LOCATION RAPID                   ID+WY

Established Series
Rev. CBR/TDT
04/2011

RAPID SERIES

The Rapid series consists of very deep, well drained soils formed in colluvium weathered from rhyolite. Rapid soils are on side slopes of canyons and have slopes of 20 to 85 percent. The mean annual precipitation is about 430 mm and the mean annual air temperature is about 2.5 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Pachic Palecryolls

TYPICAL PEDON: Rapid silt loam on a side slope of a canyon with 49 percent slope at an elevation of 1,783 meters. (Colors are for dry soil unless otherwise noted.) The surface is covered by 10 percent cobbles and 10 percent stones.

Oi--0 to 3 cm; slightly decomposed fir needles; abrupt smooth boundary.

Oe--3 to 8 cm; black (10YR 2/1) moderately decomposed plant material, black (10YR 2/1) moist; about 20 percent fiber; common very fine, fine, medium and coarse roots; neutral (pH 7.1); abrupt smooth boundary. (Combined thickness of the O horizons is 6 to 8 cm)

A1--8 to 25 cm; grayish brown (10YR 5/2) silt loam, very dark brown (10YR 2/2) moist; weak medium subangular blocky structure; moderately hard, very friable, slightly sticky and nonplastic; common very fine, fine, medium and coarse roots; common very fine and fine tubular pores; 10 percent gravel; neutral (pH 7.3); clear wavy boundary.

A2--25 to 45 cm; grayish brown (10YR 5/2) gravelly silt loam, dark brown (7.5YR 3/2) moist; weak medium subangular blocky structure parting to weak fine subangular blocky; moderately hard, very friable, slightly sticky and slightly plastic; common very fine, fine, medium, coarse and very coarse roots; common very fine tubular pores; 15 percent gravel; neutral (pH 6.8); clear wavy boundary. (Combined thickness of the A horizons is 40 to 70 cm)

AB--45 to 65 cm; brown (10YR 5/3) very cobbly silt loam, dark brown (7.5YR 3/3) moist; moderate medium subangular blocky structure; moderately hard, very friable, slightly sticky and slightly plastic; common medium and coarse, and few fine and very fine roots; common very fine irregular, fine tubular and dendritic tubular pores; 20 percent gravel and 20 percent cobbles; neutral (pH 6.6); clear wavy boundary. (0 to 20 cm thick)

Bt1--65 to 90 cm; pale brown (10YR 6/3) very stony loam, brown (10YR 4/3) moist; moderate coarse subangular blocky structure parting to moderate medium subangular blocky; hard, friable, moderately sticky and moderately plastic; common medium roots and few very fine and fine roots; common very fine tubular and irregular pores; few (5 percent) skeletans on all faces of peds and very few (2 percent) faint clay films; 20 percent gravel, 20 percent cobbles, and 15 percent stones; moderately acid (pH 5.7); clear wavy boundary. (20 to 25 cm thick)

Bt2--90 to 152 cm; brown (7.5YR 5/3) extremely stony clay loam, brown (7.5YR 4/3) moist; moderate medium subangular blocky structure; hard, friable, moderately sticky and very plastic; few medium roots; common very fine tubular, irregular, and dendritic tubular pores; few (15 percent) distinct clay films; 15 percent gravel, 25 percent cobbles, and 40 percent stones; neutral (pH 6.8).

TYPE LOCATION: Teton County, Idaho; about 8.9 kilometers northwest of Felt; 591 meters east and 645 meter north of the southwest corner of section 21, T. 7 N., R. 44 E.; Drummond USGS topographic quadrangle; lat. 43 degrees, 55 minutes, and 2.5 seconds N. and long. 111 degrees, 16 minutes, 18.2 seconds W., NAD83.

RANGE IN CHARACTERISTICS:
Surface fragments: 3 to 15 percent stones
Mollic epipedon thickness: 50 to 90 cm
Depth to argillic horizon: 60 to 80 cm
Particle size control section rock fragments: 60 to 85 percent
Particle size control section total clay: 24 to 32 percent
Reaction: moderately acid to neutral
Soil moisture regime: udic
Mean annual soil temperature: 3.3 to 6.0 degrees C. (cryic soil temperature regime)
Mean summer soil temperature: 5.0 to 8.0 degrees C.

A horizons
Hue: 7.5YR or 10YR moist and dry
Value: 2 or 3 moist, 4 or 5 dry
Chroma: 1 or 2 moist, 2 or 3 dry
Rock fragments: 10 to 50 percent total; 10 to 30 percent gravel, 0 to 15 percent cobbles, 0 to 15 percent stones and 0 to 40 percent flagstones

Bt horizon
Hue: 7.5YR or 10YR moist and dry
Value: 3 or 4 moist, 5 or 6 dry
Chroma: 3 or 4 moist
Fine-earth texture: L or CL with 50 to 85 percent total fragments; 15 to 25 percent gravel, 15 to 25 percent cobbles, 15 to 40 percent stones and 0 to 40 percent flagstones

COMPETING SERIES: These are the Charcol, Northwater, Flygare and Parvis soils series. Charcol soils lack an O horizon. Northwater are deep. Flygare soils average less than 60 percent rock fragments in the particle size control section. Parvis soils do not have an O horizon.

GEOGRAPHIC SETTING:
Landscape: plateaus and mountains
Landform: side slope of canyons
Elevation: 1,566 to 2,227 meters
Slope: 20 to 85 percent
Parent material: colluvium weathered from rhyolite
Mean annual air temperature: 2.2 to 4.4 degrees C.
Mean annual precipitation: 406 to 813 mm
Frost free period: 30 to 55 days

GEOGRAPHICALLY ASSOCIATED SOILS: This is the Bailey soil. Bailey soils are on linear to slightly convex positions, have a calcic horizon and a frigid soil temperature regime.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: well
Runoff: high
Saturated hydraulic conductivity: moderately low

USE AND VEGETATION:
Major uses: rangeland and wildlife habitat
Dominant native vegetation: Douglas-fir, common snowberry, white spirea, Saskatoon serviceberry, Woods' rose, sticky geranium and western wheatgrass

DISTRIBUTION AND EXTENT:
Distribution: Southeastern Idaho and Western Wyoming, MLRA 13
Extent: the series is not extensive

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Teton County, Idaho, 2011; Teton Area, Idaho and Wyoming Soil Survey

REMARKS:
Diagnostic horizons and soil characteristics recognized in this pedon are:
Mollic epipedon: from a depth of 8 to 65 cm
Argillic horizon: from a depth of 65 to 152 cm
Particle size control section: from a depth of 65 to 115 cm
Soil temperature regime: cryic
Soil moisture regime: udic

ADDITIONAL DATA:
Typical pedon was not sampled.

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National Cooperative Soil Survey
U.S.A.