LOCATION SNAKEJOHN UTEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Typic Argiustolls
TYPICAL PEDON: Snakejohn loam, on a northwest facing, convex-concave, 4 percent slope in birchleaf mountainmahogany and Utah serviceberry browse at an elevation of 8,320 feet. (Colors are for dry soil unless otherwise noted.)
A--0 to 2 inches; brown (7.5YR 4/2) loam, very dark brown (7.5YR 2/2) moist; moderate very fine granular structure; soft, friable, slightly sticky and slightly plastic; many very fine and fine, common medium, few coarse roots; many very fine, common fine tubular pores; 10 percent gravel; neutral (pH 7.2); abrupt smooth boundary.
AB--2 to 5 inches; brown (7.5YR 4/3) clay loam, dark brown (7.5YR 3/2) moist; moderate fine and medium subangular blocky structure; hard, firm, sticky and plastic; many very fine and fine, common medium, few coarse roots; common very fine and fine, few medium tubular pores; 10 percent gravel; slightly alkaline (pH 7.6); clear smooth boundary. (combined thickness of A horizons is 3 to 6 inches)
Bt1--5 to 10 inches; brown (7.5YR 5/3) clay loam, dark brown (7.5YR 3/2) moist; moderate medium prismatic structure parting to moderate very fine and fine subangular blocky; hard, firm, sticky and plastic; common very fine and fine, few medium and coarse roots; common very fine and fine, few medium tubular pores; common discontinuous distinct clay films on faces of peds; 10 percent gravel; slightly alkaline (pH 7.8); clear smooth boundary.
Bt2--10 to 15 inches; brown (7.5YR 5/3) gravelly clay loam, dark brown (7.5YR 3/2) moist; moderate medium prismatic structure parting to moderate very fine and fine subangular blocky; hard, firm, sticky and plastic; common very fine and fine, few medium and coarse tubular pores; common continuous distinct clay films on faces of peds; 20 percent gravel; slightly alkaline (pH 7.8); abrupt wavy boundary. (combined thickness of Bt horizons ranges from 9 to 15 inches thick)
Bk1--15 to 32 inches; pale brown (10YR 6/3) gravelly clay loam, brown (10YR 4/3) moist; moderate medium prismatic structure parting to moderate very fine and fine subangular blocky; slightly hard, firm, sticky and plastic; common very fine and fine, few medium roots; common very fine and fine, few medium and coarse tubular pores; 15 percent gravel, 15 percent channers; strongly effervescent (33 percent calcium carbonate equivalent), carbonates are disseminated and segregated as common fine rounded masses and nodules; moderately alkaline (pH 8.4); abrupt irregular boundary. (13 to 19 inches thick)
Bk2--32 to 41 inches; very pale brown (10YR 8/2) very gravelly loam, very pale brown (10YR 7/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and fine, few medium tubular pores; 25 percent gravel, 25 percent channers; violently effervescent (55 percent calcium carbonate equivalent), carbonates are disseminated and segregated as many fine and medium masses; strongly alkaline (pH 8.8); clear wavy boundary. (13 to 25 inches thick)
R--41 inches; unweathered sandstone bedrock
TYPE LOCATION: Uintah County, Utah; about 31 miles south southeast of Bonanza, Utah; .5 miles northwest of Lone Spring; located about 1,500 feet east and 1,600 feet north of the southwest corner of sec. 18, T.14S., R.26E., SLBM; Rat Hole Ridge, Utah USGS quad; lat. 39 degrees 35 minutes 49 seconds N. and long. 109 degrees 3 minutes 5 seconds W., NAD 27.
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is affected by precipitation evenly distributed throughout the year with a slight increase in late summer and early fall. Typic Ustic moisture regime.
Mean annual soil temperature: 42 to 45 degrees F.
