LOCATION LABRE MT

Established Series
Rev. JMS/JAL/EMM
09/2014

LABRE SERIES

The Labre series consists of very deep, well drained soils that have moderately rapid permeability and are formed in material derived from baked sandstone and shale. These soils are on fans remnants, foothills, and uplands. Slopes are 2 to 25 percent. Mean annual temperature is about 43 degrees F., and mean annual precipitation is about 17 inches.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Haplustolls

TYPICAL PEDON: Labre channery loam, on a 7 percent convex, north-facing slope in grassland. When described, the soil was dry throughout. (Colors are for dry soil unless otherwise noted.)

A--0 to 5 inches; reddish brown (5YR 4/3) channery loam, dark reddish brown (5YR 3/3) moist; weak fine granular structure; soft, friable, nonsticky and nonplastic; many fine and very fine roots; 15 percent hard thin flat sandstone and shale fragments; slightly alkaline (pH 7.4); clear smooth boundary. (5 to 8 inches thick)

Bw1--5 to 10 inches; reddish brown (5YR 4/3) channery loam, dark reddish brown (5YR 3/3) moist; weak medium prisms parting to moderate fine subangular blocky structure; soft, friable, slightly sticky and slightly plastic; many fine and very fine roots; many fine and very fine pores; 25 percent hard thin flat sandstone and shale fragments; slightly alkaline (pH 7.4); clear wavy boundary. (2 to 7 inches thick)

Bw2--10 to 17 inches; reddish brown (5YR 4/4) very channery loam, dark reddish brown (5YR 3/4) moist; weak fine and very fine subangular blocky structure; soft, friable, nonsticky and nonplastic; many fine and very fine roots; many fine and very fine pores; 50 percent hard thin flat sandstone and shale fragments that are undercoated with lime; slightly effervescent; slightly alkaline (pH 7.6); clear smooth boundary. (5 to 7 inches thick)

Bk1--17 to 31 inches; pink (5YR 7/3) extremely channery loam, yellowish brown (10YR 5/4) moist; massive; soft, friable, nonsticky and nonplastic; common fine and very fine roots; many fine and very fine pores; 60 percent hard thin flat sandstone and shale fragments that are coated with lime; strongly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (5 to 15 inches thick)

Bk2--31 to 48 inches; very pale brown (10YR 7/3) extremely channery loam, yellowish brown (10YR 5/4) moist; massive; soft, friable, nonsticky and non- plastic; common very fine roots; many very fine pores; 65 percent hard thin flat sandstone and shale fragments; fragments are partially coated with lime; strongly effervescent; moderately alkaline (pH 8.4); gradual smooth boundary. (5 to 20 inches thick)

BC--48 to 60 inches; light brown (7.5YR 6/4) extremely channery loam, brown (7.5YR 5/4) moist; massive; soft, friable, nonsticky and nonplastic; few very fine roots; common very fine pores; 70 percent hard thin flat sandstone and shale fragments; strongly effervescent; moderately alkaline (pH 8.2).

TYPE LOCATION: Rosebud County, Montana; 200 feet west and 1400 feet north of SE corner of sec. 12, T. 4 S., R. 41 E.

RANGE IN CHARACTERISTICS:

Soil temperature: 38 to 47 degrees F.
Mollic epipedon thickness: 7 to 15 inches
Rock fragments in control section: 35 to 75 percent that are mainly porcelanite
Depth to calcic horizon: 12 to 24 inches

A horizon:
Hue: 5YR, 7.5YR, or 10YR
Value: 4 or 5 dry
Value: 2 or 3 moist
Chroma: 2 or 3, moist or dry
Texture: loam
Clay content: 10 to 27 percent
Rock fragments: 10 to 35 percent total
Flagstones, thin flat: 0 to 5 percent
Channers, thin flat: 15 to 30 percent
Reaction: pH 6.6 to 7.8

Bw1 horizon:
Hue: 2.5YR, 7.5YR, or 10YR
Value: 4 or 5 dry; 3 moist
Chroma: 2 or 3, dry or moist
Texture: loam
Clay content: 10 to 27 percent
Rock fragments: 15 to 40 percent total
Flagstones, thin flat: 0 to 5 percent
Channers, thin flat: 15 to 35 percent
Reaction: pH 7.4 to 8.4

Bw2 horizon:
Hue: 2.5YR, 5YR, 7.5YR, or 10YR
Value: 6 dry; 3 moist
Chroma: 4, dry or moist
Texture: loam
Clay content: 10 to 27 percent
Rock fragments: 35 to 55 percent total porcelanite
Flagstones, thin flat: 0 to 5 percent
Channers, thin flat: 35 to 50 percent
Reaction: pH 7.4 to 8.4

