LOCATION NEVA ID

Established Series
Rev. BDG-JAL-EMM
06/2013

NEVA SERIES

The Neva series consists of very deep, well drained soils on mountain slopes and ridges. They formed in a mixture of loess and material weathered from granite, gneiss, quartzite or schist with a thin mantle of volcanic ash. Saturated hydraulic conductivity is moderately high. Slope ranges from 5 to 70 percent. The average annual temperature is about 42 degrees F. and the average annual precipitation is about 40 inches.

TAXONOMIC CLASS: Fine-loamy, isotic, frigid Andic Haploxeralfs

TYPICAL PEDON: Neva ashy silt loam, forested, on a southeast-facing slope of 46 percent at 3,700 feet elevation. (Colors are for dry soil unless otherwise stated.)

Oi--0 to 0.5 inch; partially decomposed needles and twigs.

Oe--0.5 to 1 inch; decomposed needles and twigs. (Combined thickness of the O horizons is 1 to 2 inches)

A--1 to 4 inches; dark grayish brown (10YR 4/2) ashy silt loam, very dark brown (7.5YR 2.5/2) moist; weak very fine and fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine and few medium roots throughout; few very fine tubular pores; slightly acid (pH 6.3); abrupt smooth boundary. (2 or 4 inches thick)

Bw1--4 to 8 inches; light yellowish brown (10YR 6/4) ashy silt loam, brown (10YR 4/3) moist; weak fine and medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and fine roots throughout; few very fine and fine tubular pores; slightly acid (pH 6.5); clear smooth boundary.

Bw2--8 to 13 inches; brownish yellow (10YR 6/6) ashy silt loam, dark brown (7.5YR 3/4) 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 throughout; few very fine tubular pores; slightly acid (pH 6.5); abrupt wavy boundary. (Combined thickness of the Bw horizons is 6 to 10 inches)

2BE--13 to 25 inches; light yellowish brown (10YR 6/4) loam, dark yellowish brown (10YR 4/4) moist; weak medium and coarse subangular blocky structure parting to moderate fine and medium subangular blocky; moderately hard, friable, nonsticky and moderately plastic; common very fine and fine roots between peds and common medium roots throughout; common very fine and fine and few coarse tubular pores; 8 percent faint silt coats on faces of peds and in pores; 5 percent fine mica flakes; 2 percent gravel; slightly acid (pH 6.1); abrupt smooth boundary. (0 to 19 inches thick)

2Bt1--25 to 35 inches; light brown (7.5YR 6/4) loam, strong brown (7.5YR 4/6) moist; moderate fine and medium subangular blocky structure; moderately hard, friable, slightly sticky and moderately plastic; common very fine and few fine roots between peds; common very fine and fine and few coarse tubular pores; 5 percent prominent clay films on faces of peds, 5 percent distinct clay films in pores and 10 percent distinct silt coats on faces of peds and in pores; 5 percent fine mica flakes; 2 percent gravel; moderately acid (pH 6.0); clear wavy boundary.

2Bt2--35 to 50 inches; 70 percent light yellowish brown (10YR 6/4) loam, strong brown (7.5YR4/6) moist and 30 percent yellowish brown (10YR 5/4) sandy clay loam, brown (7.5YR 4/4) moist; moderate medium and coarse subangular blocky structure; moderately hard, friable, slightly sticky and moderately plastic; common very fine and few fine roots between peds; common very fine tubular pores; 15 percent prominent clay films on faces of peds and in pores; 5 percent fine mica flakes; 3 percent gravel; moderately acid (pH 5.8). (Combined thickness of 2Bt horizons is 15 to 50 inches)

2BC--50 to 56 inches; very pale brown (10YR 7/4) loam, dark yellowish brown (10YR 4/6) moist; weak fine and medium subangular blocky structure; moderately hard, friable, nonsticky and slightly plastic; common very fine roots between peds; common very fine tubular pores; 10 percent prominent clay films in pores; 5 percent fine mica flakes; 5 percent gravel; moderately acid (pH 5.7); clear wavy boundary. (0 to 9 inches thick)

2C--56 to 62 inches; very pale brown (10YR 7/4) coarse sandy loam, yellowish brown (10YR 5/4) moist; massive; slightly hard, friable, nonsticky and nonplastic; few very fine roots throughout; 5 percent fine mica flakes; 8 percent gravel; moderately acid (pH 5.6).

