LOCATION BARGAMIN ID

Established Series
Rev. GAH-BG-JAL
12/2022

BARGAMIN SERIES

The Bargamin series consists of very deep, well drained soils formed in a deep volcanic ash mantle over loess and highly weathered basalt. They are on hills on basalt plateaus. Permeability is slow and slopes range from 10 to 35 percent. The average annual precipitation is about 37 inches and the average annual air temperature is about 42 degrees F.

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

TYPICAL PEDON: Bargamin ashy silt loam, forested, on a 35 percent slope at 3,300 feet elevation. Aspect is northeast. When described on July 16, 1993, the soil was moist throughout. (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.

A--1 to 2 inches; yellowish brown (10YR 5/4) ashy silt loam, dark brown (7.5YR 3/4) moist; weak very fine and fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; many very fine and common fine and medium roots; many very fine and common fine irregular pores; slightly acid (pH 6.2); clear wavy boundary. (1 to 3 inches thick)

Bw1--2 to 8 inches; brownish yellow (10YR 6/6) ashy silt loam, dark brown (7.5YR 3/4) moist; weak very fine, fine and medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; many very fine and common fine, medium and coarse roots; many very fine and common fine irregular pores; moderately acid (pH 6.0); clear wavy boundary.

Bw2--8 to 17 inches; brownish yellow (10YR 6/6) ashy silt loam, dark brown (7.5YR 3/4) moist; weak very fine, fine and medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; many very fine, common fine and medium, and few coarse roots; many very fine and common fine irregular pores; moderately acid (pH 6.0); abrupt wavy boundary. (Combined thickness of Bw horizons is 11 to 15 inches)

2Bt1--17 to 29 inches; yellowish brown (10YR 5/4) silt loam, brown (7.5YR 4/4) moist; weak medium prismatic structure parting to moderate fine, medium and coarse subangular blocky; slightly hard, firm, moderately sticky and moderately plastic; common very fine and fine and few medium and coarse roots; many very fine and few fine tubular and common very fine and fine irregular pores; common faint clay films lining pores and on faces of peds; 5 percent fine rounded iron-manganese concretions; moderately acid (pH 5.8); gradual wavy boundary. (6 to 12 inches thick)

2Bt2--29 to 38 inches; light yellowish brown (10YR 6/4) silt loam, brown (7.5YR 4/4) moist; weak medium prismatic structure parting to strong fine and medium subangular blocky; hard, firm, moderately sticky and moderately plastic; common very fine and fine and few medium roots; many very fine and fine and few medium tubular and common very fine and fine irregular pores; common faint clay films lining pores and on faces of peds; common faint skeletans on vertical faces of peds; 5 percent fine rounded iron-manganese concretions; moderately acid (pH 5.8); clear wavy boundary. (6 to 9 inches thick)

3Bt3b--38 to 49 inches; brown (7.5YR 5/4) silty clay loam, reddish brown (5YR 4/4) moist; weak medium prismatic structure parting to strong very fine, fine and medium subangular blocky; very hard, friable, very sticky and very plastic; few very fine roots; common very fine tubular and common very fine and few fine and medium irregular pores; many distinct clay films lining pores and on faces of peds; few prominent dark reddish brown (5YR 3/2) moist iron-manganese stains on faces of peds; moderately acid (pH 5.6); gradual wavy boundary. (11 to 14 inches thick)

3Bt4b--49 to 61 inches; brown (7.5YR 4/4) silty clay, dark reddish brown (2.5YR 3/4) moist; weak medium prismatic structure parting to strong very fine, fine and medium subangular blocky; very hard, friable, very sticky and very plastic; few very fine roots; common very fine and few fine tubular and common very fine irregular pores; many distinct clay films lining pores and on faces of peds; 5 percent prominent dark reddish brown (5YR 2/2) moist iron-manganese stains on faces of peds; moderately acid (pH 5.6); gradual wavy boundary. (12 to 15 inches thick)

3Bt5b--61 to 65 inches; brown (7.5YR 4/4) silty clay, dark red (2.5YR 3/6) moist; moderate medium prismatic structure parting to strong fine and medium subangular blocky; very hard, firm, very sticky and very plastic; few very fine roots; common very fine and fine tubular and common very fine irregular pores; many distinct clay films lining pores and on faces of peds; 15 percent prominent dark reddish brown (5YR 2/2) moist iron-manganese stains on faces of peds; strongly acid (pH 5.4).

