LOCATION NORWIDGE ID

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

NORWIDGE SERIES

The Norwidge series consists of very deep, well drained soils formed in loess and reworked loess with a mantle of volcanic ash. They are on mountain slopes, hills, plateaus and structural benches. Saturated hydraulic conductivity is moderately high and slopes range from 5 to 40 percent. The average annual precipitation is about 36 inches and the average annual temperature is about 42 degrees F.

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

TYPICAL PEDON: Norwidge medial silt loam, forested on a 10 percent slope at 2,950 feet elevation. Aspect is southeast. When described on August 3, 1994, the profile was moist below 41 inches. (Colors are for dry soil unless otherwise noted.)

Oi--0 to 0.5 inches; slightly decomposed needles, twigs and leaves.

Oe--0.5 to 1 inch; decomposed needles, twigs and leaves. (0.5 to 4 inches thick)

A-- 1 to 3 inches; brown (7.5YR 4/3) medial silt loam, very dark brown (7.5YR 2.5/2) moist; weak fine granular structure; soft, very friable, nonsticky and slightly plastic; many very fine and fine and common medium roots; many very fine and fine, and common medium and coarse irregular pores; 5 percent fine iron-manganese concretions; slightly acid (pH 6.2); abrupt wavy boundary. (0 to 5 inches thick)

Bw1--3 to 9 inches; yellowish brown (10YR 5/4) medial silt loam, dark brown (7.5YR 3/4) moist; weak very fine subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and slightly plastic; many very fine and fine, common medium, coarse and very coarse roots; many very fine, common fine and medium, and few coarse irregular pores; moderately acid (pH 6.0); clear wavy boundary.

Bw2--9 to 17 inches; yellowish brown (10YR 5/4) medial silt loam, dark brown (7.5YR 3/4) moist; weak very fine subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and slightly plastic; many very fine and fine, common medium, coarse and very coarse roots; many very fine, common fine and medium, and few coarse irregular pores; moderately acid (pH 6.0); abrupt wavy boundary. (Bw horizons 10 to 15 inches)

2Bt/E1--17 to 27 inches; B part - brown (7.5YR 5/4) silt loam, dark brown (7.5YR 3/4) moist; E part - pale brown (10YR 6/3) silt loam, light yellowish brown (10YR 6/4) moist; weak medium prismatic structure parting to strong medium and coarse subangular blocky; hard, firm, slightly sticky and slightly plastic; common very fine and fine and few medium roots between peds; many very fine and common fine tubular and common very fine irregular pores; common faint dark brown (7.5YR 3/4) clay films on faces of peds and in pores; 5 percent fine iron-manganese concretions; slightly acid (pH 6.2); gradual wavy boundary.

2Bt/E2--27 to 33 inches; B part - light yellowish brown (10YR 6/4) silt loam, dark yellowish brown (10YR 3/4) moist; E part - pale brown (10YR 6/3) silt loam, dark yellowish brown (10YR 4/4) moist; weak medium prismatic structure parting to strong medium and coarse subangular blocky; hard, firm, slightly sticky and slightly plastic; common very fine and fine roots between peds; many very fine, common fine and few medium tubular pores; many faint dark yellowish brown (10YR 3/4) clay films on faces of peds and in pores; 2 percent fine iron manganese concretions; moderately acid (pH 6.0); gradual wavy boundary. (2Bt/E horizons 0 to 40 inches)

2Btx1--33 to 42 inches; yellowish brown (10YR 5/4) silty clay loam, dark yellowish brown (10YR 3/4) moist; moderate medium prismatic structure parting to strong medium and coarse subangular blocky; very hard, firm, moderately sticky and moderately plastic; common very fine and few fine roots between peds; many very fine, common fine and few medium tubular pores; many distinct dark yellowish brown (10YR 3/4) clay films on faces of peds and in pores; many faint very pale brown (10YR 7/3) uncoated silt grains on faces of peds and in pores; 2 percent fine iron-manganese concretions; 5 percent of peds are brittle when moist; moderately acid (pH 6.0); gradual wavy boundary.

2Btx2--42 to 56 inches; yellowish brown (10YR 5/4) silt loam, dark yellowish brown (10YR 3/4) moist; moderate medium prismatic structure parting to strong medium and coarse subangular blocky; very hard, firm, moderately sticky and moderately plastic; common very fine and few fine roots between peds; many very fine and few fine and medium tubular pores; many faint dark yellowish brown (10YR 3/4) moist clay films on faces of peds and in pores; many faint light yellowish brown (10YR 6/4) moist uncoated silt grains on faces of peds and in pores; 5 percent fine iron-manganese concretions; 10 percent of peds are brittle when moist; moderately acid (pH 6.0); clear wavy boundary. (3Bt horizons 0 to 36 inches)

2Btxb1--56 to 67 inches; yellowish brown (10YR 5/4) silt loam, dark brown (7.5YR 3/4) moist; moderate medium and coarse prismatic structure; very hard, very firm, moderately sticky and moderately plastic; common very fine and fine roots between peds; many very fine and few fine and medium tubular pores; many distinct dark yellowish brown (10YR 3/4) moist clay films on faces of peds and in pores; few faint pale brown (10YR 6/3) moist uncoated silt grains of faces of peds and in pores; 10 percent fine iron-manganese concretions; 30 percent of peds are brittle when moist; moderately acid (pH 6.0); gradual wavy boundary. (11 to 15 inches thick)

2Btxb2--67 to 81 inches; yellowish brown (10YR 5/4) silty clay loam, dark brown (7.5YR 3/4) moist; moderate medium and coarse prismatic structure; very hard, very firm, moderately sticky and moderately plastic; few very fine and fine roots between peds; many very fine and few fine tubular pores; many faint dark yellowish brown (10YR 3/4) moist clay films on faces of peds and in pores; few faint pale brown (10YR 6/3) moist uncoated silt grains on faces of peds and in pores; 10 percent fine iron-manganese concretions; 40 percent of peds are brittle when moist; moderately acid (pH 6.0).

