LOCATION REDRAVEN IDEstablished Series
TAXONOMIC CLASS: Medial over loamy-skeletal, glassy over mixed, superactive Typic Haplocryands
TYPICAL PEDON: Redraven bouldery medial silt loam, forest; on a southwest facing slope of 23 percent at 5000 feet elevation. When described on September 29, 1982, the soil was moist to 17 inches and very slightly moist below. (Colors are for dry soil unless otherwise stated).
Oi--0 to 1 inch; slightly decomposed needles, leaves, and twigs. (1 to 2.5 inches thick)
Oe--1 to 2 inches; decomposed organic matter. (0.5 to 1.5 inches thick)
A--2 to 4 inches; brown (10YR 5/3) bouldery medial silt loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure parting to moderate fine granular; soft, very friable, nonsticky and slightly plastic; many very fine and fine roots; many very fine and fine tubular pores; 5 percent pebbles, 5 percent cobbles, 10 percent stones and boulders; boulders cover 0.1 percent of the surface; neutral (pH 7.0); clear irregular boundary. (1 to 3 inches thick)
Bw1--4 to 10 inches; pale brown (10YR 6/3) bouldery medial silt loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and slightly plastic; common very fine, fine, medium, and few coarse roots; common very fine and fine tubular pores; 5 percent pebbles and 5 percent cobbles, 10 percent stones and boulders; neutral (pH 7.0); clear wavy boundary. (3 to 7 inches thick)
Bw2--10 to 19 inches; light yellowish brown (10YR 6/4) bouldery medial silt loam, dark yellowish brown (10YR 4/4) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and slightly plastic; common very fine, fine, medium, and few coarse roots; common very fine and fine tubular pores; 10 percent pebbles, 5 percent cobbles, and 10 percent stones and boulders; neutral (pH 7.0); abrupt wavy boundary. (8 to 12 inches thick)
2Bw3--19 to 31 inches; light yellowish brown (10YR 6/4) very bouldery loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; common fine and medium roots; common very fine and fine interstitial and few fine tubular pores; 20 percent pebbles, 15 percent cobbles, and 25 percent stones and boulders; neutral (pH 6.8); clear wavy boundary. (10 to 17 inches thick)
2BC--31 to 46 inches; pale yellow (2.5Y 7/4) extremely bouldery sandy loam, light olive brown (2.5Y 5/4) moist; weak fine subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; few fine and medium roots matted along rock faces; common very fine tubular and interstitial pores; 30 percent pebbles, 20 percent cobbles, and 30 percent stones and boulders; moderately acid (pH 5.8); gradual wavy boundary. (7 to 18 inches thick)
2C--46 to 60 inches; pale yellow (2.5Y 7/4) extremely bouldery loamy sand, light olive brown (2.5Y 5/4) moist; massive; slightly hard, friable, nonsticky and nonplastic; few very fine roots on rock faces; many very fine and fine interstitial pores; few medium brownish yellow (10YR 6/8) iron stains; 35 percent pebbles, 20 percent cobbles, and 35 percent stones and boulders; moderately acid (pH 6.0).
TYPE LOCATION: Shoshone County, Idaho; about 11 miles southwest of Avery, about 1,950 feet south and 100 feet west of the northeast corner of section 12, T.44 N., R.3 E. Latitude - 47 degrees, 10 minutes, 21 seconds North, Longitude - 116 degrees, 01 minute, 02 seconds West.
