LOCATION KATPA WYEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, carbonatic Calcic Pachic Haplocryolls
TYPICAL PEDON: Katpa gravelly silt loam, on a 46 percent slope with south aspect at 8480 feet elevation, in an area of subalpine fir/western meadowrue h.t., open canopy woodland. (Colors are for dry soil unless otherwise noted.)
Oi--0 to 0.5 inch; discontinuous forest litter of nondecomposed and decomposed needles and leaves; abrupt broken boundary. (0 to 5 inches thick)
A1--0.5 to 2 inches; brown (10YR 5/3) gravelly silt loam, very dark grayish brown (10YR 3/2) moist; weak coarse granular structure parting to weak fine granular; soft, very friable, nonsticky and slightly plastic; many very fine roots; many very fine irregular pores; 20 percent pebbles, trace cobbles and stones; neutral (pH 6.6); abrupt smooth boundary. (1 to 5 inches thick)
A2--2 to 7 inches; brown (10YR 4/3) gravelly silt loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure parting to weak fine granular; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and few medium roots; many very fine irregular pores; 25 percent pebbles, trace cobbles and stones; slightly alkaline (pH 7.5); abrupt wavy boundary. (0 to 10 inches thick)
A3--7 to 16 inches; brown (10YR 5/3) very gravelly silt loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and few medium roots; many very fine tubular pores; 40 percent pebbles, trace cobbles and stones; slightly alkaline (pH 7.6); clear wavy boundary. (5 to 10 inches thick)
Bk1--16 to 32 inches; brown (10YR 5/3) extremely gravelly silt loam, dark brown (10YR 3/3) moist; weak very fine granular structure; soft, very friable, nonsticky and slightly plastic; many very fine, few fine and common medium roots; many very fine irregular pores; common hard pendants of carbonates and many coats of soft powdery lime on underside of cobbles and coarse pebbles; slightly effervescent; 45 percent pebbles, 20 percent cobbles and trace stones; slightly alkaline (pH 7.8), gradual wavy boundary. (10 to 20 inches thick)
Bk2--32 to 60 inches; brown (10YR 5/3) extremely cobbly loam, brown (10YR 4/3) moist; weak very fine granular structure; soft, very friable, nonsticky and slightly plastic; common very fine and few medium roots; many very fine irregular pores; many hard pendants of carbonates and many coats of soft powdery lime on underside of rock fragments; strongly effervescent; 30 percent pebbles, 50 percent cobbles and trace stones; moderately alkaline (pH 8.0).
TYPE LOCATION: Teton County, Wyoming: 750 feet west and 100 feet north of the southeast corner of section 12, T. 43 N., R. 118 W.; Latitude - 43 degrees North, 41 minutes, 48 seconds; Longitude - 111 degrees West, 56 minutes, 31 seconds.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 36 to 42 degrees F.
Mean summer soil temperature - 41 to 46 degrees F. with an O horizon; 49 to 53 degrees F. without an O horizon.
Moisture control section - between 8 and 24 inches; dry throughout the moisture control section for 30 to 45 consecutive days during the four months following the summer solstice.
Mollic epipedon thickness - 16 to 40 inches.
Depth to carbonates - 10 to 25 inches.
Depth to calcic horizon - 16 to 40 inches.
Control section - Calcium carbonate equivalent of the less than 20mm size fraction: greater than 40 percent.
A horizons - Hue: 7.5YR or 10YR
Value: 4 or 5 dry, 3 or 4 moist
Chroma: 2 or 3 dry or moist
Texture: silt loam or loam
Clay content: 10 to 18 percent
Rock fragments: 15 to 60 percent--0 to 10 percent stones; 0 to
20 percent cobbles; 10 to 40 percent pebbles
Calcium carbonate equivalent in the less than 2mm size fraction: 0 to 5 percent
Reaction: 6.6 to 7.8
Bk1 horizon - Hue: 7.5YR or 10YR
Value: 4 or 5 dry, 3 moist
Chroma: 3 dry or moist
Texture: loam or silt loam
Clay content: 12 to 18 percent
Rock fragments: 40 to 70 percent--0 to 10 percent stones; 0 to 30
percent cobbles; 30 to 60 percent pebbles
Effervescence: slightly or strongly effervescent
Calcium carbonate equivalent of the less than 2mm size fraction: 2 to 15 percent
Reaction: 7.4 to 7.8
Bk2 horizon - Hue: 7.5YR or 10YR
Value: 5, 6 or 7 dry; 4 or 5 moist
Chroma: 3 or 4 dry or moist
Texture: loam or sandy loam
Clay content: 4 to 16 percent
Rock fragments: 60 to 90 percent--0 to 10 percent stones; 5 to
50 percent cobbles; 30 to 70 percent pebbles
Effervescence: strongly or violently effervescent
Calcium carbonate equivalent in the less than 2 mm size fraction: 15 to 40 percent
Reaction: 7.9 to 8.4
COMPETING SERIES:
Kitchell (UT) - have 18 to 35 percent clay in the particle size control section; have a mean annual soil temperature of 42 to 47 degrees F.
GEOGRAPHIC SETTING:
Landform - south facing mountain sideslopes.
Elevation - 6,700 to 9,800 feet.
Slope - 40 to 70 percent.
Parent material - local alluvium and colluvium derived from
limestone and loess.
Climate - 4 to 10 foot winter snowpack, moist summers.
Mean annual air temperature - 34 to 40 degrees F.
Mean annual precipitation - 24 to 34 inches.
Frost free period - 15 to 45 days.
DRAINAGE AND PERMEABILITY: Well drained, moderate permeability, moderate runoff.
USE AND VEGETATION: Katpa soils are used for recreation and wildlife habitat. These soils commonly support open canopy forested communities. These communities are commonly associated with the subalpine fir/western meadowrue plant association.
DISTRIBUTION AND EXTENT: Western Wyoming and southeastern Idaho. These soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Targhee National Forest, Teton County, Wyoming, 1997.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the mineral soil surface to 32 inches (the A1, A2, A3 and Bk1 horizons).
Calcic horizon - The zone from 16 to 60 inches (the Bk1 and Bk2 horizons).
Particle size control section - The zone from 10 to 40 inches (part of the A3, the Bk1 and part of the Bk2 horizons).
Carbonatic mineralogy - greater than 40 percent CaCO3 in the less than 20mm size fraction.
Moisture regime - udic.