LOCATION DISALTO                 ID

Established Series
Rev. BDG-JAL-EMM
07/2013

DISALTO SERIES

The Disalto series consists of very deep, well drained soils on mountain side slopes and ridges. They formed in loess over material from quartzite and phyllite of the Wallace Formation of the Belt supergroup that is blanketed by a thick mantle of volcanic ash. Saturated hydraulic conductivity is moderately high. Slope ranges from 5 to 60 percent. The average annual temperature is about 43 degrees F. and the average annual precipitation is about 39 inches.

TAXONOMIC CLASS: Ashy over loamy, amorphic over mixed, superactive, frigid Alfic Udivitrands

TYPICAL PEDON: Disalto ashy silt loam - forested - on a southwest-facing slope of 30 percent at 3,350 feet elevation. (Colors are for dry soil unless otherwise stated). When described on July 16 2002, the soil was dry throughout.

Oe--0 to 1 inch; partially decomposed needles, twigs, leaves and moss.

A--1 to 2 inches; dark grayish brown (10YR 4/2) ashy silt loam, dark brown (10YR 3/3) moist; moderate very fine and fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots; many very fine and fine tubular pores; moderately acid (pH 6.0); abrupt smooth boundary. (1 to 5 inches thick)

Bw1--2 to 8 inches; yellowish brown (10YR 5/4) ashy silt loam, dark brown (7.5YR 3/4) moist; weak fine and medium subangular blocky structure parting to weak very fine and fine granular; soft, very friable, nonsticky and nonplastic; many very fine and fine, common medium and few coarse roots; many very fine and fine tubular pores; neutral (pH 6.6); clear wavy boundary.

Bw2--8 to 17 inches; light yellowish brown (10YR 6/4) ashy silt loam, dark yellowish brown (10YR 3/6) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and fine and common medium and coarse roots; many very fine and fine and few medium tubular pores; slightly acid (pH 6.4); abrupt wavy boundary. (Combined thickness of Bw horizons is 11 to 20 inches)

2Bt1--17 to 23 inches; light yellowish brown (10YR 6/4) silt loam, dark yellowish brown (10YR 4/4) moist; moderate fine and medium subangular blocky structure; hard, friable, slightly sticky and moderately plastic; common very fine and fine roots between peds, few medium roots; many very fine, few fine and medium tubular pores; many distinct clay films on vertical faces of peds and on surfaces along pores; common distinct skeletans on vertical faces of peds; 10 percent fine mica flakes; 2 percent paragravel; moderately acid (pH 6.0); clear wavy boundary.

2Bt2--23 to 30 inches; very pale brown (10YR 7/3) silt loam, dark yellowish brown (10YR 4/6) moist; moderate fine and medium subangular blocky structure; hard, friable, slightly sticky and moderately plastic; common very fine and fine roots between peds; many very fine and few fine tubular pores; many distinct clay films on vertical faces of peds and on surfaces along pores; common distinct skeletans on vertical faces of peds; 10 percent fine mica flakes; 5 percent paragravel; moderately acid (pH 5.6); abrupt wavy boundary. (Combined thickness of 2Bt horizons is 13 to 23 inches)

3BCt--30 to 36 inches; very pale brown (10YR 7/3) very fine sandy loam, dark yellowish brown (10YR 4/6) moist; weak fine and medium subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; common very fine and fine roots between peds, few medium and coarse; common very fine tubular pores; common faint clay films on surfaces along pores; 15 percent fine mica flakes; 10 percent paragravel; moderately acid (pH 5.6); clear wavy boundary. (6 to 10 inches thick)

3C1--36 to 45 inches; very pale brown (10YR 7/4) paragravelly very fine sandy loam, yellowish brown (10YR 5/6) moist; massive; slightly hard, friable, nonsticky and nonplastic; common very fine and fine and few medium and coarse roots; few very fine tubular pores; 15 percent fine mica flakes; 30 percent paragravel; moderately acid (pH 5.6); clear wavy boundary.

3C2--45 to 51 inches; 95 percent very pale brown (10YR 7/4) and 5 percent brownish yellow (10YR 6/6) paragravelly very fine sandy loam, 95 percent yellowish brown (10YR 5/6) and 5 percent yellowish red (5YR 4/6) moist; massive; slightly hard, friable, nonsticky and nonplastic; common very fine roots in cracks, few fine and medium throughout; few very fine tubular pores; 15 percent fine mica flakes; 25 percent paragravel; strongly acid (pH 5.4); clear wavy boundary.

3C3--51 to 60 inches; 60 percent very pale brown (10YR 7/4), 30% very pale brown (10YR 8/3) and 10 percent brownish yellow (10YR 6/6) very paragravelly very fine sandy loam, 90 percent yellowish brown (10YR 5/6) and 10 percent yellowish red (5YR 4/6) moist; massive; slightly hard, friable, nonsticky and nonplastic; common very fine and fine roots in cracks; few very fine tubular pores; 15 percent fine mica flakes; 60 percent paragravel; strongly acid (pH 5.3).

TYPE LOCATION: Latah County, Idaho; about 3 miles north and 17 miles east of Potlatch, Idaho; about 1,350 feet south and 950 feet east of the northwest corner of Sec. 24, T42N, R2W; Latitude 46 degrees, 58 minutes, 34 seconds North and Longitude 116 degrees 32 minutes, 30 seconds West; UTM Zone 11 Northing 5202542 meters and Easting 0534945 meters; USGS Sand Mountain Quadrangle.

