LOCATION MAXVILLE MT+IDEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive Ustic Haplocryolls
TYPICAL PEDON: Maxville gravelly loam, native grassland (colors are for dry soil unless otherwise noted).
A--0 to 11 inches; dark grayish brown (10YR 4/2) gravelly loam, very dark grayish brown 910YR 3/2) moist; moderate medium and fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many fine and very fine roots and common medium roots; 15 percent pebbles; neutral (pH 6.9); clear wavy boundary. (5 to 13 inches thick)
Bw--11 to 19 inches; grayish brown (10YR 5/2) loam, dark grayish brown (10YR 4/2) moist; weak medium prismatic structure parting to weak medium subangular blocky; soft, very friable, slightly sticky and slightly plastic; many fine and very fine roots and common medium roots; 10 percent pebbles; neutral (pH 7.2); abrupt wavy boundary. (6 to 10 inches thick)
Bk1--19 to 28 inches; pale brown (10YR 6/3) loam, brown (10YR 5/3) moist; massive; soft, very friable, slightly sticky and slightly plastic; common medium, fine, and very fine roots; 10 percent pebbles; lime coatings on pebbles; disseminated lime; violently effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (6 to 15 inches thick)
Bk2--28 to 34 inches; pale brown (10YR 6/3) gravelly loam, brown (10YR 5/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; common medium, fine, and very fine roots; 25 percent pebbles; lime coatings on pebbles; disseminated lime; violently effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary. (3 to 6 inches thick)
2C--34 to 60 inches; pale brown (10YR 6/3) very gravelly loamy sand, brown (10YR 5/3) moist; single grain; loose, nonsticky and nonplastic; few medium and fine roots; 50 percent pebbles, 5 percent cobbles; strongly effervescent; slightly alkaline (pH 7.5).
TYPE LOCATION: Madison County, Montana; approximately 1,900 feet east and 200 feet south of the NW corner of sec. 10, T. 12 S. R. 2 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 38 to 42 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 8 to 11 inches.
Rock fragments - 5 to 35 percent above the 2C horizon and 50 to 70 percent in the 2C horizon.
Depth to Bk horizon - 11 to 26 inches.
Depth to 2C horizon - 20 to 40 inches.
A horizon - Value: 4 or 5 dry; 2 or 3 moist
Clay content: 15 to 25 percent
Rock fragments: 5 to 30 percent--0 to 15 percent cobbles; 5 to 15 percent pebbles
Reaction: pH 6.6 to 7.3
Bw horizon - Value: 5 dry; 3 or 4 moist
Chroma: 2, 3, or 4
Texture: loam or clay loam
Clay content: 18 to 30 percent
Rock fragments: 5 to 30 percent--0 to 5 percent cobbles; 5 to 25 percent pebbles
Reaction: pH 6.6 to 7.3
Bk horizons - Hue: 10YR or 2.5Y
Value: 6 or 7 dry; 5 or 6 moist
Chroma: 2, 3, or 4
Texture: loam or clay loam
Clay content: 18 to 30 percent
Rock fragments: 10 to 35 percent--0 to 5 percent cobbles; 10 to 30 percent pebbles
Calcium Carbonate Equivalent: 5 to 15 percent
Reaction: pH 6.6 to 8.4
The lower part of the Bk horizon many have greater than 35 percent rock fragments in some pedons.
2C horizon - Hue: 10YR
Value: 6 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: loamy sand or sand
Clay content: 0 to 10 percent
Rock fragments: 50 to 70 percent--0 to 10 percent cobbles; 50 to 60 percent pebbles
Reaction: pH 6.6 to 8.4
COMPETING SERIES:
Manchego (CO) - does not have horizons of secondary carbonate accumulation.
GEOGRAPHIC SETTING:
Landform - alluvial fans and stream terraces.
Elevation - 6,000 to 7,500 feet.
Slope- 2 to 8 percent.
Parent material - eolian material and alluvium.
Climate - long, cold winters; cool, moist springs; warm summers.
Mean annual precipitation - 15 to 19 inches.
Mean annual temperature - 36 to 40 degrees F.
Frost-free period - 50 to 70 days.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability above the 2C horizon and rapid permeability in the 2C horizon.
USE AND VEGETATION: Maxville soils are used mainly for rangeland. Potential native vegetation is mainly basin wildrye, Richardson needlegrass, Columbia needlegrass, Idaho fescue, and big sagebrush. Bluebunch wheatgrass dominates in the lower end of the precipitation range.
DISTRIBUTION AND EXTENT: Maxville soils are of moderate extent in the cool intermountain valleys of southwestern Montana and eastern Idaho.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Madison County, Montana, 1983.
REMARKS: Soil Interpretations Records: MT0417 and MT0667. Diagnostic haorizons and features recognized in this pedon are: a mollic epipedon from the soil surface to 11 inches (A horizon); a cambic horizon from 11 to 19 inches (Bw horizon); horizons of secondary carbonate accumulation from 19 to 34 inches (Bk1 and Bk2 horizons); a lithologic discontinuity at 34 inches (2C horizon). Maxville soils have an ustic moisture regime and a cryic temperature regime.