LOCATION TRAVONA MTEstablished Series
TAXONOMIC CLASS: Ashy, glassy, frigid Vitrandic Haplustolls
TYPICAL PEDON: Travona ashy loam, in rangeland (colors are for dry soil unless otherwise noted).
A--0 to 9 inches; grayish brown (10YR 5/2) ashy loam, very dark grayish brown (10YR 3/2) moist; moderate medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and medium roots; few medium and common fine tubular pores; 10 percent gravel; neutral (pH 6.6); clear wavy boundary. (7 to 10 inches thick)
Bw--9 to 23 inches; grayish brown (10YR 5/2) ashy loam, dark grayish brown (10YR 4/2) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and medium roots; few medium and common fine tubular pores; 10 percent gravel; neutral (pH 7.0); clear wavy boundary. (10 to 15 inches thick)
Bk--23 to 41 inches; very pale brown (10YR 8/2) ashy loam, pale brown (10YR 6/3) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and slightly plastic; common fine and few medium roots; common fine tubular pores; 10 percent gravel; common fine masses of lime; violently effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (10 to 20 inches thick)
BCk--41 to 60 inches; very pale brown (10YR 8/2) ashy sandy loam, pale brown (10YR 6/3) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and slightly plastic; few very fine and fine roots; common very fine and fine tubular pores; disseminated lime; few fine masses of lime; violently effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (10 to 20 inches thick)
TYPE LOCATION: TYPE LOCATION: Silver Bow County, Montana; UTM Zone 12: 376885e, 5099105n, NAD 83.
RANGE IN CHARACTERISTICS:
Soil Temperature - 41 to 46 degrees F.
Moisture control section - between 4 and 12 inches
Mollic epipedon thickness - 7 to 10 inches
A horizon - Value: 3, 4 or 5 dry; 2 or 3 moist
Chroma: 1 or 2
Clay content: 10 to 20 percent
Rock fragments: 5 to 15 percent gravel
Volcanic glass: 30 to 40 percent
AOE Al + 1/2 Fe: 0.10 to 0.25 percent
Bulk density: 1.1 to 1.3 g/cc
Reaction: 5.8 to 7.4
Bw horizon - Value: 6, 7 or 8 dry: 6 or 7 moist
Chroma: 2 or 3
Texture: sandy clay loam, loam or sandy loam
Clay content: 12 to 24 percent
Rock fragments: 5 to 17 percent; 5 to 15 percent gravel, 0 to 2 percent cobbles
Volcanic glass: 30 to 40 percent
AOE Al + 1/2 Fe: 0.10 to 0.25 percent
Bulk density: 1.2 to 1.4 g/cc
Reaction: 6.4 to 7.6
Bk horizon - Value: 6, 7 or 8 dry: 6 or 7 moist
Chroma: 2 or 3
Texture: loam, clay loam, or coarse sandy loam
Clay content: 12 to 20 percent
Rock fragments: 5 to 17 percent; 5 to 15 percent gravel; 0 to 2 percent cobbles
Volcanic glass: 30 to 40 percent
AOE Al + 1/2 Fe: 0.10 to 0.25 percent
Bulk density: 1.3 to1.5 g/cc
Calcium Carbonate Equivalent: 5 to 20 percent
Reaction: 7.8 to 8.4
BCk horizon - Value: 6, 7 or 8 dry: 6 or 7 moist
Chroma: 2 or 3
Texture: sandy loam, coarse sandy loam, or loamy coarse sand
Clay content: 6 to 18 percent
Rock fragments: 5 to 17 percent; 5 to 15 percent gravel; 0 to 2 percent cobbles
Volcanic glass: 30 to 40 percent
AOE Al + 1/2 Fe: 0.10 to 0.25 percent
Bulk density: 1.3 to1.5 g/cc
Calcium Carbonate Equivalent: 2 to 10 percent
Reaction: 7.8 to 8.4
COMPETING SERIES:
Elflint (MT) - moderately deep
Jarmills (NM) - does not have horizon of carbonate accumulation
GEOGRAPHIC SETTING:
Landform- alluvial fans and hills.
Elevation - 5,100 to 6,100 feet.
Slope - 1 to 12 percent.
Parent material - volcanic ash influenced alluvium.
Climate - long, cold winters; cool, moist springs; warm summers.
Mean annual precipitation - 12 to 16 inches.
Mean annual air temperature - 40 to 43 degrees F.
Frost-free period - 70 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the Chinasprings series. Chinasprings soils have argillic horizons.
DRAINAGE AND PERMEABILITY: Well drained, moderate permeability.
USE AND VEGETATION: Travona soils are primarily used for rangeland. Potential native vegetation is chiefly mixed grasses, such as bluebunch wheatgrass, rough fescue and Idaho fescue with some areas of widely scattered Douglas fir.
DISTRIBUTION AND EXTENT: Travona soils are of small extent in southwestern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Silver Bow County, Montana, 2007.
REMARKS: Diagnostic horizons and features recognized in this pedon are: a mollic epipedon from the surface to 9 inches (A horizon); a cambic horizon from 9 to 23 inches (Bw horizon); horizons of secondary carbonate accumulation from 23 to 60 inches (Bk and BCk horizons). Travona soils have a frigid temperature regime and an ustic moisture regime.