LOCATION IOKA UTEstablished Series
TAXONOMIC CLASS: Sandy-skeletal, mixed, mesic Typic Torriorthents
TYPICAL PEDON: Ioka very gravelly sandy loam, on a northwest facing, convex-concave, 5 percent slope in shadscale rangeland at an elevation of 5,300 feet. (Colors are for dry soil unless otherwise noted.)
The surface is covered by 65 percent subangular gravel and 10 percent subrounded cobbles. The fragments are predominantly hard sandstone or quartzite.
A--0 to 4 inches; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 5/3) moist; weak medium platy structure parting to weak very fine subangular blocky; hard, firm, moderately sticky and moderately plastic; few medium, fine, and very fine roots; few fine, common very fine tubular pores; 15 percent gravel, 5 percent cobbles; slightly effervescent, carbonates are disseminated; strongly alkaline (pH 8.6); clear smooth boundary. (1 to 5 inches thick)
C1--4 to 17 inches; very pale brown (10YR 7/3) very gravelly loamy sand, brown (10YR 5/3) moist; weak fine and very fine subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common fine and very fine, few medium roots; few fine and very fine random tubular pores; 45 percent gravel; slightly effervescent, carbonates are disseminated; strongly alkaline (pH 8.7); gradual wavy boundary.
C2--17 to 41 inches; light yellowish brown (10YR 6/4) very gravelly sand, yellowish brown (10YR 5/4) moist; single grain; slightly hard, loose, nonsticky and nonplastic; few very fine roots; common fine and very fine irregular pores; 50 percent gravel, 5 percent cobbles; slightly effervescent, carbonates are disseminated; strongly alkaline (pH 9.0); diffused irregular boundary.
C3--41 to 60 inches; light yellowish brown (10YR 6/4) very gravelly sand, yellowish brown (10YR 5/4) moist; single grain; loose, nonsticky and nonplastic; few very fine roots; common very fine irregular pores; 50 percent gravel, 5 percent cobbles; slightly effervescent, carbonates are disseminated; strongly alkaline (pH 9.0).
TYPE LOCATION: Uintah County-Duchesne County line, Utah; about 1 mile northeast of Crow Knoll; located about 1,100 feet east and 900 feet south of the northwest corner of sec. 35, T.9S., R.17E., SLBM; Crow Knoll, Utah USGS quad; lat. 39 degrees 59 minutes 31 seconds N. and long. 109 degrees 58 minutes 43 seconds W., NAD 27
RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is affected by precipitation that falls evenly through the year with a slight increase in late summer and early fall. Typic Aridic moisture regime.
Mean annual soil temperature: 47 to 49 degrees F.
Surface rock fragments: 35 to 80 predominantly subangular gravel from sedimentary and metamorphic rocks.
Particle-size control section: 0 to 10 percent clay; 35 to 60 percent rock fragments from sedimentary and metamorphic rocks.
A horizon:
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3 or 4 dry or moist
Texture: very gravelly sandy loam or gravelly loam
Calcium carbonate equivalent: 1 to 15 percent
EC (mmhos/cm): 0 to 4
SAR: 0 to 13
Reaction: moderately alkaline or strongly alkaline
C horizon:
Value: 6 or 7 dry, 4 or 5 moist
Chroma: 3 or 4 dry or moist
Texture: very gravelly sand, gravelly sandy loam, or very gravelly loamy sand
Calcium carbonate equivalent: 1 to 15 percent
EC (mmhos/cm): 0 to 4
SAR: 0 to 13
Gypsum: 0 to 3 percent
COMPETING SERIES: These are the Bluewing (NV), Gynelle (NV), Inmo (NV), Itme (NV), Izamatch (NV), Izo (NV), Leo (NV), Nepalto (UT), Wardenot (NV), and Willwood (WY) series.
Bluewing,
Gynelle,
Inmo,
Izamatch,
Itme,
Izo,
Leo, Wardenot: have soil moisture control sections that are affected by xeric moisture patterns.
Nepalto: have hue redder than 10YR.
Willwood: have moisture control sections affected by peak periods of precipitation in the spring and early summer, and have basalt parent material.
GEOGRAPHIC SETTING:
Parent material: alluvium and slope alluvium derived from sedimentary and metamorphic rocks
Landform: alluvial flats, alluvial fans, and fan remnants
Slopes: 0 to 25 percent
Elevation: 5,000 to 5,900 feet
Mean annual air temperature: 45 to 47 degrees F.
Mean annual precipitation: 5 to 8 inches
Frost-free period: 110 to 125 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Boreham, Jenrid, and Kilroy series.
Boreham soils occur on fan remnants and have a calcic horizon.
Jenrid soils occur on alluvial flats and are coarse-loamy.
Kilroy soils occur on fan remnants and have a calcic horizon.
DRAINAGE AND PERMEABILITY: Excessively drained, very low to moderate runoff, moderately rapid and rapid permeability.
USE AND VEGETATION: The major uses are rangeland, wildlife habitat, and recreation. The potential native plant community is shadscale, Indian ricegrass, galleta, black greasewood, alkali sacaton, bud sagebrush, and winterfat. These soils have been correlated to Desert Loam (Shadscale) - 034XY106UT, and Alkali Flat (Black Greasewood) - 034XY006UT range sites in Utah.
DISTRIBUTION AND EXTENT: Northeastern Utah. LRR D, MLRA 34. 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 taken from a nearby geographic location.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: The zone from 10 to 40 inches. (C1 and C2 horizons)
Ochric epipedon: The zone from 0 to 4 inches. (A horizon)
The cation exchange activity class was inferred from laboratory data from similar soils in the Uintah Area Soil Survey.
The surface texture modifier was determined following the guidelines outlined in the Utah document, "Procedures for Distributing Rock Fragments on the Surface Layer into the Upper 6 inches of Soil and Subsequent Naming of Map Units, April 1979."
Taxonomic version: Eighth Edition, 1998.