LOCATION ODONNELL                ID

Established Series
Rev. SHB-BDG-RJS
01/2016

ODONNELL SERIES

The Odonnell series consists of very deep, moderately well drained soils on hillslopes, benches and relict stream terraces. They formed in mixed materials consisting of loess, colluvium and alluvium derived from anorthosite, schist, and gneiss bedrock with a thick mantle of volcanic ash. Some pedons may contain residuum from these rocks in the lower portion of the profile. Slope ranges from 10 to 40 percent. The average annual air temperature is about 6.1 degrees C and average annual precipitation is about 1,525 mm.

TAXONOMIC CLASS: Medial over loamy, amorphic over mixed, active, frigid Alfic Udivitrands

TYPICAL PEDON: Odonnell medial silt loam, forest; on a northwest-facing slope of 28 percent at 945 meters elevation. When described on August 19, 1986, the soil was moist throughout. (Colors are for dry soil unless otherwise stated.)

Oi--0 to 5 cm; slightly decomposed needles, leaves, twigs and bark.

Oe--5 to 8 cm; decomposed organic matter mixed with Mt. St. Helens volcanic ash. (combined thickness of Oi, Oe horizons - 0 to 8 cm)

A--8 to 18 cm; yellowish brown (10YR 5/4) medial silt loam, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and slightly plastic; common very fine, fine, medium, and coarse roots; common very fine and fine tubular and irregular pores; few fine and medium iron and manganese concretions; 5 percent fine gravel; neutral (pH 7.0); clear wavy boundary. (5 to 15 cm thick)

Bw--18 to 43 cm; light yellowish brown (10YR 6/4) 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, and few medium and coarse roots; many very fine and fine tubular and irregular pores; common fine and medium iron and manganese concretions; 5 percent fine gravel; neutral (pH 6.8); abrupt wavy boundary. (20 to 38 cm thick)

2E--43 to 48 cm; very pale brown (10YR 8/3) silt loam, pale brown (10YR 6/3) moist; moderate fine platy structure; hard, firm, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and fine tubular pores; few faint bleached silt coatings on faces of peds; 5 percent fine gravel; slightly acid (pH 6.5); clear wavy boundary. (0 to 25 cm thick)

2Bt/E--48 to 64 cm; mixed very pale brown (10YR 8/3) and pink (7.5YR 7/4) silt loam, pale brown (10YR 6/3) and brown (7.5YR 5/4) moist; moderate medium and coarse prismatic structure; very hard, very firm, moderately sticky and slightly plastic; common very fine and fine roots; common very fine tubular pores; many faint and common distinct clay films on faces of peds and lining pores; common faint bleached silt coatings on face of peds; 10 percent fine gravel; slightly acid (pH 6.5); clear irregular boundary. (0 to 56 cm thick)

2E/Btb--64 to 102 cm; yellow (10YR 8/6) tongues of silt loam, brownish yellow (10YR 6/6) moist; weak coarse angular blocky structure; hard, firm, slightly sticky and slightly plastic; interfingered with reddish yellow (7.5YR 7/6) silty clay loam, strong brown (7.5YR 5/6) moist; moderate medium and coarse prismatic structure; very hard, very firm, moderately sticky and moderately plastic; the E material occupies about 70 percent of the horizon in tongues from 10 to 15 cm thick; few very fine and fine roots; common very fine and fine tubular pores; many faint and common distinct clay films on faces of peds and lining pores of Bt material; 5 percent fine gravel; strongly acid (pH 5.5) in the E material and slightly acid (pH 6.5) in the Bt material; clear wavy boundary. (0 to 43 cm thick)

2Btb--102 to 135 cm; mixed reddish yellow (5YR 7/6) and reddish yellow (7.5YR 7/6) silty clay loam, yellowish red (5YR 5/6) and strong brown (7.5YR 5/6) moist; moderate coarse angular blocky structure; very hard, very firm, moderately sticky and moderately plastic; few very fine roots; few very fine and fine tubular pores; common faint clay films on faces of peds and lining pores; 5 percent fine gravel; moderately acid (pH 5.8); abrupt irregular boundary. (15 to 99 cm thick)

2BC--135 to 160 cm; mixed yellow (10YR 8/6) and reddish yellow (7.5YR 7/6) silt loam, yellow (10YR 7/6) and strong brown (7.5YR 5/6) moist; weak coarse subangular blocky structure; hard, firm, slightly sticky and slightly plastic; few very fine roots; few very fine and fine tubular pores; few faint clay films on faces of peds and lining pores; 5 percent gravel and 5 percent cobbles; very strongly acid (pH 5.0).