Bk horizons:
Hue: 5YR, 7.5YR, or 10YR
Value: 5, 6, or 7 dry; 4, 5, or 6 moist
Chroma: 2, 3, or 4; dry or moist
Texture: loam or fine sandy loam
Clay content: 8 to 27 percent
Rock fragments: 50 to 75 percent total porcelanite
Flagstones, thin flat: 0 to 20 percent
Channers, thin flat: 50 to 55 percent
Calcium carbonate equivalent: 15 to 30 percent
Reaction: pH 7.4 to 8.4

BC horizon:
Hue: 5YR, 7.5YR, 10YR, or 2.5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2, 3, or 4; dry or moist
Texture: loam or fine sandy loam
Clay content: 5 to 27 percent
Rock fragments: 60 to 75 percent total porcelanite
Flagstones, thin flat: 0 to 20 percent
Channers, thin flat: 50 to 55 percent
Reaction: pH 7.9 to 8.4

COMPETING SERIES:
Aguja (NM) - are 20 to 40 inches deep to a paralithic contact
Finleypoint (MT) - does not have horizons of secondary calcium carbonate accumulation
Flott (MT) - have E and E/Bw horizons
Kutler (CO) - are 20 to 40 inches deep to a paralithic contact
Perma (MT) - do not have horizons of secondary calcium carbonate accumulation
Peso (NM) - have a lithic contact at 20 to 40 inches
Pesowyo (WY) - have a lithic contact at 20 to 40 inches
Renegade (UT) - has a paralithic contact at 40 to 60 inches
Sandia (NM) - has a lithic contact at 40 to 60 inches
Slimbutte (MT) - do not have porcenlanite fragments in the soil
Subwell (MT) - have a lithologic discontinuity at 10 to 20 inches
Towave (UT) - have an ABk horizon
Veatch (CO) - have a lithic contact at 20 to 40 inches
Vigilante (MT) - has a lithic contact at 40 to 60 inches
Walstead (MT) - do not have porcenlanite fragments in the soil
Wanagan (ND) - has a lithologic discontinuity at 14 to 28 inches
Wimper (MT) - do not have porcenlanite fragments in the soil

GEOGRAPHIC SETTING:
Landform - fan remnants, foothills, and uplands that have a plane or convex surface.
Elevations - 3,250 to 4,700 feet.
Slope - predominantly 2 to 8 percent, but ranges from 2 to 25 percent. Parent material - material derived from baked sandstone and shale.
Climate - cool and moist with long cold winters and moist springs and summers.
Mean annual temperature - 38 to 45 degrees F.
Mean annual precipitation - 15 to 20 inches.
Frost free season is 80 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bitton, Cabba, Doney, Lamedeer, Ringling, Shambo, and Twin Creek soils. Bitton soils formed in alluvium on fans, foot slopes, and terraces, and typically have very gravelly loam profiles. Cabba soils are on uplands and have a paralithic contact at depths of 25 to 51 cm. Doney soils are on uplands and are moderately deep to a paralithic contact. Lamedeer soils are on fans, foot slopes, and uplands. They have an O horizon and do not have a mollic epipedon. Ringling soils are on uplands and have fractured bedrock at depths of 13 to 51 cm. Shambo soils are on fans and terraces and have solums with hue of 10YR or 2.5Y. Twin Creek soils are on fans, terraces, and foot slopes and contain less than 5 percent coarse fragments.

DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability.

USE AND VEGETATION: The Labre soils are used mainly for rangeland and to a lesser degree for cropland, hay, and pasture. The potential native vegetation is bluebunch wheatgrass, big bluestem, needleandthread, little bluestem, Idaho fescue, forbs, and shrubs.

DISTRIBUTION AND EXTENT: Eastern and central Montana. Labre soils are of small extent in southwestern Montana. MLRA 43B, 44B, 58A.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Fergus County, Montana, 1979.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the surface to 10 inches (A and Bw1 horizons)
Cambic horizon - the zone from 10 to 17 inches (Bw2 horizon)
Calcic horizon - the zone from 17 to 48 inches (Bk horizon)
Particle size control section - the zone from 10 to 40 inches (Bw2, Bk1 and Bk2 horizons)

Labre soils have a frigid temperature regime and an ustic moisture regime.

National Cooperative Soil Survey
U.S.A.