TYPE LOCATION: Clearwater County, Idaho; about 7 miles east of Helmer, Idaho; about 1,400 feet north and 2,400 feet west of the southeast corner of Sec. 22, T40N, R1E; Latitude - 46 degrees, 47 minutes, 35 seconds North; Longitude - 116 degrees, 19 minutes, 8 seconds West; USGS McGary Butte Quadrangle

RANGE IN CHARACTERISTICS:

Soil moisture - Usually dry for 45 to 70 consecutive days, moist November through mid-July, dry mid-July to October. (Xeric moisture regime)
Average annual soil temperature - 41 to 46 degrees F. (Frigid temperature regime)
Depth to weathered bedrock - greater than 60 inches
Volcanic ash thickness - 10 to 13 inches

A horizon
Value - 4 or 5 dry
Chroma - 2 to 6 dry, 2 or 3 moist
Clay content - 5 to 10 percent
Rock fragments - 0 to 3 percent gravel
Reaction - 5.8 to 6.7
Volcanic glass content - 15 to 65 percent
Acid-oxalate extractable Al+1/2Fe - 1.2 to 2.25 percent
Bulk density - 0.60 to 0.95 g/cc

Bw horizon
Value - 5 or 6 dry
Chroma - 4 or 6 dry
Clay content - 8 to 10 percent
Rock fragments - 0 to 3 percent gravel
Reaction - 5.6 to 6.8
Volcanic glass content - 15 to 65 percent
Acid-oxalate extractable Al+1/2Fe - 1.2 to 2.35 percent
Bulk density - 0.70 to 1.2 g/cc

2EB or BE horizons (present in some pedons)
Value - 5 or 6 dry, 3 to 5 moist
Texture - loam or silt loam
Clay content - 15 to 26 percent
Rock fragments - 2 to 15 percent gravel
Reaction - 5.0 to 6.5

2E/B or 2B/E horizons (present in some pedons)
B part:
Hue - 7.5YR or 10YR moist
Value - 5 or 6 dry, 3 or 4 moist
Textures - silt loam or loam
Clay content - 25 to 26 percent
E part:
Hue - 7.5YR or 10YR dry or moist
Value - 6 or 7 dry, 3 or 4 moist
Chroma - 3 or 4 dry
Textures - silt loam or loam
Clay content - 15 to 21 percent
Rock fragments - 2 to 10 percent gravel, 0 to 20 percent cobbles, 2 to 30 percent total rock fragment content (fragments often occur as a stoneline)
Reaction - very strongly acid to slightly acid

2Bt horizons
Hue - 5YR to 10YR dry, 5YR or 7.5YR moist
Value - 5 or 6 dry, 3 to 5 moist
Chroma - 4 to 8 dry or moist
Texture - loam, sandy clay loam or silty clay loam
Clay content - 16 to 28 percent
Rock fragments - 2 to 15 percent gravel
Reaction - 5.0 to 6.3

2BC horizon (present in some pedons)
Hue - 7.5YR ro 10YR moist
Value - 6 or 7 dry
Chroma - 4 to 6 dry
Texture - loam or sandy clay loam
Clay content - 10 to 20 percent
Rock fragments - 2 to 40 percent gravel, 0 to 5 percent cobbles, 2 to 45 percent total rock fragment content
Reaction - 5.2 to 6.3

2C horizon
Hue - 7.5YR or 10YR dry or moist
Value - 6 or 7 dry
Chroma - 4 to 8 dry, 6 or 8 moist
Textures - loam or coarse sandy loam
Clay content - 5 to 22 percent
Rock fragments - 2 to 50 percent gravel, 0 to 5 percent cobbles, 2 to 55 percent total rock fragment content
Reaction - 5.0 to 6.3

COMPETING SERIES:

Fan Lake soils: have an E horizon and fragic properties at a depth of 20 to 40 inches

Fugawee soils: are moderately deep to a paralithic contact

Henneway soils: are deep to a lithic contact

Tahand soils: are deep to a paralithic contact

GEOGRAPHIC SETTING: Neva soils are on mountain slopes and ridges. Slopes range from 5 to 70 percent. These soils formed in a mixture of loess and material weathered from granite, quartzite, gneiss or schist with a thin mantle of volcanic ash. Elevations are 2,700 to 4,200 feet (823 to 1280 meters). The average annual temperature ranges from 40 to 46 degrees F., with an average annual precipitation of 30 to 45 inches (762 to 1143 mm). The frost-free period ranges from 80 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Noil, Brequito, Brodeer and Carlinton series. Noil soils are loamy-skeletal and occur on steep south to west facing mountain slopes. Brequito and Brodeer soils have a udic moisture regime and occur on mountain slopes and ridges. Carlinton soils have a fragipan and occur on hills on loess covered basalt plateaus.

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, recreation, and watershed. Potential natural vegetation is mainly grand fir, Douglas-fir, western white pine and ponderosa pine with an understory of mallow ninebark, creambush oceanspray, common snowberry, Columbia brome, American trailplant, baldhip rose, heart leaf arnica, goldthread, Pipers anemone and bracken fern.

DISTRIBUTION AND EXTENT: North-central Idaho. This soil is 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:

Ochric epipedon - The zone from the mineral soil surface to 4 inches (A horizon).

Cambic horizon - The zone from 4 inches to 13 inches (Bw1 and Bw2 horizons).

Argillic horizon - The zone from 25 to 56 inches (2Bt1, 2Bt2 and 2BC horizons).

Andic feature - the zone from the mineral soil surface to 13 inches (A and AB horizons).

Particle-size control section - 25 to 45 inches (2Bt1 and part of 2Bt2 horizon).

The ranges in values listed under the A and Bw horizons for Volcanic glass content, Acid-oxalate extractable Al+1/2Fe, and bulk density are estimates only.

National Cooperative Soil Survey
U.S.A.