TYPE LOCATION: Shoshone County, Idaho; approximately 17.5 miles east of Clarkia, about 610 meters north and 305 meters east of the southwest corner of sec. 35, T. 42 N., R. 4 E. Latitude - 46 degrees, 56 minutes, 19 seconds North. Longitude - 115 degrees, 55 minutes, 44 seconds West; UTM 11T easting 581524.7, northing 5198899; USGS Pinchot Butte quadrangle.

RANGE IN CHARACTERISTICS:
Soil moisture - usually dry for 10 to 20 consecutive days mid-August to September, moist in the fall through early summer (Udic moisture regime)
Average annual soil temperature - 3.9 to 7.2 degrees C
Average summer soil temperature - 8.9 to 10.0 degrees C with an O horizon Solum thickness - greater than 150 cm
Depth to perched water table - 46 to 76 cm, February to April

Volcanic ash mantle - 35 to 46 cm thick*
*Volcanic glass content in the 0.02 to 2.0 mm fraction - 15 to 60 percent
* Ammonium oxalate extractable Al plus 1/2 Fe - 1.0 to 2.7 percent
*Phosphate retention - 55 to 95 percent
*15-bar water retention on air dried samples - 7 to 12 percent

A horizon
Hue - 7.5YR to 10YR dry or moist
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 3 to 4 dry, 2 to 4 moist
Texture - medial silt loam, medial loam
Clay content - 8 to 12 percent
Rock fragments - 0 to 5 percent gravel
Bulk density - 0.65 to 0.90 g/cc
Reaction - moderately acid to neutral

Bw horizon
Hue - 7.5YR or 10YR dry or moist
Value - 4 to 6 dry, 3 or 4 moist
Chroma - 4 to 6 dry or moist
Texture - medial silt loam, medial loam
Clay content - 8 to 14 percent
Rock fragments - 0 to 5 percent gravel
Bulk density - 0.65 to 1.00 g/cc
Reaction - moderately acid to neutral

2E horizon (absent in some profiles)
Hue - 7.5YR or 10YR dry or moist
Value - 6 to 8 dry and 3 to 6 moist
Chroma - 2 to 4 dry, 3 or 4 moist
Texture - silt loam, loam
Clay content - 16 to 24 percent
Rock fragments - 0 to 5 percent gravel
Reaction - moderately acid to slightly acid

2E/B horizon (present in some profiles)
Hue - 10YR to 7.5YR dry or moist
Value - E portion - 6 dry, 3 or 4 moist
B portion - 4 to 6 dry, 3 to 4 moist
Chroma - E portion - 3 dry, 4 to 6 moist
B portion - 4 dry, 4 to 6 moist
Texture - silt loam
Clay content - E portion - 16 to 18 percent
B portion - 23 to 26 percent
Rock fragments - 0 to 5 percent gravel
Reaction - moderately acid to slightly acid

2Bt/E horizon
Hue - 7.5YR or 10YR dry or moist
Value - B portion - 4 to 6 dry, 3 to 5 moist
E portion - 5 to 8 dry, 3 to 6 moist
Chroma - B portion - 3 or 4 dry, 4 to 6 moist
E portion - 3 or 4 dry, 4 to 6 moist
Texture - B portion - silt loam or silty clay loam
E portion - silt loam or loam
Clay content - B portion - 20 to 30 percent
E portion - 17 to 20 percent
Rock fragments - 0 to 10 percent gravel
Base saturation - 35 to 50 percent
Reaction - moderately acid or slightly acid

