LOCATION DULLAXE IDEstablished Series
TAXONOMIC CLASS: Ashy over loamy, amorphic over isotic, frigid Typic Udivitrands
TYPICAL PEDON: Dullaxe ashy loam, forested, on a 55 percent slope at 3,880 feet elevation. Aspect is west. (Colors are for dry soil unless otherwise indicated)
Oi--0 to 2 inches; slightly decomposed needles, twigs, leaves and moss.
A--2 to 7 inches; brown (10YR 5/3) ashy loam, dark brown (10YR 3/3) moist; weak very fine and fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine, fine, medium and coarse roots throughout; many very fine and fine irregular and common fine and medium tubular pores; 5 percent fine mica flakes; 3 percent subangular gravel; moderately acid (pH 5.6); clear wavy boundary. (2 to 5 inches thick)
Bw1--7 to 19 inches; yellowish brown (10YR 5/4) ashy loam, dark yellowish brown (10YR 3/4) moist; weak fine and medium subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and nonplastic; many very fine and fine and common medium and coarse roots throughout; many very fine and fine irregular and common fine and medium tubular pores; 5 percent fine mica flakes; 3 percent subangular gravel; moderately acid (pH 6.0); abrupt wavy boundary. (8 to 14 inches thick)
2Bw2--19 to 27 inches; light yellowish brown (10YR 6/4) loam, dark yellowish brown (10YR 4/4) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and common fine and medium roots throughout; many very fine and fine irregular and few fine and medium tubular pores; 15 percent fine mica flakes; 2 percent subangular gravel and 1 percent subangular cobbles; moderately acid (pH 6.0); clear wavy boundary.
2Bw3--27 to 38 inches; light yellowish brown (10YR 6/4) sandy loam, yellowish brown (10YR 5/4) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine and few medium roots throughout; many very fine and fine irregular and few fine tubular pores; 10 percent fine mica flakes; 2 percent subangular gravel; moderately acid (pH 5.8); clear wavy boundary. (Combined thickness of the 2Bw horizons is 16 to 34 inches)
2BC--38 to 46 inches; 85 percent light yellowish brown (10YR 6/4) and 15 percent white (10YR 8/1) sandy loam, 85 percent yellowish brown (10YR 5/6) and 15 percent very pale brown (10YR 8/3) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; common very fine and few fine roots throughout; common very fine and fine irregular and few very fine and fine tubular pores; 5 percent fine mica flakes; moderately acid (pH 5.8); clear wavy boundary. (0 to 26 inches thick)
2C1--46 to 57 inches; 50 percent light yellowish brown (10YR 6/4) and 50 percent white (10YR 8/1) sandy loam, 50 percent yellowish brown (10YR 5/6) and 50 percent very pale brown (10YR 8/3) moist; massive; slightly hard, friable, nonsticky and nonplastic; common very fine and fine roots throughout; common very fine irregular and few very fine and fine tubular pores; 5 percent fine mica flakes; strongly acid (pH 5.5); abrupt wavy boundary. (9 to 13 inches thick)
2C2--57 to 66 inches; 50 percent very pale brown (10YR 7/3) and 50 percent white (10YR 8/1) loamy sand, 50 percent pale brown (10YR 6/3) and 50 percent very pale brown (10YR 8/3) moist; massive; slightly hard, friable, nonsticky and nonplastic; few very fine and fine roots throughout; common very fine irregular pores; 5 percent fine mica flakes; strongly acid (pH 5.4); abrupt wavy boundary.
2Cr--66 inches; soft weathered bedrock of granitic origin.
TYPE LOCATION: Clearwater County, Idaho; about 5 miles north and 5 miles east of Headquarters, Idaho; about 100 feet north and 2,300 feet east of the southwest corner of Sec. 28, T39N, R6E; Latitude - 46 degrees, 41 minutes, 17 seconds North; Longitude - 115 degrees, 42 minutes, 47 seconds West; USGS Browns Rock Quadrangle.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 39 to 45 degrees F. Frigid temperature regime.
Soil moisture control section - not dry for 45 consecutive days from June to October. Udic moisture regime.
