LOCATION KORELL MT+ND
Established Series
Rev. JAL-EMM
01/2013
KORELL SERIES
The Korell series consists of very deep, well drained soils formed in alluvium. These soils are on flood plains. Slopes are 0 to 8 percent. Mean annual precipitation is about 14 inches and mean annual temperature is about 43 degrees F.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Fluventic Haplustolls
TYPICAL PEDON: Korell loam in irrigated cropland (colors are for dry soil unless noted otherwise).
Ap--0 to 7 inches; dark gray (10YR 4/1) loam, black (10YR 2/1) moist; moderate medium and fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; slightly effervescent; slightly alkaline (pH 7.8); abrupt smooth boundary.
A2--7 to 12 inches; dark gray (10YR 4/1) loam, black (10YR 2/1) moist; weak medium prismatic structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine tubular and interstitial pores; slightly effervescent; slightly alkaline (pH 7.8); clear smooth boundary. (combined thickness of the A horizons is 7 to 15 inches)
Bw1--12 to 24 inches; light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; weak medium and coarse angular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; common very fine roots; many very fine tubular and interstitial pores; disseminated lime, strongly effervescent; strongly alkaline (pH 8.8); clear smooth boundary. (10 to 20 inches thick)
Bw2--24 to 34 inches; light brownish gray (10YR 6/2) silt loam, grayish brown (10YR 5/2) moist; weak medium angular blocky structure; slightly hard, friable, moderately sticky and slightly plastic; few very fine roots; many very fine tubular and interstitial pores; disseminated lime, strongly effervescent; strongly alkaline (pH 8.8); clear smooth boundary. (combined thickness of the Bw horizons is 7 to 20 inches thick)
BCk--34 to 60 inches; light brownish gray (2.5Y 6/2) stratified silt loam and loam, grayish brown (2.5Y 5/2) moist; with few fine prominent strong brown (7.5YR 5/6) relict mottles; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine tubular and interstitial pores; few fine seams and masses of lime; strongly effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Lewis and Clark County, Montana; 1,100 feet north and 50 feet east of the SW corner of sec. 11, T. 15 N., R. 3 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 42 to 47 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 7 to 15 inches.
The organic carbon decreases irregularly with depth.
An Ab horizon up to 6 inches thick is allowed.
A horizons
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 1 or 2
Texture: loam or silt loam
Clay content: 18 to 27 percent
Reaction: pH 7.4 to 7.8
Bw horizons
Hue: 10YR and 2.5Y
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 or 3
Texture: loam or silt loam
Clay content: 18 to 27 percent
Sodium adsorption ratio (SAR): 5 to 13
Reaction: pH 7.9 to 9.0
BCk, Bk, or C horizons
Hue: 10YR and 2.5Y
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 1, 2 or 3
Texture: loam, fine sandy loam, silt loam or clay loam
Clay content: 18 to 30 percent
Calcium carbonate equivalent: 5 to 15 percent
Sodium adsorption ratio (SAR): 5 to 13
Electrical conductivity (EC): 0 to 4 mmhos/cm
Reaction: pH 7.9 to 9.0
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING:
Landform - flood plains.
Slope - 0 to 8 percent.
Elevation - 3,500 to 5,400 feet, down to 1600 feet in North Dakota.
Parent material - alluvium.
Climate - long, cold winters; moist springs; warm, summers.
Mean annual precipitation - 12 to 19 inches, most of which comes in the spring and early summer. Precipitation ranges to 18 inches in North Dakota
Mean annual air temperature - 39 to 45 degrees F.
Frost-free period - 80 to 135 days.
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Korell soils are used mainly for irrigated and nonirrigated cropland. The native vegetation is mainly bluebunch wheatgrass, green needlegrass, needleandthread, western wheatgrass, and prairie junegrass.
DISTRIBUTION AND EXTENT: Korell soils are inextensive in the valleys of western Montana. MLRA 43B, 44B, 46 and 54.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Lewis and Clark County Area, Montana, 1991; proposed in Lewis and Clark County, Montana, 1990.
REMARKS: Soil Interpretation Record: MT1258.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 12 inches (Ap and A2 horizons);
Cambic horizon - from 12 to 24 inches (Bw horizon);
Accumulation of lime - from 34 to 70 inches (BCk horizon);
Particle size control section - from 10 to 40 inches (A2, Bw1, Bw2, and part of BCk horizons).
Korell soils have an irregular decrease in organic carbon.
Korell soils have a frigid temperature regime and an ustic moisture regime.
National Cooperative Soil Survey
U.S.A.