RANGE IN CHARACTERISTICS:
Depth to bedrock - more than 60 inches
Solum thickness - 36 to 55 inches
Moisture control section - dry August to mid September (15 to 25 days); moist September through July; udic moisture regime
Average annual soil temperature - 38 to 42 degrees F
Average summer soil temperature - 44 to 46 degrees F with an O horizon
Surface stones and boulders - 0 to 3 percent
Volcanic ash mantle - 14 to 20 inches thick
Volcanic glass content in the 0.02 to 2.0 mm fraction - 20 to 65 percent
Acid-oxalate extractable Al + 1/2 Fe - 2.0 to 4.0 percent
Phosphate retention 80 to 100 percent
15-bar water retention on air dried samples - 15 to 18 percent
A horizon
Value - 4 to 6 dry, 2 to 4 moist
Chroma - 1 to 3 dry or moist
Texture - BY-SIL, ST-SIL, CB-SIL, GR-SIL, SIL (all medial)
Clay content - 3 to 9 percent
Rock fragment content - 5 to 25 percent
Bulk density - 0.65 to 0.90 grams per cubic centimeter
Reaction - moderately acid to neutral
Bw horizons
Hue - 10YR or 7.5YR
Value - 5 or 6 dry, 3 or 4 moist
Texture - BY-SIL, ST-SIL, CB-SIL, GR-SIL, SIL (all medial)
Clay content - 3 to 9 percent
Rock fragment content - 5 to 30 percent
Bulk density - 0.65 to 0.90 grams per cubic centimeter
Reaction - moderately acid to neutral
2Bw horizon
Hue - 10YR, 7.5YR, or 2.5Y
Value - 5 to 7 dry, 4 or 5 moist
Chroma - 3 or 4 dry or moist
Texture - STV-L, CBV-L, CBV-SIL, BYV-L, BYV-SL, GRV-FSL, CBV-SL, GRV-SL
Clay content - 3 to 9 percent
Rock fragment content - 35 to 60 percent
Reaction - moderately acid to neutral
2BC horizon
Hue - 10YR or 2.5Y
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 3 or 4 dry or moist
Texture - BYX-SL, STX-SL, GRV-SL, CBV-SL, STV-SL
Clay content - 3 to 9 percent
Rock fragment content - 40 to 80 percent
Reaction - moderately acid to slightly acid
2C horizon
Hue - 10YR or 2.5Y
Value - 6 to 8 dry, 4 to 6 moist
Chroma - 2 or 4 dry or moist
Texture - STX-LS, STX-SL, BYX-LS, BYX-SL, CBX-SL, GRV-SL, CBV-SL, STV-SL, GRV-LS, STV-FSL
Clay content - 0 to 5 percent
Rock fragment content - 45 to 90 percent
Reaction - moderately acid to slightly acid
COMPETING SERIES: These are the Baldeagle and Katka series. Baldeagle soils do not have a 2Bw horizon. Katka soils have dark colored AB horions and are dry for 30 to 45 days in the moisture control section.
GEOGRAPHIC SETTING: Redraven soils are in glacial troughs, moraines, and cirque basins, and on glaciated mountain slopes and ridgetops. Slopes range from 0 to 80 percent. These soils formed in glacial till derived from granite, gneiss, schist, or quartzite rocks with a thick mantle of volcanic ash. Elevations range from 4,200 to 6,350 feet. The average annual air temperature ranges from 38 to 42 degrees F, average annual precipitation is 40 to 60 inches, and frost-free season is from 30 to 60 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bouldercreek, Vaywood and the competing Vay soils. Bouldercreek soils are on mountainsides at lower elevations and are frigid. Vay and Vaywood soils are on mountain slopes and ridgetops.
DRAINAGE AND PERMEABILITY: well drained; medium to rapid runoff; moderate permeability in the solum and moderately rapid to rapid in the substratum.
USE AND VEGETATION: These soils are used for timber production, wildlife habitat, recreation, and watershed. Potential natural vegetation is mainly subalpine fir, mountain hemlock, and Engelmann spruce, with an understory of big blueberry, common beargrass, myrtle pachystima, rustyleaf menziesia, elk sedge, queencup beadlily, Utah honeysuckle, and Sitka mountainash.
DISTRIBUTION AND EXTENT: Northern Idaho. This soil is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: St. Joe soil survey area, Shoshone County, Idaho, 1993.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the mineral soil surface to 7 inches (A and part of Bw1 horizons)
Cambic horizon - the zone from 10 to 46 inches (Bw2, 2Bw3, and 2BC horizons)
Volcanic ash mantle - the zone from the mineral soil surface to 19 inches (A, Bw1, and Bw2 horizons)
Particle-size control section - the zone from the mineral soil surface to 40 inches (A, Bw1, Bw2, 2Bw3, and part of 2BC horizon)