Depth to lithic contact: 40 to 60 inches to sandstone bedrock
Depth to calcic horizon: 15 to 30 inches
Thickness of the mollic epipedon: 7 to 15 inches
Particle-size control section: 27 to 35 percent clay; 10 to 35 percent rock fragments (predominantly gravel from shale and sandstone)
A and AB horizon:
Hue: 7.5YR or 10YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 or 3
Texture: loam and clay loam
Reaction: neutral or slightly alkaline
Bt and A/Bt (when present) horizon:
Hue: 7.5YR or 10YR
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 2 or 3
Texture: clay loam or gravelly clay loam
Rock fragments: 10 to 35 percent (predominantly gravel)
Reaction: neutral or slightly alkaline
Bk horizon:
Value: 4 or 5 moist, 6 to 8 dry
Chroma: 2 or 3
Rock fragments: 35 to 60 percent gravel and channers
Calcium carbonate equivalent: 15 to 55 percent
Reaction: moderately alkaline or strongly alkaline
COMPETING SERIES: Current and potential competitors are the Absarook, Beartooth, Beeno, Bielenberg, Bookcliff, Bullflat, Burtoner, Clancy, Clasoil, Dooley, Empedrado, Fairfield, Farnuf, Felor, Greenway, Gurney, Hangdo, Hoppers, Hyalite, Jeffcity, Kokoruda, Lininger, Livona, Martinsdale, Maudlin, Meagher, Moen, Pianohill, Placerton, Reeder, Reedwest, Sponseller, Trag, Tragmon, Trazuni, Tschicoma, Ulrant, Vida, Watne, Watrous, Williams, and Yegen series.
Absarook, Burtoner, Gurney, Maudlin, Moen, Pianohill, and Watrous: have a lithic contact at depths of 20 to 40 inches.
Beartooth, Bielenberg, Bullflat, Clasoil, Dooley, Empedrado, Fairfield, Farnuf, Felor, Greenway, Hangdo, Hyalite, Kokorudu, Livona, Martinsdale, Meagher, Trag, Tragmon, Trazuni, Vida, Watne, Williams, and Yegan: do not have bedrock within a depth of 60 inches.
Beeno, Clancy, Hoppers, Jeffcity, Lininger, Placerton, Reeder, and Reedwest: have a paralithic contact at depths of 20 to 40 inches.
Bookcliff: does not have a calcic horizon.
Sponsellor: have pyroclastic and basalt parent material and includes hue redder than 7.5YR.
Tschicoma: is noncalcareous to a depth of 40 inches or more and have clay minerals of volcanic origin.
Ulrant: have granitic rock fragments.
GEOGRAPHIC SETTING:
Parent material: loamy slope alluvium derived from shale and sandstone
Landform: hillslopes
Slopes: 3 to 15 percent
Elevation: 7,800 to 8,500 feet
Mean annual air temperature: 40 to 43 degrees F.
Mean annual precipitation: 16 to 22 inches
Frost-free period: 70 to 90 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gompers, Moonset, Utso, Whetrock series.
Gompers and Moonset soils occur on hillslopes and are shallow to shale bedrock.
Utso soils occur on hillslopes and have no argillic horizon.
Whetrock soils occur on hillslopes and are moderately deep to weathered shale.
DRAINAGE AND PERMEABILITY: Well drained, medium runoff, moderately slow permeability.
USE AND VEGETATION: The major uses are rangeland, wildlife habitat, and recreation. The potential native plant community consists of birchleaf mountainmahogany, Utah serviceberry, mountain big sagebrush, bluegrass, snowberry, elk sedge, and Gambel's oak. This soil has been correlated to Mountain Stony Loam (Browse) - 048AY451UT range site in Utah.
DISTRIBUTION AND EXTENT: Northeastern Utah. LRR E, MLRA 48A. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Uintah County, Uintah Area Soil Survey, Utah. 1998. The name is taken from a nearby geographic location.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: The zone from 5 to 16 inches. (Bt1 and Bt2 horizons)
Mollic epipedon: The zone from 0 to 15 inches. (A, A/Bt, Bt1, Bt2 horizons)
Argillic horizon: The zone from 5 to 16 inches. (Bt1, Bt2 horizons)
Calcic horizon: The zone from 16 to 41 inches. (Bk1, Bk2 horizons)
Classification changed from Typic Argiborolls to frigid Typic Argiustolls 12/98.
Taxonomic version: Eighth Edition, 1998.
The assignment of the superactive cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.