RANGE IN CHARACTERISTICS:

Solum thickness - 37 to greater than 60 inches
Soil moisture control section - usually moist year around and not dry for 45 consecutive days during June to October. Udic moisture regime.
Average annual soil temperature - 39 to 45 degrees F.

Volcanic ash cap thickness - 15 to 26 inches inches
Volcanic glass content in the 0.02 to 2.0 mm fraction - 15 to 60 percent
Acid-oxalate extractable Al plus 1/2 Fe - 1.3 to 2.7 percent
Phosphate retention - 75 to 90 percent
15-bar water retention on air dried samples - 9 to 13 percent (weighted average is less than 12 percent)
Moist bulk density - 0.50 to 0.95 g/cc

A horizon
Hue - 7.5YR or 10YR moist
Value - 4 or 5 dry, 3 or 4 moist
Chroma - 2 to 4 dry and 3 or 4 moist
Clay content - 8 to 10 percent
Reaction - 5.8 to 6.7

Bw horizons
Hue - 7.5YR or 10YR dry or moist
Value - 5 to 7 dry, 3 to 5 moist
Chroma - 4 to 6 dry or moist
Clay content - 4 to 10 percent
Rock fragment - 0 to 1 percent gravel
Reaction - 5.6 to 6.8

2E horizons (present in some pedons)
Hue - 10YR dry and 7.5YR moist
Value - 7 dry and 4 moist
Chroma - 3 dry and 4 moist
Texture - silt loam
Clay content - 16 to 18 percent
Reaction - 5.4 to 6.3

2Bt horizons
Hue - 7.5YR or 10YR dry or moist
Value - 5 to 7 dry and 3 to 5 moist
Chroma - 3 to 6 dry or moist
Texture - loam or silt loam
Clay content - 8 to 21 percent
Rock fragments - 0 to 15 percent gravel
Pararock fragments - 2 to 5 percent paragravel
Mica content - 0 to 10 percent
Reaction - 5.4 to 6.3

3BCt and 3Bt horizons (3Bt horizon present in some pedons)
Hue - 7.5YR or 10YR dry or moist
Value - 5 to 7 dry and 4 or 5 moist
Chroma - 3 to 6 dry or moist
Texture - silt loam, loam or very fine sandy loam
Clay content - 4 to 19 percent
Rock fragments - 0 to 25 percent gravel, 0 to 2 percent cobbles, 0 to 25 percent total rock fragment content
Pararock fragments - 0 to 15 percent paragravel
Mica content - 0 to 15 percent
Reaction - 5.1 to 6.2

3C horizons
Hue - 5YR to 10YR moist
Value - 6 to 8 dry and 4 or 5 moist
Chroma - 3 to 6 dry or moist
Texture - fine sandy loam or very fine sandy loam
Clay content - 3 to 12 percent
Rock fragments - 0 to 25 percent gravel, 0 to 2 percent cobbles, 0 to 25 percent total rock fragment content
Pararock fragments - 0 to 60 percent paragravel
Mica content - 0 to 15 percent
Reaction - 5.1 to 6.2

COMPETING SERIES:

Brodeer soils: do not have two lithologic discontinuities within the profile

Chesley soils: are deep to a paralithic contact

Cranberry soils: do not have subsoil horizons with very fine sandy loam or fine sandy loam textures and contain basalt fragments

Dworshak soils: do not have subsoil horizons with very fine sandy loam or fine sandy loam textures

Helmer soils: are shallow to a fragipan

Scand soils: have more than 30 percent mica in the 3Bt, 3BC, and 3C horizons

GEOGRAPHIC SETTING: The Disalto soils are on mountain sides and ridge summits. Slopes range from 5 to 60 percent. These soils formed in loess over quartzite or phyllite with a thick mantle of volcanic ash at elevations of 2,740 to 5,050 feet (835 to 1540 meters). The average annual temperature ranges from 40 to 45 degrees F, with an average annual precipitation of 31 to 55 inches (787 to 1397 mm). The frost free season is 85 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are Secunda, Flewsie and Bouldercreek soils. Secunda and Flewsie soils do not have a horizon formed in loess and are on steep mountain sides and narrow ridges. Bouldercreek soils have more than 35 percent rock fragments below an ash cap and are on steep mountain sides.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; moderately high saturated hydraulic conductivity.

USE AND VEGETATION: These soils are used for timber production, livestock grazing, wildlife habitat, watershed, and recreation. Potential natural vegetation is western red cedar, grand fir, western hemlock, western larch, western white pine, Douglas-fir, and ponderosa pine, with an understory of wild ginger, queencup beadlily, coolwort foamflower, pioneer violet, princes pine, and fools huckleberry.

DISTRIBUTION AND EXTENT: North-central Idaho. The series is not extensive. MLRA 43A.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Latah County, Idaho, 2013.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - The zone from the mineral soil surface to 2 inches (Oe and A horizons).

Cambic horizon - The zone from 2 to 17 inches (Bw1 and Bw2 horizons).

Argillic horizon - The zone from 17 to 30 inches (2Bt1 and 2Bt2 horizons).

Andic soil properties - The zone from 1 to 17 inches (A, Bw1 and Bw2 horizons).

Particle-size control section - The zone from 1 to 41 inches (A, Bw1, Bw2, 2Bt1, 2Bt2, 3BC and part of the 3C1 horizons).

ADDITIONAL DATA: Laboratory data exists for this pedon:
Laboratory pedon number 02N1044 and soil survey pedon ID number S02ID-057-002

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National Cooperative Soil Survey
U.S.A.