LOCATION FLOTT MTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Haplustolls
TYPICAL PEDON: Flott gravelly loam, forested (colors are for dry soil unless other noted).
Oe--0 to 2 inches; intermediately decomposed needles and twigs.
A1--2 to 10 inches; dark grayish brown (10YR 4/2) gravelly loam, very dark gray (10YR 3/1) moist; moderate medium granular structure; soft, very friable, slightly sticky and slightly plastic, many fine and medium roots; many very fine interstitial pores; 5 percent cobbles and 20 percent pebbles; slightly acid (pH 6.4); clear wavy boundary. (6 to 10 inches thick)
A2--10 to 12 inches; dark grayish brown (10YR 4/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate medium granular structure; soft, very friable, slightly sticky and slightly plastic; many fine and medium roots; many very fine interstitial pores; 5 percent cobbles and 20 percent pebbles; slightly acid (pH 6.2); abrupt wavy boundary. (2 to 6 inches thick)
E--12 to 20 inches; brown (10YR 5/3) very gravelly loam, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many fine and common medium and coarse roots; common fine interstitial pores; 5 percent cobbles and 50 percent pebbles; slightly acid (pH 6.4); clear wavy boundary. (2 to 10 inches thick)
E/Bw--20 to 25 inches; E part (55 percent) brown (10YR 5/3) very gravelly loam, dark yellowish brown (10YR 4/4) moist; B part (45 percent) light olive brown (2.5Y 5/4) very gravelly loam, olive brown (2.5Y 4/4) moist; weak medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many fine roots and common medium and coarse roots; common fine interstitial pores; 10 percent cobbles and 45 percent pebbles; neutral (pH 7.0); clear wavy boundary. (3 to 6 inches thick)
Bk1--25 to 46 inches; pale yellow (2.5Y 8/2) very gravelly loam, light yellowish brown (2.5Y 6/4) moist; massive; soft very friable, slightly sticky and slightly plastic; few fine roots; 10 percent cobbles and 45 percent pebbles; disseminated lime; violently effervescent; moderately alkaline (pH 8.2); gradual smooth boundary. (10 to 25 inches thick)
Bk2--46 to 60 inches; pale yellow (2.5Y 7/4) very gravelly loam, light olive brown (2.5Y 5/4) moist; massive; soft, very friable, slightly sticky and slightly plastic; 10 percent cobbles and 45 percent pebbles; disseminated lime; violently effervescent; moderately alkaline (pH 8.2).
TYPE LOCATION: Lake County, Montana; 800 feet south and 1,800 feet east of the NW corner of sec. 6, T. 17 N., T. 19 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 42 to 47 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 8 to 16 inches.
Control section - 18 to 30 percent clay and 35 to 60 percent rock fragments.
Depth to k horizon - 15 to 30 inches.
A horizon - Value: 3, 4, or 5 dry; 2 or 3 moist
Chroma: 2 dry; 1 moist
Texture: loam or silt loam
Clay content: 10 to 27 percent
Rock fragments: 15 to 60 percent--0 to 15 percent cobbles and stones, 15 to 45 percent pebbles
Reaction: pH 6.1 to 7.3
E horizon - Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2, 3, or 4
Texture: loam or silt loam
Clay content: 10 to 27 percent
Rock fragments: 35 to 60 percent--0 to 15 percent cobbles and stones, 35 to 45 percent pebbles
Reaction: pH 6.1 to 7.3
E/Bw horizon - Hue: B part 10YR or 2.5Y; E part 10YR or 2.5Y
Value: E part 5 or 6, B part 4 or 5 dry; E part 4 or 5, B part 4 or 5 moist
Chroma: E part 3 or 4; B part 4 or 6
Texture: loam, silt loam, or clay loam
Clay content: 18 to 30 percent
Rock fragments: 35 to 60 percent--0 to 15 percent cobbles and stones, 35 to 45 percent pebbles
Reaction: pH 6.6 to 7.8
Some pedons have a B/E horizon instead of an E/B horizon.
Bk horizons - Hue: 10YR or 2.5Y
Value: 6, 7, or 8 dry; 4, 5, or 6 moist
Chroma: 2, 3, or 4
Texture: loam, silt loam, clay loam
Clay content: 18 to 30 percent
Rock fragments: 35 to 60 percent--0 to 15 percent cobbles and stones, 35 to 45 percent pebbles
Calcium carbonate equivalent: 15 to 40 percent
Reaction: pH 7.9 to 8.4
COMPETING SERIES:
Finleypoint (MT) - do not have a calcic horizon.
Kutler (CO) - have a paralithic contact at 20 to 40 inches; do not have horizons of secondary carbonate accumulation.
Perma (MT) - do not have horizons of secondary carbonate accumulation; have more than 60 percent coarse fragments below 30 inches.
Renegade (UT) - do not have horizons of secondary carbonate accumulation; have a paralithic contact at 40 to 60 inches.
Sandia (NM) - do not have horizons of secondary carbonate accumulation; have a lithic contact at 40 to 60 inches.
Slimbutte (SD) - have cambic horizons.
Subwell (MT) - have cambic horizons; have a lithologic discontinuity.
Towave (UT) - does not have a calcic horizon.
Veatch (CO) - have a lithic contact at 20 to 40 inches.
Vigilante (MT) - do not have horizons of secondary carbonate accumulation; have a lithic contact at 40 to 60 inches.
Wanagan (ND) - have a lithologic discontinuity at 14 to 28 inches.
Wimper (MT) - have a cambic horizon.
Walstead (MT) - have a cambic horizon; do not have an albic horizon or a mixed E/Bw horizon.
GEOGRAPHIC SETTING:
Landform - moraines, hills, and mountains.
Elevation - 2,900 to 4,500 feet.
Slopes - 0 to 60 percent.
Parent material - till or colluvium derived from limestone or calcareous argillite.
Climate - long, cold winters; moist springs; warm, dry summers.
Mean annual precipitation - 18 to 22 inches, much of which falls as snow and as spring rain.
Mean annual temperature - 40 to 44 degrees F.
Frost-free period - 90 to 105 days.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Flott soils are used mainly for woodland and understory grazing and some cherry orchards near Flathead Lake. The potential native vegetation is Douglas fir and ponderosa pine with an understory of pinegrass, common snowberry, mallow ninebark, and elk sedge.
DISTRIBUTION AND EXTENT: Flott soils are of moderate extent in northwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Lake County, Montana, 1991; proposed in Lake County, Montana, 1987. Flott is a coined name.
REMARKS: Soil Interpretation Record: MT1043. Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from 2 to 12 inches (A1 and A2 horizons); a mixed horizon from 20 to 25 inches (E/Bw horizon); calcic horizons from 25 to 60 inches (Bk horizons); a particle-size control section from 10 to 40 inches below the mineral soil surface (E, E/Bw, Bk1 horizons). Flott soils have a frigid temperature regime and an ustic moisture regime.