2E/Btb horizon (absent in some profiles)
Hue - 7.5YR or 10YR dry or moist
Value - 4 to 8 dry, 3 or 6 moist
Chroma - 3 to 6 dry and moist
Rock fragments - 0 to 10 percent fine gravel
Clay content - 16 to 30 percent
Base saturation - 35 to 50 percent
Reaction - strongly acid to slightly acid

2Btb horizon
Hue - 2.5YR to 10YR dry or moist
Value - 4 to 8 dry and 3 to 6 moist
Chroma - 2 to 8 dry, 3 to 6 moist
Texture - silty clay loam, loam, silt loam, clay loam or silty clay
Rock fragments - 0 to 10 percent gravel
Clay content - 19 to 40 percent
Base saturation - 35 to 50 percent
Reaction - very strongly acid to slightly acid

2BC or 2C horizons - (absent in some profiles)
Hue - 10YR to 5YR dry or moist
Value - 5 to 8 dry, 4 to 7 moist
Chroma - 4 to 6 dry and moist
Texture - silt loam, loam, fine sandy loam, loamy sand, sandy loam
Clay content - 5 to 20 percent
Rock fragments - 0 to 35 percent gravel, 0 to 20 percent cobbles, 0 to 40 percent total fragments
Reaction - very strongly acid or strongly acid

COMPETING SERIES:
Lado - have 3Bt horizons and do not have albic materials within 100 cm of the soil surface
Lostpete - do not have buried horizons
Povo - have 3Bt horizons and do not have albic materials within 100 cm of the soil surface

GEOGRAPHIC SETTING:
Landforms - hillslopes, benches and relict stream terraces
Elevations - 490 to 1,340 meters
Slopes - 10 to 40 percent
Parent material - formed in mixed materials consisting of loess, colluvium and alluvium derived from anorthosite, schist, and gneiss bedrock with a thick mantle of volcanic ash. Some pedons have residuum from these rocks in the lower portion.
Climate - cool, humid with warm, moist summers and cold, wet winters
Mean annual precipitation - 890 to 1,650 mm
Mean annual air temperature - 3.3 to 7.2 degrees C.
Frost-free season - 50 to 110 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Floodwood, Garveson, and Keeler soils. Floodwood soils are on north, east and west-facing convex slopes of foothills and mountains, and are well drained. Keeler soils are on south-facing concave slopes of foothills and mountains, and are well drained and do not have a volcanic ash mantle. Garveson soils are on north, east, and west-facing convex slopes of canyonsides, and are ashy over sandy or sandy-skeletal and do not have argillic horizons.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained; rapid to very rapid runoff; slow saturated hydraulic conductivity.

USE AND VEGETATION: These soils are used for timber production, recreation, watershed, and wildlife habitat. Potential natural vegetation is mainly western redcedar, western white pine, grand fir, Douglas-fir, and western larch, with an understory of common ladyfern, queencup beadlily, wild ginger, starry false-Solomons-seal, American trailplant, sweet-scented bedstraw, oneleaf foamflower, longtube twinflower, piper anemone, Oregon fairybells, and oakfern.

DISTRIBUTION AND EXTENT: Northern Idaho. This soil is not extensive. MLRA 43A.

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

SERIES ESTABLISHED: Shoshone County, Idaho, 1993.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 18 cm (Oi, Oe, A horizons)
Cambic horizon - the zone from 18 to 43 cm (Bw horizon)
Albic horizon - the zone from 43 to 48 cm (E horizon)
Argillic horizon - the zone from 48 to 135 cm (2Bt/E, 2E/Btb, 2Btb horizons)
Volcanic ash mantle - the zone from 8 to 43 cm (A, Bw horizons)
Particle-size control section - the zone from 8 to 108 cm (A, Bw, 2E, 2Bt/E, 2E/Btb, part of the 2Btb horizon)

Additional data: This series has laboratory data - S95ID-035-006 (96P23), Clearwater county, Idaho; by NSSL, Lincoln, NE.

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National Cooperative Soil Survey
U.S.A.