TYPE LOCATION: Clearwater County, Idaho; about 10 miles north of Ahsahka, Idaho; about 200 feet south and 2,500 feet east of the northwest corner of sec. 10, T. 38N., R. 1E. Latitude - 46 degrees, 39 minutes, 23 seconds North; Longitude - 116 degrees, 19 minutes, 9 seconds West. USGS Aldermand Ridge Quadrangle.

RANGE IN CHARACTERISTICS:

Average annual soil temperature - 39 to 45 degrees F. (frigid temperature regime)
Soil moisture - usually moist year round and not dry for 45 or more consecutive days from June to October. (udic moisture regime)
Depth to fragic characteristics - 30 to 57 inches.

Thickness of volcanic ash mantle - 14 to 16 inches
Volcanic glass content - 15 to 65 percent
Acid-oxalate Al plus 1/2 Fe - 1.3 to 2.7 percent
Phosphate retention - 55 to 95 percent
15 bar water retention on air dried samples - 12 to 20 percent (by weight)

A horizon
Hue - 7.5YR or 10YR dry or moist
Value - 3 to 6 dry and 2.5 or 3 moist
Chroma - 2 to 4 dry or moist
Clay content - 8 to 10 percent
Reaction - 5.6 to 6.9
Iron-manganese concretions - 3 to 5 percent
Bulk density - 0.60 to 0.95 g/cc

Bw horizons
Hue - 7.5YR or 10YR dry or moist
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 4 to 6 dry or moist
Clay content - 8 to 10 percent
Reaction - 5.6 to 6.9
Bulk density - 0.65 to 0.95

2E horizon present in some pedons.

2Bt/E, 2E, 2E/B horizons (when present)
B part
Hue - 7.5YR or 10YR dry or moist
Value - 4 to 6 dry and 3 or 4 moist
Chroma - 3 to 6 dry, 3 or 4 moist
Texture - silt loam or silty clay loam
Clay content - 18 to 32 percent
E part
Hue - 7.5YR or 10YR dry or moist
Value - 6 or 7 dry and 4 to 7 moist
Chroma - 2 to 4 dry, 3 or 4 moist
Clay content - 15 to 20 percent
Rock fragments - 0 to 2 percent gravel
Reaction - 5.1 to 6.2

2Btx horizons
Hue - 7.5YR or 10YR dry or moist
Value - 4 to 6 dry and 3 to 5 moist
Chroma - 3 or 4 dry or moist
Texture - silt loam or silty clay loam
Clay content - 18 to 30 percent
Rock fragments - 0 to 5 percent gravel
Reaction - 5.1 to 6.0

2Btxb, horizons
Hue - 7.5YR or 10YR dry or moist
Value - 4 to 6 dry and 3 to 5 moist
Chroma - 3 or 4 dry, 3 to 6 moist
Texture - silt loam or silty clay loam
Clay content - 22 to 40 percent
Rock fragments - 0 to 10 percent gravel
Consistence - 15 to 60 percent of horizon is brittle moist and extremely hard dry
Reaction - 5.1 to 6.0

COMPETING SERIES: This is the Elkberry series.

Elkberry soils: very deep: do not have fragic properties

GEOGRAPHIC SETTING: Norwidge soils are on mountain slopes, hills, plateaus and structural benches at elevations of 2,000 to 3,600 feet (610 to 1098 meters) with slopes of 5 to 40 percent. These soils formed in loess and reworked loess with a thick mantle of volcanic ash. The average annual temperature is 38 to 46 degrees F. and the average annual precipitation is 31 to 55 inches (787 to 1397 mm). The frost free season is 50 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dworshak, Grangemont, Threebear and Kauder soils. Dworshak soils do not have fragic characteristics. Grangemont soils have ash mantles less than 14 inches thick. Threebear and Kauder soils have fragipans. All these soils are on hills.

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 and watershed. Potential natural vegetation is western redcedar, grand fir, Douglas-fir, western larch, and western white pine with an understory of queencup beadlily, longtube twinflower, oneleaf foam flower, goldthread, starry false Solomons-seal, myrtle pachystima, common snowberry and Columbia brome.

DISTRIBUTION AND EXTENT: North central Idaho; Norwidge soils are moderately extensive. MLRA 43A.

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 1 to 3 inches (A horizon)

Volcanic ash mantle - The zone from 1 to 17 inches (A, Bw1 and Bw2 horizons)

Cambic horizon - The zone from 3 to 17 inches (Bw1 and Bw2 horizons)

Argillic horizon - The zone from 17 to 81 inches (2Bt/E1, 2Bt/E2, 2Btx1, 2Btx2, 2Btxb1 and 2Btxb2 horizons)

Particle size control section - The zone from 1 to 41 inches (A, Bw1, Bw2, 2Bt/E1, 2Bt/E2 and part of the 3Bt1 horizon)

The ranges of values listed under the Range in Characteristics for the soil properties Bulk density, Volcanic glass content, Acid-oxalate Al +1/2 Fe, Phosphate retention and 15-bar water retention are estimates only.

Additional data: This series has laboratory data - S95ID-035-003 (96P20); Clearwater county, ID; NSSL, Lincoln, NE.

National Cooperative Soil Survey
U.S.A.