or 4
Texture: coarse sandy loam or sandy loam
Clay content: 5 to 10 percent, lamellae has less than 3 percent increase in clay
Rock fragments: 0 to 20 percent--0 to 15 percent cobbles, stones, or boulders; 5 to 20 percent gravel
Reaction: pH 5.6 to 6.5
BC horizon - Hue: 10YR or 2.5Y
Value: 5, 6, or 7 dry; 3, 4, or 5 moist
Chroma: 2, 3, or 4
Texture: loamy coarse sand or coarse sandy loam
Clay content: 0 to 5 percent
Structure: single grain to subangular blocky
Rock fragments: 0 to 35 percent--0 to 20 percent cobbles and stones, 5 to 20 percent gravel
Reaction: pH 5.6 to 7.3
The dark colors are lithochromic.
COMPETING SERIES:
There are no competing series.
GEOGRAPHIC SETTING:
Landform- mountains; hills.
Elevation - 4,500 to 8,600 feet.
Slope - 2 to 70 percent.
Parent material - colluvium derived from granite.
Climate - long, cold winters; moist springs.
Mean annual precipitation - 20 to 30 inches, much of which falls as snow or as spring rain.
Mean annual temperature - 35 to 42 degrees F.
Frost-free period - 30 to 70 days.
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; moderately rapid permeability to a depth of 38 inches and rapid permeability below.
USE AND VEGETATION: Elkner soils are for timber production and watersheds and as wildlife habitat. The native vegetation is subalpine fir, western larch, Douglas fir, and lodgepole pine with an understory of twinflower, common beargrass, and grouse whortleberry.
DISTRIBUTION AND EXTENT: Elkner soils are of small extent in western Montana and in Colorado; MLRA 43.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Missoula County, Montana, 1985.
REMARKS: Soil interpretation record: MT0522, MT1297, MT1277, MT8138. Diagnostic horizons and features recognized in this pedon are: an ochric epipedon from the mineral soil surface to 9 inches (E1 horizon); a cambic horizon from 22 to 38 inches (E and Bt horizons); a particle-size control section from 12 to 42 inches (part of the E2, E and Bt, and part of the BC horizons). Elkner soils have a cryic temperature regime and a udic moisture regime.
The 3/2008 description reflects a change in classification from Coarse-loamy, mixed, superactive Lamellic Eutrocryepts to Coarse-loamy, mixed, superactive Lamellic Haplocryepts due to revision of the cryepts great groups and subgroups. The competing series section was not updated and should be reviewed after all the cryepts have been re-classified.