LOCATION MONTWEL UT+CO
Established Series
REV: GWL/RLM/SJJ
06/2014
MONTWEL SERIES
The Montwel series consists of moderately deep to shale , well drained, moderately slowly permeable soils that formed in slope alluvium and colluvium over residuum from variegated shale, siltstone, and sandstone. These soils are on hillslopes . Slopes are 2 to 90 percent. The average annual precipitation is about 8 inches and mean annual temperature is about 46 degrees F.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, mesic Typic Torriorthents
TYPICAL PEDON: Montwel clay loam, on an northeast facing 42 percent slope under Mormon-tea, shadscale, galleta, and snakeweed -rangeland at an elevation of 5,350 feet. (Colors are for air-dry soil unless otherwise noted)
A--0 to 2 inches; brown (7.5YR 5/4) clay loam, strong brown (7.5YR 4/6) moist; weak very fine, fine, and medium subangular blocky structure; soft, friable, moderately sticky and moderately plastic; few fine and very fine roots; few fine and common very fine tubular pores; slightly effervescent, (10 percent calcium carbonate equivalent), carbonates are disseminated; moderately alkaline (pH 8.4); abrupt smooth boundary. (2 to 4 inches thick)
C1--2 to 9 inches; pale brown (10YR 6/3) clay loam, yellowish brown (10YR 5/4) moist; massive; soft, friable, slightly sticky and slightly plastic; few fine and very fine roots; few fine and very fine tubular pores; few fine geogenic gypsum crystals; slightly effervescent, (3 percent calcium carbonate equivalent), carbonates are disseminated; moderately alkaline (pH 8.2); abrupt smooth boundary. (3 to 13 inches thick).
C2--9 to 24 inches; reddish brown (5YR 5/4) clay loam, reddish brown (5YR 4/4) moist; massive; slightly hard, firm, moderately sticky and moderately plastic; common fine and very fine roots; few very fine tubular pores; few fine geogenic gypsum crystals; very slightly effervescent, (6 percent calcium carbonate equivalent), carbonates are disseminated; moderately alkaline (pH 8.2); abrupt smooth boundary. (5 to 19 inches thick)
C3--24 to 36 inches; pinkish gray (7.5YR 7/2) silty clay loam, brown (7.5YR 5/4) moist; massive; hard, firm, slightly sticky and slightly plastic; few fine geogenic gypsum crystals; slightly effervescent, (5 percent calcium carbonate equivalent), carbonates are disseminated; moderately alkaline (pH 8.4); abrupt smooth boundary. (5 to 15 inches thick).
Cr--36 inches; fractured shale.
TYPE LOCATION: Uintah County, Utah; about 10 miles south of Jensen near Red Wash; 1,700 feet south and 1,800 feet east of the northwest corner of sec. 11, T. 7 S., R. 23 E., SLBM; USGS Red Wash, Utah quadrangle; 40 degrees , 13 minutes, 38 seconds north latitude, 109 degrees, 17 minutes, 47 seconds west longitude; NAD 27.
RANGE IN CHARACTERISTICS:
The soil moisture control section is affected by precipitation that falls evenly through the year, with a slight increase in the late summer and fall. This soil crosses precipitation zones that are considered to be Typic Aridic and Ustic Aridic. However, drier aspects and steep slopes offset the additional moisture in the Ustic Aridic zone. The soil moisture regime is typic aridic.
Mean annual soil temperature: 47 to 51 degrees F.
Depth to paralithic contact: 20 to 40 inches to shale
The surface is covered with 0 to 60 percent gravel and cobbles.
Calcium carbonate equivalent: 5 to 15 percent.
Particle-size control section: 27 to 35 percent clay, 15 to 35 percent fine sand or coarser, and 0 to 15 percent parachanners
A horizon:
Hue: 2.5YR through 7.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 through 6
Texture: clay loam or cobbly clay loam
Rock fragments: 0 to 25 percent gravel and cobbles
Reaction: moderately alkaline or strongly alkaline
C horizon:
The C horizon is horizontal beds of variegated, stratified weathered shale, siltstone and fine grained sandstone that slakes in water.
Hue: dominantly 2.5YR through 7.5YR with thin layers of 10YR, 2.5Y, or 5Y
Value: 4 through 7 dry, 4 or 5 moist
Chroma: 2 through 6
Texture: clay loam, or silty clay loam
Reaction: moderately alkaline or strongly alkaline
Geogenic Gypsum: 1 to 10 percent
COMPETING SERIES: These are the
Gotho,
Greybull,
Hostage (T),
Norland (T),
Ohtog,
Teapo, and
Turzo series.
Gotho,
Hostage,
Norland,
Ohtog and
Turzo soils lack a paralithic contact within 40 inches of the surface.
Greybull soils have soil moisture control sections that are influenced by half the yearly precipitation falling during the months of April through June. Greybull soils also have lithochromic hues that are dominantly more yellow than 7.5YR.
Teapo soils have more than 35 percent fine sand or coarser and have hue more yellow than 7.5YR.
GEOGRAPHIC SETTING:
Parent material: slope alluvium and colluvium over residuum derived from variegated shale, interbedded with sandstone and siltstone
Landform: hillslopes
Slope: 2 to 90 percent
Elevation: 4,600 to 6,400 feet
Mean annual temperature: 45 to 49 degrees F
Mean annual precipitation: 5 to 12 inches
Freeze-free period: 110 to 140 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Clapper,
Denco,
Hideout, and
Milok soils.
Denco soils are on hillslopes and have a fine ,smectitic particle size control section.
Clapper and
Milok soils are on fan remnants and have a calcic horizon.
Hideout soils are on hillslopes and have a lithic contact within 20 inches of the surface.
DRAINAGE AND PERMEABILITY: Well drained, low to high runoff; moderately slowly permeable.
USE AND VEGETATION: These soils are used mainly for rangeland, wildlife habitat, and recreation. Potential vegetation is shadscale, bud sagebrush, galleta, and Indian ricegrass. This soil has been correlated to the Desert - Very Steep Shallow Loam (Shadscale) - 034XY133UT range site at the type location in Utah.
DISTRIBUTION AND EXTENT: Northeastern Utah. The series is of moderate extent. LLR D. MLRA 34.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Duchesne County, Utah, 1948.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: The zone from 10 to 36 inches. (C2 and C3 horizons)
Ochric epipedon: The zone from the surface to a depth of 2 inches. ( A horizon)
Gypsum: Geogenic gypsum is present in the zone from 2 to 36 inches. (C1, C2, and C3 horizons)
Paralithic contact: The contact with shale at 36 inches. (Cr horizon)
These soils are located in an area that ranges up to 12 inches of precipitation , which is typically an Ustic Aridic zone in Utah. However, the interaction of physical conditions (i.e., dry aspects and steep slopes) and moisture, only allow desert plant communities to predominate. Thus, the soil moisture regime is more reflective of Typic Aridic.
Type location moved to Uintah County because of vague original location description.
The type location profile description was reviewed, updated, and revised to meet current standards on 2/1999. Horizon designations were modified in 2014 to remove the "y" suffix from C horizons, because the gypsum is described as being geogenic, or inherent in the parent materials. This series should be re-evaluated in the future to confirm the gypsum is dominantly geogenic, and not secondary pedogenic accumulations.
Taxonomic version: Eighth Edition, 1998.
National Cooperative Soil Survey
U.S.A.