LOCATION NIARADA MTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Calcic Haploxerolls
TYPICAL PEDON: Niarada gravelly loam, pastureland (colors are for dry soil unless otherwise noted).
Ap--0 to 7 inches; very dark grayish brown (10YR 3/2) gravelly loam, very dark brown (10YR 2/2) moist; moderate medium granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; few pores; 25 percent gravel; neutral (pH 6.8); clear smooth boundary.
A--7 to 14 inches; dark grayish brown (10YR 4/2) very gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate medium blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots, common medium roots; few very fine and fine tubular pores; 35 percent gravel; neutral (pH 7.0); clear wavy boundary. (Combined A horizon thickness is 7 to 16 inches)
Bw--14 to 18 inches; pale brown (10YR 6/3) very gravelly loam, grayish brown (10YR 5/2) moist; moderate medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots, and common medium roots; few very fine and fine tubular pores; 50 percent gravel and 5 percent cobbles; neutral (pH 7.0); clear wavy boundary. (4 to 13 inches thick)
Bk1--18 to 29 inches; very pale brown (10YR 8/2) very gravelly loam, pale brown (10YR 6/3) moist; massive; very friable, slightly sticky and slightly plastic; common very fine and fine roots, and few medium roots; few fine and very fine tubular pores; 50 percent gravel and 5 percent cobbles; disseminated lime, common distinct coatings of lime on undersides and sides of gravel; violently effervescence; moderately alkaline (pH 8.4); gradual wavy boundary. (8 to 18 inches thick)
Bk2--29 to 60 inches; light gray (10YR 7/2) very gravelly loam, brown (10YR 5/3) moist; massive; soft, very friable, slightly sticky and slightly plastic; few fine and medium roots; 50 percent gravel and 5 percent cobbles; disseminated lime, common distinct coatings of lime covering gravel; violently effervescence; moderately alkaline (pH 8.4).
TYPE LOCATION: Lake County, Montana; 1,650 feet west and 40 feet north of the SE corner of sec. 6, T. 23 N., R. 21 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 43 to 47 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 7 to 20 inches.
Depth to Bk horizon - 12 to 40 inches.
Ap horizon
Value: 3, 4 or 5 dry; 2 or 3 moist
Chroma: 1 or 2
Clay content: 10 to 27 percent
Rock fragments: 15 to 50 percent--0 to 10 percent stones and cobbles; 15 to 40 percent gravel
Reaction: 6.1 to 7.8
A horizon
Value: 4 or 5 dry; 2 or 3 moist
Chroma: 2 or 3
Clay content: 15 to 27 percent
Rock fragments: 15 to 50 percent--0 to 15 percent stones and cobbles; 15 to 40 percent gravel
Reaction: 6.6 to 7.8
Bw horizon
Value: 5 or 6 dry; 3, 4, or 5 moist
Chroma: 2, 3, or 4
Texture: loam or silt loam
Clay content: 10 to 27 percent
Rock fragments: 35 to 70 percent--10 to 20 percent stones and cobbles; 25 to 55 percent gravel
Reaction: 6.6 to 7.8
Bk1 horizon
Value: 6, 7, or 8 dry; 4, 5 or 6 moist
Chroma: 2 or 3
Texture: loam or sandy loam
Clay content: 10 to 18 percent
Rock fragments: 35 to 65 percent--10 to 25 percent stones and cobbles, 25 to 50 percent gravel
Calcium carbonate equivalent: 15 to 35 percent
Reaction: 7.9 to 8.4
Bk2 horizon
Value: 6, 7, or 8 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: loam or sandy loam
Clay content: 10 to 18 percent
Rock fragments: 35 to 60 percent--10 to 25 percent stones and cobbles, 35 to 50 percent gravel
Calcium carbonate equivalent: 5 to 25 percent
Reaction: 7.9 to 8.4
COMPETING SERIES:
Buist (ID) - do not have a cambic horizon free of carbonates; have less than 10 percent clay in the lower Bk horizon; have hues yellower than 10YR.
Conneridge (ID) - has an R horizon at 20 to 40 inches.
Cooley (ID) has an AB horizon.
Dagan (UT) - has hues redder than 10YR.
Hondoho (ID) - are calcareous below th surface layer; have a mixed AB horizon.
Ireland (ID) - has an R horizon at 20 to 40 inches.
Jebo (UT) - has an R horizon at 20 to 40 inches.
Pedleford (ID) - has an R horizon at 20 to 40 inches.
Tuckerdowns (OR) - is calcareous in the lower part of the mollic epipedon; has more than 18 percent clay in the particle-size control section; do not have a cambic horizon that is noncalcareous.
GEOGRAPHIC SETTING:
Landform- stream terraces, dissected alluvial fans, hills, and moraines.
Elevation - 2,500 to 4,900 feet.
Slope - 0 to 60 percent.
Parent material - till, alluvium, colluvium and glacial drift.
Climate - long, cold winters; moist falls and springs; warm, dry summers.
Mean annual precipitation - 14 to 19 inches.
Mean annual temperature - 41 to 45 degrees F.
Frost-free period - 90 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS:
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Niarada soils are used for irrigated and dryland crops, pastureland, and rangeland. The potential native vegetation is mainly rough fescue, Idaho fescue, bluebunch wheatgrass, prairie junegrass, threadleaf sedge, forbs, and shrubs.
DISTRIBUTION AND EXTENT: Niarada soils are of moderate extent in intermountain valleys of western Montana. MLRA 44A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Lake County, Montana, 1991; proposed in Lake County, Montana, 1973.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 14 inches (Ap and A horizons)
Cambic horizon - 14 to 18 inches (Bw horizon)
Calcic horizon - 18 to 29 inches (Bk1 horizon).
Niarada soils have a frigid temperature regime and a xeric moisture regime.
ADDITIONAL DATA: Soil interpretation records MT0283 and MT0927.