LOCATION NIKAT MT
Established Series
REV. KTS-JJU-RJS
01/2012
NIKAT SERIES
The Nikat series consists of very deep well drained soils that formed in alluvium, slope alluvium or colluvium derived from limestone. These soils occur on alluvial fans, fan remnants, colluvial aprons, hills and mountain slopes. Slopes are 2 to 60 percent. Mean annual precipitation is about 480 mm and mean annual air temperature is about 3 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, carbonatic Ustic Calcicryolls
TYPICAL PEDON: Nikat gravelly loam, in rangeland on a 40 percent slope at an elevation of 2295 meters (colors are for dry soil unless otherwise noted).
A--0 to 15 cm; brown (10YR 5/3) gravelly loam, dark brown (10YR 3/3) moist; weak very fine and fine granular structure; slightly hard, very friable, nonsticky and nonplastic; many very fine, fine and medium roots; many very fine irregular pores; 20 percent gravel and 5 percent cobbles; finely disseminated calcium carbonate; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (8 to 40 cm thick)
Bk1--15 to 33 cm; pale brown (10YR 6/3) gravelly loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; many very fine and fine, and few medium roots; many very fine tubular and irregular pores; 25 percent gravel and 5 percent cobbles; finely disseminated calcium carbonate, 5 percent soft masses of calcium carbonate, and 75 percent fine distinct irregular calcium carbonate nodules on bottom of rock fragments; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (10 to 50 cm thick)
Bk2--33 to 69 cm; pale brown (10YR 6/3) very gravelly loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; few very fine and fine roots; many very fine irregular pores; 40 percent gravel and 5 percent cobbles; finely disseminated calcium carbonate, 10 percent soft masses of calcium carbonate, and 60 percent medium distinct irregular calcium carbonate nodules on rock fragments; violently effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (10 to 50 cm thick)
Bk3--69 to 152 cm; very pale brown (10YR 7/3) extremely gravelly loam, pale brown (10YR 6/3) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; few very fine roots; common very fine irregular pores; 50 percent gravel and 10 percent cobbles; finely disseminated calcium carbonate, 5 percent soft masses of calcium carbonate, and 60 percent medium distinct irregular calcium carbonate nodules on rock fragments; violently effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Beaverhead County, Montana; located about 100 feet west and 2100 feet north of the southeast corner of sec. 17 , T. 13S, R 10W; Dixon Mountain topographic quadrangle; UTM 12T, 354540e, 4951385n, NAD 83.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 1 to 4 degrees C.
Mollic epipedon thickness - 18 to 40 cm and may include part of the Bk1 horizon
Soil surface - at least strongly effervescent when mixed to 18 cm
Depth to calcic horizon - 10 to 40 cm
Control section (weighted average) - more the 40 percent calcium carbonate by weight
Note: Some pedons may have an A2 or Bw horizon.
A horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 3 to 5 dry; 2 or 3 moist
Chroma: 1 to 3; dry or moist
Clay content: 15 to 27 percent
Rock fragments: 15 to 35 percent--15 to 30 percent gravel, 0 to 25 percent cobbles
Calcium carbonate equivalent: 3 to 15 percent
Reaction: pH 7.8 to 8.4
Bk1 horizon
Hue: 10YR or 2.5Y; dry or moist
Value: 4 to 6 dry; 2 to 4 moist
Chroma: 2 or 3; dry or moist
Texture: loam or sandy loam
Clay content: 15 to 27 percent
Rock fragments: 25 to 60 percent--20 to 50 percent gravel, 0 to 15 percent cobbles and stones
Calcium Carbonate Equivalent: 15 to 40 percent, including coarse fragments less than 20 mm in size
Reaction: pH 7.9 to 8.4
Bk2, Bk3 horizons
Hue: 10YR or 2.5Y; dry or moist
Value: 6 to 8 dry; 4 to 6 moist
Chroma: 2 to 4; dry or moist
Texture: loam or sandy loam
Clay content: 15 to 27 percent
Rock fragments: 35 to 70 percent--30 to 65 percent gravel, 5 to 25 percent cobbles and stones
Calcium Carbonate Equivalent: 40 to 60 percent, including coarse fragments less than 20 mm in size
Reaction: pH 7.9 to 8.4
COMPETING SERIES:
Hardhart (WY) - are moderately deep to lithic contact.
Irrawaddy (CO) - are moderately deep to lithic contact.
Pahreah (UT) - are moderately deep to lithic contact.
GEOGRAPHIC SETTING:
Landform - alluvial fans, fan remnants, colluvial aprons, hills and mountain slopes
Elevation - 1890 to 2600 meters
Slope - 2 to 60 percent
Parent material - alluvium, slope alluvium or colluvium derived from limestone
Climate - long, cold winters; moist springs; warm summers
Mean annual precipitation - 355 to 560 mm
Mean annual air temperature - 1 to 4 degrees F.
Frost-free period - 50 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Nikat soils are used mainly for rangeland. The vegetation is mainly bluebunch wheatgrass, Idaho fescue, kingspike fescue, POA (species), prairie junegrass, mountain big sagebrush, threetip sagebrush, rubber rabbitbrush, and other miscellaneous forbs.
DISTRIBUTION AND EXTENT: Nikat soils are of small extent in southwestern Montana. MLRA - 43B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Horse Prairie-South Valley Area - Part of Beaverhead County, Montana, 2011; proposed in Beaverhead County, Montana, 2008.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 18 cm (mixed - A, part of the Bk1 horizon)
Calcic horizon - from 33 to 152 cm (Bk1, Bk2, Bk3 horizons)
Particle-size control section - from 25 to 100 cm (part of Bk1, Bk2, part of Bk3 horizons)
Nikat soils have a cryic temperature regime and an ustic moisture regime.
Taxonomic version: Tenth Edition, 2006
National Cooperative Soil Survey
U.S.A.