LOCATION MOWBRAY MTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Haplustepts
TYPICAL PEDON: Mowbray very channery loam, coniferous forest (colors are for dry soil unless otherwise noted).
Oi--2 inches to 0; undecomposed and slightly decomposed forest litter.
A--0 to 2 inches; dark grayish brown (2.5Y 4/2) very channery loam, very dark grayish brown (2.5Y 3/2) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine interstitial pores and few very fine tubular pores; 25 percent channers, 10 percent flagstones, 5 percent cobbles; neutral (pH 6.6); abrupt smooth boundary. (2 to 7 inches thick)
Bw--2 to 11 inches; olive (5Y 5/3) very channery loam, olive (5Y 4/3) moist; moderate coarse subangular blocky structure parting to moderate fine granular; hard, very friable, slightly sticky and slightly plastic; many very fine, fine and medium roots, and few coarse roots; many very fine interstitial pores and common very fine tubular pores; 20 percent channers, 15 percent flagstones, 10 percent cobbles; neutral (pH 6.6); clear smooth boundary. (8 to 13 inches thick)
Bk--11 to 22 inches; olive (5Y 5/3) very flaggy loam, dark grayish brown (2.5Y 4/2) moist; weak fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine, fine, and few coarse roots; many very fine interstitial pores; 20 percent flagstones, 15 percent cobbles, 15 percent channers; 40 percent channer sized soft fragments; many distinct lime coatings on surfaces of flagstones, cobbles, and channers; disseminated lime; violently effervescent; slightly alkaline (pH 7.8); gradual wavy boundary. (8 to 46 inches thick)
BC--22 to 60 inches; grayish brown (2.5Y 5/2) very flaggy loam, dark grayish brown (2.5Y 4/2) moist; weak very thin platy structure; soft, very friable, slightly sticky and slightly plastic; few fine, medium and coarse roots; many fine interstitial pores; 25 percent flagstones, 10 percent cobbles, 20 percent channers; 20 percent channer size soft fragments; disseminated lime; strongly effervescent; moderately alkaline (pH 8.0).
TYPE LOCATION: Carter County, Montana; 1,400 feet east and 2,150 feet north of the SW corner of sec. 5, T. 3 S., R. 62 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 42 to 47 degrees F.
Moisture control section - between 8 and 24 inches.
Depth to Bk horizon - 10 to 20 inches.
A horizon - Hue: 10YR or 2.5YR
Value: 4, 5, or 6 dry; 2, 3, 4 or 5 moist
Chroma: 2 or 3
Clay content: 15 to 25 percent
Rock fragments: 15 to 60 percent--0 to 10 percent cobbles, 0 to 10 percent flagstones, 15 to 45 percent channers
Reaction: pH 6.6 to 7.8
Bw horizon - Hue: 10YR, 2.5Y, or 5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: loam or sandy loam
Clay content: 15 to 27 percent
Rock fragments: 30 to 60 percent--5 to 10 percent cobbles, 10 to 15 percent flagstones, 15 to 35 percent channers
Soft fragments: 0 to 20 percent
Effervescence: noneffervescent or slightly effervescent
Reaction: pH 6.6 to 7.8
Bk horizon - Hue: 10YR, 2.5Y, or 5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: loam or sandy loam
Clay content: 18 to 30 percent
Rock fragments: 40 to 80 percent--10 to 25 percent cobbles, 10 to 35 percent flagstones, 10 to 45 percent channers
Soft fragments: 10 to 40 percent
Calcium carbonate equivalent: 5 to 15 percent
Effervescence: strongly effervescent or violently effervescent
Reaction: pH 7.4 to 8.4
BC horizon, where present - Hue: 2.5Y or 5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2, 3, or 4
Texture: loam or clay loam
Clay content: 18 to 30 percent
Rock fragments: 35 to 60 percent--0 to 10 percent cobbles, 15 to 25 percent flagstones, 20 to 25 percent channers
Soft coarse fragments: 10 to 40 percent
Calcium carbonate equivalent: 0 to 15 percent
Effervescence: noneffervescent through strongly effervescent
Reaction: pH 7.4 to 8.4
COMPETING SERIES:
Kadygulch (MT) - does not have horizons of secondary carbonate accumulation.
Kingspoint (MT) - have albic horizons; do not have soft rock fragments.
Pathead (UT) - are moderately deep to sandstone.
Repkie (MT) - does not have horizons of secondary carbonate accumulation.
Repp (MT) - have albic horizons; do not have soft rock fragments.
Specie (CO) - have hue of 5YR or redder.
Wilde (MT) - are moderately deep to a lithic contact; does not have horizons of secondary carbonate accumulation.
Wildgen (MT) - have a horizon of lamellae; do not have carbonate accumulations above a depth of 40 inches.
Wilspring (MT) - are moderately deep to a lithic contact.
GEOGRAPHIC SETTING:
Landform - hills.
Elevation - 3,000 to 5,800 feet. It ranges to 6,000 feet in the foothills of the mountains.
Slope- 15 to 60 percent.
Parent material - colluvium.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 15 to 19 inches.
Mean annual temperature - 40 to 45 degrees F.
Frost-free period - 90 to 130 days. It ranges to 70 days in the foothills of the mountains.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Mowbray soils are used mainly for timber production and understory grazing. Potential native vegetation is mainly ponderosa pine with a sparse understory of bluebunch wheatgrass, green needlegrass, and common chokecherry.
DISTRIBUTION AND EXTENT: Mowbray soils are of small extent in the uplands of southeastern Montana and northwestern South Dakota.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Carter County, Montana, 1992.
REMARKS: Soil interpretations record: MT1140. Diagnostic horizons and features recognized in this pedon are: an ochric epipedon from the soil surface to 7 inches (A and B horizons); a cambic horizon from 2 to 11 inches (Bw horizon); an accumulation of secondary calcium carbonates from 11 to 22 inches (Bk horizon); a particle-size control section from 10 to 40 inches (Bk and BC horizons). Mowbray soils have a frigid temperature regime and an ustic moisture regime.