TYPE LOCATION: Clearwater County, Idaho; about 3.5 miles east of Grangemont, Idaho; about 100 feet south and 2,550 feet west of the northeast corner of sec. 28, T 37N., R 4E.; Latitude - 46 degrees, 31 minutes, 41 seconds North; Longitude - 115 degrees, 57 minutes, 29 seconds West. USGS Whiskey Butte Quadrangle.

RANGE IN CHARACTERISTICS:

Average annual soil temperature - 42 to 46 degrees F. Frigid temperature regime.
Soil moisture - usually moist and not dry for 45 or more consecutive days from June to October. Udic moisture regime.
Thickness of volcanic ash mantle - 14 to 17 inches
Volcanic glass content - 15 to 50 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 - 8 to 12 percent

A horizon
Hue - 7.5YR or 10YR
Value - 4 or 5 dry, 2.5 or 3 moist
Chroma - 3 to 6 dry, 2 to 4 moist
Reaction - strongly acid to neutral
Bulk density - 0.65 to 0.90 g/cc

Bw horizons
Hue - 7.5YR or 10YR dry, 5YR or 7.5YR moist
Value - 5 or 6 dry
Chroma - 4 through 6 dry
Reaction - moderately acid to neutral
Bulk density - 0.65 to 1.00 g/cc

2EB horizons (present in some pedons)
Hue - 5YR or 7.5YR
Value - 3 or 4 moist
Clay content - 18 to 24 percent
Reaction - strongly acid or moderately acid

2Bt horizons
Hue - 5YR to 10YR dry, 2.5YR to 7.5YR moist
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 3 to 6 moist
Texture - SIL, SICL
Clay content - 21 to 35 percent
Reaction - strongly acid to slightly acid

3Btb horizons
Hue - 2.5YR to 7.5YR
Value - 4 to 6 dry, 2.5 to 4 moist
Chroma - 4 to 8 dry, 3 to 6 moist
Texture - SICL or SIC
Clay content - 30 to 48 percent
Reaction - very strongly acid to moderately acid

COMPETING SERIES: These are the Berray, Bussel, Odonnell, Revling (T) and Tomodo (T) series. Berray soils have lamellae and less than 18 percent clay in the argillic horizon. Bussel soils have more than 30 percent rock fragments in the lower part of the argillic horizon. Odonnel soils are moderately well drained. Revling soils have mica flakes in the control section and do not have moist hue of 5YR or redder in the 3Btb. Tomodo soils have fragic properties in the subsoil.

GEOGRAPHIC SETTING: Bargamin soils are on hills at elevations of 2,200 to 3,400 feet with slopes of 10 to 35 percent. These soils formed in a deep volcanic ash mantle over loess and highly weathered basalt. The average annual temperature is 41 to 44 degrees F. and the average precipitation is 30 to 40 inches. The frost free season is 50 to 110 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dowper (T), Grangemont (T), Jaype (T), Placer (T) and the competing Revling (T) soils. All soils are on hills. Grangemont, Jaype and Placer soils have less than 14 inches of volcanic ash on the surface.

DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; slow permeability.

USE AND VEGETATION: These soils are used for timber production, livestock grazing, wildlife habitat, watershed, and recreation. Potential natural vegetation is western redcedar, grand fir, Douglas-fir, western larch, western white pine and lodgepole pine with an understory of queencup beadlily, longtube twinflower, coolwort foamflower, American trailplant, common beargrass, big blueberry, bunchberry dogwood, goldthread and, starry false Solomons-seal.

DISTRIBUTION AND EXTENT: North central Idaho. Bargamin soils are not extensive.

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

SERIES PROPOSED: Clearwater County, Idaho, 1994.

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

Ochric epipedon - The zone from 1 to 8 inches mixed (A and Bw1 horizons)

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

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

Argillic horizon - The zone from 17 to 65 inches (2Bt1, 2Bt2, 3Bt1b, 3Bt2b and 3Bt3b horizons)

Particle-size control section - The zone from 1 to 41 inches (A, Bw1, Bw2, 2Bt1, 2Bt2, and part of the 3Bt3b horizon)

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

National Cooperative Soil Survey
U.S.A.