Thickness of volcanic ash cap - 14 to 25 inches
Volcanic glass content - 15 to 50 percent
Acid-oxalate extractable Al+1/2 Fe - 1.3 to 2.7 percent
Phosphate retention - 55 to 95 percent
15 bar water content - 8 to 12 percent
A horizon
Hue - 7.5YR or 10YR moist
Value - 2 or 3 moist
Chroma - 2 to 4 moist
Texture - ASHY-L, ASHY-SIL
Clay content - 8 to 12 percent
Rock fragments - 0 to 3 percent gravel
Bulk density - 0.65 to 0.90 g/cc
Reaction - moderately acid to neutral
Bw1 horizon
Hue - 7.5YR or 10YR moist
Value - 2 or 3 moist
Chroma - 3 or 4 moist
Texture - ASHY-L, ASHY-SIL
Clay content - 8 to 12 percent
Rock fragments - 0 to 5 percent gravel
Bulk density - 0.65 to 1.00 g/cc
Reaction - moderately acid to neutral
2Bw horizons
Hue - 10YR or 2.5Y dry, 7.5YR or 10YR moist
Value - 6 or 7 dry, 3 to 6 moist
Chroma - 3 or 4 dry, 3 to 6 moist
Texture - L, SL, COSL, CB-SL, GR-L, GR-SL, GRV-L
Clay content - 5 to 18 percent
Rock fragments - 0 to 35 percent gravel, 0 to 15 percent cobbles; total rock fragment content is 0 to 35 percent
Reaction - very strongly acid to slightly acid
2BC horizon
Hue - 10YR or 2.5Y dry, 7.5YR to 2.5Y moist
Value - 6 to 8 dry, 4 to 8 moist
Chroma - 1 to 6 dry, 2 to 6 moist
Texture - SL, GR-SL, LS, LCOS
Clay content - 5 to 17 percent
Rock fragments - 0 to 15 percent gravel, 0 to 10 percent cobbles; total rock fragment content is 0 to 25 percent
Reaction - very strongly acid to moderately acid
2C horizons
Hue - 10YR or 2.5Y dry, 7.5YR to 2.5Y moist
Value - 6 to 8 dry, 3 to 8 moist
Chroma - 1 to 4 dry, 2 to 6 moist
Texture - SL, LS, COS, GR-SL, LCOS, GR-LS, GRV-COSL, GRV-LCOS
Clay content - 2 to 12 percent
Rock fragments - 0 to 40 percent gravel, 0 to 10 percent cobbles; total rock fragment content is 0 to 50 percent
Reaction - very strongly acid to moderately acid
COMPETING SERIES: This is the Flewsie series. Flewsie soils have less than 20 percent medium sand or coarser in the less than 2mm fraction.
GEOGRAPHIC SETTING: Dullaxe soils are on mountain slopes and ridges at elevations of 2,000 to 5,000 feet. They have slopes of 10 to 75 percent. These soils formed in material weathered from granitic and metamorphic rocks with a thick mantle of volcanic ash. The average annual air temperature is 38 to 44 degrees F. The average annual precipitation is 35 to 60 inches. The frost free season is 50 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brodeer (T), Grandad (T), Judgetown (T), Mushel (T), and Narnett (T) series. Brodeer soils are on moutain slopes and hills and have an argillic horizon. Grandad(T) soils are on mountain slopes and ridgetops and have an argillic horizon and a surface of more than 14 inches of volcanic ash. Judgetown soils are on mountain slopes and hills and are deep to a paralithic contact. Mushel soils are on mountain slopes and ridges and have a surface of 7 to 14 inches of volcanic ash. Narnett soils are on alluvial terraces and have a cryic soil temperature regime and a surface of 7 to 14 inches of volcanic ash.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; permeability is moderate in the upper part and moderately rapid or rapid in the lower part.
USE AND VEGETATION: These soils are used for timber production, wildlife habitat, watershed and recreation. Potential natural vegetation is western redcedar, grand fir, western larch and Douglas fir with an understory of wild ginger, queencup beadlily, goldthread, common beargrass and starry false Solomons seal.
DISTRIBUTION AND EXTENT: North-Central Idaho. These soils are moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Clearwater County, Idaho, 2003.
REMARKS: Diagnostic horizons and other features recognized in this pedon are:
Ochric epipedon - The zone 2 to 9 inches. (A and part of the Bw1 horizon)
Cambic horizon - The zone from 7 to 38 inches. (Bw1, 2Bw2 and 2Bw3 horizons)
Volcanic ash cap - The zone from 2 to 19 inches. (A and Bw1 horizons)
Particle size control section - The zone from 2 to 42 inches. (A, Bw1, 2Bw2, 2Bw3 and a part of the 2BC horizons)
The values listed in the Range In Characteristics for Bulk density, Volcanic glass, Acid-oxalate extractable Al+1/2Fe, Phosphate retention and 15-bar water retention are estimates only.