LOCATION BANDMILL IDEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Andic Hapludalfs
TYPICAL PEDON: Bandmill ashy silt loam, forested on a 17 percent slope at 2,960 feet elevation. Aspect is northeast. When described on October 17, 1994, the soil was moist throughout. (colors are for dry soil unless otherwise noted)
Oi--0 to 2 inches; partially decomposed needles, leaves and moss.
A--2 to 3 inches; strong brown (7.5YR 4/6) ashy silt loam, dark brown (7.5YR 3/3) moist; weak very fine and fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine and common medium roots throughout; many very fine and fine irregular pores; 2 percent fine rounded iron-manganese concretions; neutral (pH 6.6); abrupt wavy boundary. (1 to 8 inches thick)
Bw--3 to 10 inches; brown (7.5YR 5/4) ashy silt loam, brown (7.5YR 4/4) moist; moderate fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; few very fine and fine and common medium and coarse roots throughout; many very fine and fine irregular and common fine tubular pores; 2 percent fine and medium rounded iron-manganese concretions; slightly acid (pH 6.2); abrupt wavy boundary. (5 to 11 inches thick)
2Bt1--10 to 17 inches; light yellowish brown (10YR 6/4) silt loam, dark yellowish brown (10YR 4/4) moist; moderate medium and coarse subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; few very fine and fine and common medium roots between peds; many very fine and fine irregular and common fine tubular pores; many distinct brown (7.5YR 4/4) moist clay films on faces of peds and in pores; common distinct very pale brown (10YR 7/3) skeletans in pores; 2 percent medium rounded iron-manganese concretions; 1 percent fine mica flakes; slightly acid (pH 6.2); clear wavy boundary.
2Bt2--17 to 21 inches; pale brown (10YR 6/3) silt loam, dark yellowish brown (10YR 4/4) moist; moderate medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, fine and medium roots between peds; many very fine and fine irregular and common fine tubular pores; many distinct brown (7.5YR 4/4) moist clay films on faces of peds and in pores; many distinct very pale brown (10YR 7/3) skeletans on faces of peds and in pores; 2 percent fine rounded iron-manganese concreations; 1 percent fine mica flakes; moderately acid (pH 6.0); abrupt wavy boundary. (2Bt horizons 0 to 21 inches thick)
2E/Bt--21 to 27 inches; 70 percent E material: pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist and 30 percent B material: light brown (7.5YR 6/4) silt loam, dark yellowish brown (10YR 4/4) moist; moderate medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots between peds; common very fine and fine irregular and few very fine tubular pores; many distinct brown (7.5YR 4/4) moist clay films on faces of peds and in pores; common distinct very pale brown (10YR 7/3) skeletans in pores; common fine and medium rounded iron-manganese concretions; 3 percent subangular basalt gravel; moderately acid (pH 5.6); abrupt wavy boundary. (0 to 12 inches thick)
3Btb1--27 to 34 inches; light brown (7.5YR 6/4) silty clay loam, brown (7.5YR 5/4) moist; weak coarse prismatic structure parting to strong fine and medium subangular blocky; hard, firm, moderately sticky and moderately plastic; few very fine and fine roots between peds; common very fine and fine irregular and few very fine tubular pores; many prominent skeletans on faces of peds; 1 percent medium rounded iron-manganese concretions; 3 percent subangular basalt gravel; very strongly acid (pH 4.6); clear wavy boundary.
3Btb2--34 to 65 inches; brown (7.5YR 5/4) silty clay loam, strong brown (7.5YR 4/6) moist; weak coarse prismatic structure parting to strong fine and medium subangular blocky; very hard, very firm, moderately sticky and moderately plastic; few very fine and fine roots between peds; common very fine and fine irregular and few very fine tubular pores; many prominent skeletans on faces of peds; 10 percent subangular basalt gravel; strongly acid (pH 5.4).
TYPE LOCATION: Clearwater County, Idaho; about 9 miles east of Orofino, Idaho; about 1500 feet south and 1450 feet west of northeast corner of section 10, T 36N., R 3E.; Latitude - 46 degrees, 28 minutes, 52 seconds North; Longitude - 116 degrees, 3 minutes, 54 seconds West; USGS Rudo quadrangle.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 43 to 46 degrees F. Frigid temperature regime.
Soil moisture control section - usually moist throughout, not dry for 45 consecutive days following the summer solstice. Udic moisture regime.
