LOCATION PAPPASCREEK MTEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive Aquic Cumulic Haplocryolls
TYPICAL PEDON: Pappascreek mucky peat, in grassland (colors are for dry soil unless otherwise noted).
Oe--0 to 3 inches; brown (10YR 5/3) mucky peat, very dark grayish brown (10YR 3/2) moist; moderately decomposed herbaceous material and fine grained sediment; massive; slightly hard, very friable, non-sticky and non-plastic; many very fine and fine and common medium roots; moderately acid (pH 5.6); clear smooth boundary. (1 to 4 inches thick)
A1--3 to 18 inches; olive gray (5Y 4/2) loam, very dark gray (5Y 3/1) moist; moderate medium granular structure; slightly hard, friable, moderately sticky and slightly plastic; many very fine and common fine and medium roots; 1 percent fine, subangular gravel, slightly acid (pH 6.4); gradual smooth boundary.
A2--18 to 27 inches; dark grayish brown (2.5Y 4/2) loam with several thin strata of gravelly coarse sand, very dark grayish brown (2.5Y 3/2) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and very fine and few medium roots; few very fine and fine tubular pores; common fine distinct yellowish brown (10YR 5/6) redox concentrations; 10 percent fine subangular gravel; neutral (pH 6.8); gradual wavy boundary. (combined thickness of A horizons is 16 to 32 inches)
Cg--27 to 72 inches; gray (5Y 5/1) sandy loam with strata of gravelly coarse sand, dark gray (5Y 4/1) moist; single grain; loose, non-sticky and non-plastic; few very fine roots; 5 percent fine gravel; neutral (pH 7.0).
TYPE LOCATION: Silver Bow County, Montana; 1,500 feet south and 600 feet east of the northwest corner of sec. 2, T. 3 N., R. 8 W. Butte North topographic quadrangle, UTM zone 12T, 0378662E, 5099844N, NAD 27.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature 36 to 42 degrees F., cryic temperature regime.
Soil moisture control section 8 to 24 inches; dry in some or all parts for 90 or more cumulative days in normal years; not dry in all parts for more than half the cumulative days when soil temperature at a depth of 20 inches is at or above 41 degrees F. Ustic soil moisture regime.
Mollic epipedon thickness 16 to 48 inches.
Depth to persistent seasonal high water table 24 to 42 inches.
Weighted average of clay in the particle size control section: 8 to 18 percent.
Some profiles have a non-gleyed C horizon between the A2 and Cg horizons.
Some profiles have a 2C horizon with sand, coarse sand and coarse sandy loam textures below a depth of 40 inches.
Gravel throughout the profile is mainly fine pea gravel less than 7 mm in diameter.
Oe Horizon Value: 2 or 3 moist; 3 to 5 dry
Chroma: 2 or 3
Organic carbon: 15 to 30 percent
Reaction: pH 5.2 to 6.8
A Horizons Hue: 10YR, 2.5Y, or 5Y
Value: 3 or 4 dry; 2 or 3 moist
Chroma: 1, 2, or 3
Texture: sandy loam, coarse sandy loam, loam or silt loam
Clay content: 8 to 20 percent
Rock fragments: 0 to 35 percent--0 to 10 percent cobbles, stones and boulders, 0 to 30 percent, mainly fine, gravel
Reaction: pH 6.0 to 7.6
Note: textures may be stratified
Cg Horizon Hue: 10YR, 2.5Y, or 5Y
Value: 5 or 6 dry; 3, 4 or 5 moist
Chroma: 1, 2, or 3
Texture: sandy loam, loam or silt loam with thin strata of coarse sand or loamy coarse sand commonly present
Clay content: 8 to 18 percent
Rock fragments: 0 to 20 percent--0 to 5 percent cobbles, stones and boulders, 0 to 15 percent, mainly fine, gravel
Reaction: pH 6.6 to 7.8
COMPETING SERIES: This is the Cablab series. Cablab soils have a xeric temperature regime and contain rock fragments with mixed lithology.
GEOGRAPHIC SETTING:
Landform- drainageways, swales, and footslopes adjacent to floodplains
Elevation - 5,100 to 7,170 feet
Slope - 2 to 20 percent
Parent material - alluvium from mixed sources with strata of coarse alluvium from granite or other coarse grained, igneous or metamorphic rocks
Climate - long cold winters; cool, moist springs; short, generally dry summers
Mean annual precipitation - 15 to 19 inches
Mean annual air temperature - 34 to 40 degrees F.
Frost-free period - 30 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Moosejaw, Mooseflat, and Basincreek series. Moosejaw soils are very poorly drained and occur in wetter portions of floodplains and drainageways. Mooseflat soils are very poorly drained and are sandy or sandy-skeletal below 14 to 26 inches. Mooseflat soils occur in wetter portions of floodplains, bogs, and drainageways. Basincreek soils are well drained and occur on adjacent hill or mountain slopes.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; moderate to moderately rapid permeability.
USE AND VEGETATION: Pappascreek soils are primarily used for rangeland and wildlife habitat. Native vegetation in grassland areas is mainly Nelsons needlegrass, slender wheatgrass, slender cinquefoil, shrubby cinquefoil, Baltic rush, Douglas sedge and Rocky Mountain iris along with naturalized Kentucky bluegrass. Understory vegetation, in areas with an aspen overstory, is mainly bluejoint reedgrass, sticky geranium, woods strawberry, woods rose, Geyer and Bebb willow, prickley gooseberry, and slender cinquefoil.
DISTRIBUTION AND EXTENT: Pappascreek soils are of limited extent in mountains and foothills of southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Silver Bow County, Montana, 2006.
REMARKS: Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from 3 to 27 inches (A1, A2 horizons); an organic surface from 0 to 3 inches; gleyed substrata from 27 to 72 inches (Cg horizon); stratified alluvium 18 to 72 inches (A2 ,Cg horizons); a particle-size control section from 13 to 43 inches (A1, A2, Cg horizons). Pappascreek soils have a cryic temperature regime and an ustic soil moisture regime.