LOCATION BRAZIEL MT
Established Series
Rev. ADI-BDD-EMM
07/2012
BRAZIEL SERIES
The Braziel series consists of very deep, well drained soils that formed in till or colluvium derived from fine grained extrusive igneous and sedimentary rocks. These soils are on till plains, hills, escarpments, moraines, stream terraces and mountains. Slopes are 2 to 60 percent. Mean annual precipitation is about 17 inches, and mean annual temperature is about 41 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Pachic Argiustolls
TYPICAL PEDON: Braziel gravelly loam, rangeland (colors are for dry soil unless noted otherwise).
A1--0 to 4 inches; dark grayish brown (10YR 4/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine, fine, and medium roots; many very fine tubular pores; 5 percent cobbles, 15 percent gravel; neutral (pH 7.0); clear smooth boundary.
A2--4 to 8 inches; dark grayish brown (10YR 4/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine, and medium roots; many very fine and common fine tubular pores; 5 percent cobbles, 15 percent gravel; neutral (pH 7.2); clear smooth boundary. (Combined thickness of the A horizons is 7 to 15 inches.)
Bt1--8 to 17 inches; dark grayish brown (10YR 4/2) very gravelly loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine, and common medium roots; many very fine discontinuous tubular pores; few faint clay films on faces of peds and lining pores; 5 percent cobbles, 30 percent gravel; neutral (pH 6.8); clear wavy boundary. (9 to 21 inches thick)
Bt2--17 to 23 inches; brown (10YR 5/3) very gravelly clay loam, dark yellowish brown (10YR 3/4) moist; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, fine, and common medium roots; many very fine and fine continuous tubular pores; common distinct clay films on faces of peds and lining pores; 5 percent cobbles, 35 percent gravel; neutral (pH 7.2); clear wavy boundary. (6 to 20 inches thick)
Bt3--23 to 43 inches; brown (10YR 5/3) very gravelly clay loam, brown (10YR 4/3) moist; weak coarse subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common very fine and fine continuous tubular pores; common distinct clay films on faces of peds and lining pores; 10 percent cobbles, 40 percent gravel; neutral (pH 7.2); clear smooth boundary. (0 to 25 inches thick)
BC--43 to 60 inches; pale brown (10YR 6/3) extremely gravelly loam, brown (10YR 4/3) moist; weak coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; few very fine and fine tubular continuous pores; 45 percent gravel, 10 percent cobbles, 10 percent stones; neutral (pH 7.2).
TYPE LOCATION: Granite County, Montana; 2,300 feet west and 300 feet south of the NE corner of Sec. 8, T. 10 N., R. 13 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 41 to 46 degrees F.
Moisture control section - between 4 and 12 inches.
Mollic epipedon thickness - 16 to 30 inches.
A horizons
Value: 3, 4, or 5 dry; 2 or 3 moist
Chroma: 2 or 3 dry; 1, 2, or 3 moist
Texture: loam, silt loam, or clay loam
Clay content: 10 to 35 percent
Rock fragments: 5 to 60 percent--5 to 25 percent gravel, 0 to 20 percent cobbles, 0 to 15 percent stones
Reaction: pH 6.2 to 7.3
Bt1 horizon
Value: 4 or 5 dry; 3 moist
Chroma: 2 or 3 dry; 2 or 3 moist
Texture: sandy clay loam, clay loam, loam
Clay content: 20 to 35 percent
Rock fragments: 35 to 60 percent--30 to 45 percent gravel, 5 to 15 percent cobbles, 0 to 15 percent stones
Reaction: pH 6.6 to 7.3
Bt2 and Bt3 horizons
Value: 4, 5, or 6 dry; 3 or 4 moist
Chroma: 3 or 4 dry; 2, 3, or 4 moist
Texture: clay loam, sandy clay loam, loam
Clay content: 20 to 35 percent
Rock fragments: 35 to 75 percent--25 to 40 percent gravel, 5 to 35 percent cobbles, 0 to 15 percent stones
Reaction: pH 6.6 to 7.3
BC horizon
Value: 5, 6 or 7 dry; 3, 4, 5, or 6 moist
Chroma: 3 or 4 dry; 2, 3, or 4 moist
Texture: sandy loam, sandy clay loam, loam, or clay loam
Clay content: 15 to 30 percent
Rock fragments: 35 to 70 percent--25 to 40 percent gravel, 5 to 35 percent cobbles, 0 to 15 percent stones
Effervescence: none to slightly
CaCo3 equivalent: 0 to 5 percent
Reaction: pH 6.6 to 7.8
BC horizon is absent in some pedons.
COMPETING SERIES:
Adellern (NM) - Has horizons of secondary carbonate accumulations.
Fessler (MT) - Has horizons of secondary carbonate accumulations.
Mapache (NM) - Receives more moisture in between July and September.
Pastorius (CO) - hue redder than 10YR in the subsurface horizons; has a frost-free period greater than 90 days.
Pastorpeak (AZ) - has horizons of secondary carbonate accumulations; has hues of 7.5YR and redder throughout.
Zillion (UT) - has a calcic horizon.
GEOGRAPHIC SETTING:
Landform - moraines; hills; escarpments, till plains; stream terraces; mountains.
Elevation - 3,600 to 7,700 feet.
Slope - 2 to 60 percent.
Parent material - till or colluvium derived from fine grained extrusive igneous and sedimentary rocks.
Climate - long, cold winters; moist springs; short, warm summers.
Mean annual precipitation - 15 to 19 inches.
Mean annual air temperature - 39 to 44 degrees F.
Frost-free period - 70 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.
USE AND VEGETATION: Braziel soils are used mainly for rangeland and as wildlife habitat. The potential native vegetation is rough fescue, bluebunch wheatgrass, Idaho fescue, Columbia needlegrass, prairie junegrass, and forbs.
DISTRIBUTION AND EXTENT: Braziel soils are moderatly extensive in Southwestern Montana. MLRAs 43B and 44B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Powell County, Montana, 1995. Series proposed in Granite County, Montana, 1991.
REMARKS: Soil interpretation records: MT1302, MT1303. Diagnostic features and horizons recognized in this pedon are:
Mollic epipedon - from the surface to 17 inches (A horizons, Bt1 horizon);
Argillic horizon - from 8 to 43 inches (Bt1, Bt2, Bt3 horizons);
Particle-size control section - from 8 to 28 inches (Bt1, Bt2, part of Bt3 horizon).
Braziel soils have a frigid temperature regime and an ustic moisture regime.
ADDITIONAL DATA: Laboratory sample S89MT-039-1249.
National Cooperative Soil Survey
U.S.A.