Thickness of volcanic ash mantle - 8 to 13 inches
Volcanic glass content - 5 to 33 percent
Acid - oxalate Al plus 1/2 Fe - 1.2 to 2.3 percent
Phosphate retention - 60 to 95 percent
15 bar water retention - 8.0 to 16.5 percent
A horizon
Hue - 10YR or 7.5YR
Value - 4 to 6 dry
Chroma - 2 to 6 dry; 2 to 4 moist
Clay content - 8 to 12 percent
Rock fragments - 0 to 3 percent gravel; 0 to 3 percent cobbles; 0 to 3 percent total fragment content
Reaction - strongly acid to neutral
Bw horizon
Hue - 10YR or 7.5YR
Value - 5 or 6 dry; 3 or 4 moist
Clay content - 8 to 12 percent
Rock fragments - 0 to 3 percent gravel; 0 to 3 percent cobbles; 0 to 3 percent total fragment content
Reaction - strongly acid to slightly acid
2Bt horizons
Hue - 10YR, 7.5YR or 5YR
Value - 5 or 6 dry; 3 to 5 moist
Texture - SIL, SICL, SIC
Clay content - 16 to 35 percent
Rock fragments - 0 to 3 percent gravel; 0 to 3 percent cobbles; 0 to 3 percent total fragment content
Reaction - extremely acid to slightly acid
2E/B and 2B/E horizons
E part:
Value - 6 or 7 dry; 4 to 6 moist
Chroma - 3 or 4 dry; 2 to 4 moist
Clay content - 15 to 24 percent
B part:
Hue - 10YR or 7.5YR
Value 5 or 6 dry; 3 to 5 moist
Chroma - 3 to 4 moist
Texture - SIL or SICL
Clay content - 18 to 34 percent
Rock fragments - 0 to 3 percent gravel; 0 to 3 percent cobbles; 0 to 3 percent total fragment content
Reaction - moderately acid or strongly acid
2E horizon present in some pedons.
3Btb horizons
Hue - 10YR or 7.5YR
Value - 4 to 7 dry; 3 to 5 moist
Chroma - 4 to 6 dry; 3 to 6 moist
Clay content - 25 to 40 percent
Texture - SIL, SICL, CL, or SIC
Rock fragments - 0 to 10 percent gravel; 0 to 3 percent cobble; 0 to 10 percent total fragment content
Reaction - very strongly acid to slightly acid
COMPETING SERIES: These are the Brequito, Riswold, and Scaler series. Brequito soils have 3BC and 3C horizons with textures of loam and sandy loam. Riswold soils have more than 25 percent rock fragments in the 3Bt horizons. Scaler soils are paramicaceous in the lower subsoil.
GEOGRAPHIC SETTING: Bandmill soils are on hills on plateaus and structural benches in canyons at elevations of 1,600 to 3,400 feet. Slopes are 5 to 40 percent. The soils formed in loess over basalt residuum with a thin mantle of volcanic ash. The average annual temperature is 38 to 44 degrees F. and the average annual precipitation is 30 to 45 inches. The frost free season is 50 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aldermand, Elkridge, Grangemont and Riswold series. Aldermand soils are on canyon and mountain slopes, are coarse-loamy and have vitrandic properties. Elkridge soils are on hills and canyon slopes and are loamy-skeletal. Grangemont soils are on hills and have fragic characteristics. Riswold soils are on low hills and structural benches and have more than 25 percent rock fragments in the lower argillic.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for timber production, wildlife habitat, recreation and watershed. Potential natural vegetation is western redcedar, grandfir, western larch, Douglas-fir and ponderosa pine with an understory of queencup beadlilly, goldthread, bunchberry dogwood, starry false Solomons seal, sweetscented bedstraw, American trailplant, western thimbleberry, Rocky Mountain maple and common snowberry.
DISTRIBUTION AND EXTENT: North central Idaho. Bandmill soils are not 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 from 2 to 10 inches. (A and Bw horizons)
Cambic horizon - The zone from 3 to 10 inches. (Bw horizon)
Argillic horizon - The zone from 10 to 21 inches. (2Bt1 and 2Bt2 horizons)
Buried argillic horizon - The zone from 27 to 62 inches. (3Btb1 and 3Btb2 horizons)
Volcanic ash cap - The zone from 2 to 10 inches. (A and Bw horizons)
Particle size control section - The zone from 10 to 21 inches. (2Bt1 and 2Bt2 horizons)
The ranges of values listed in the Range In Characteristics for volcanic glass, acid-oxalate Al+1/2Fe, phosphate retention and 15 bar water retention are estimates only.