LOCATION RAWNJAY UTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Calcic Argixerolls
TYPICAL PEDON: Rawnjay extremely cobbly loam, on a northeast facing, concave to concave, 12 percent slope in Gambel oak at an elevation of 5,081 feet. (Colors are for dry soil unless otherwise noted.) The surface is covered by 20 percent gravel, 15 percent cobbles, and 5 percent stones of mixed origin and subangular in shape.
A--0 to 7 inches; dark grayish brown (10YR 4/2) extremely cobbly loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure parting to weak fine and very fine granular; slightly hard, very friable, slightly sticky and slightly plastic; many fine and very fine, few medium roots; many fine and very fine interstitial and tubular pores; 15 percent gravel, 25 percent cobbles, 10 percent stones; slightly alkaline (pH 7.5); clear smooth boundary. (6 to 22 inches thick)
Bt1--7 to 11 inches; grayish brown (10YR 5/2) very gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure parting to moderate fine and very fine subangular blocky; hard, firm, moderately sticky and moderately plastic; common fine and very fine, few medium roots; common fine and very fine tubular pores; few discontinuous faint clay films on ped faces; 35 percent gravel, 5 percent cobbles, 5 percent stones; slightly alkaline (pH 7.5); abrupt smooth boundary.
Bt2--11 to 18 inches; brown (10YR 5/3) very gravelly loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure parting to moderate fine and very fine subangular blocky; hard, friable, moderately sticky and moderately plastic; common very fine and fine, few medium roots; common very fine and fine tubular pores; common discontinuous distinct clay films on ped faces; 35 percent gravel, 5 percent cobbles, 5 percent stones; slightly alkaline (pH 7.5); gradual smooth boundary. (total thickness of Bt horizons - 11 to 30 inches thick)
Bk1--18 to 25 inches; light brownish gray (10YR 6/2) very gravelly loam, dark grayish brown (10YR 4/2) moist; moderate fine and medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few very fine, fine and medium roots; few very fine tubular pores; 35 percent gravel, 5 percent cobbles, 5 percent stones; strongly effervescent, (11 percent calcium carbonate equivalent), carbonates are disseminated and segregated in common fine and very fine irregularly shaped soft masses and veins and in less than 1 mm thick coatings on rock fragments; moderately alkaline (pH 8.4); gradual wavy boundary. (7 to 36 inches or more thick)
Bk2--25 to 35 inches; light brownish gray (10YR 6/2) extremely stony sandy loam, dark grayish brown (10YR 4/2) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few fine and medium roots; many very fine and fine interstitial pores; 45 percent gravel, 10 percent cobbles, 20 percent stones; strongly effervescent, (10 percent calcium carbonate equivalent), carbonates are disseminated and segregated in few very fine irregular shaped soft masses and in less than 1 mm thick coatings on rock fragments; moderately alkaline (pH 8.4); gradual wavy boundary.
Bk3--35 to 60 inches; light gray (10YR 7/2) extremely stony fine sandy loam, grayish brown (10YR 5/2) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few fine and medium roots; many very fine and fine interstitial pores; 45 percent gravel, 10 percent cobbles, 20 percent stones; violently effervescent, (40 percent calcium carbonate equivalent), carbonates are disseminated and segregated in many very fine and fine irregular shaped soft masses and in 1 to 3 mm thick coatings on rock fragments; strongly alkaline (pH 8.8).
TYPE LOCATION: Salt Lake County, Utah; about 1.2 miles northwest of Camp Williams; located about 200 feet west and 1,000 feet south of the northeast corner of sec. 27, T. 4 S., R. 1 W.; Jordan Narrows USGS quad; lat. 40 degrees 26 minutes 50 seconds N. and long. 111 degrees 56 minutes 48 seconds W., NAD 27
RANGE IN CHARACTERISTICS:
Soil moisture regime: Xeric moisture regime. Soil moisture control section is dry 45 to 60 consecutive days following the summer solstice.
Soil temperature regime: frigid
Mean annual soil temperature: 43 to 47 degrees F.
Surface rock fragments: 15 to 50 percent, subangular to angular in shape, dominantly cobbles and gravel of mixed origin.
Particle-size control section: 20 to 30 percent clay, 35 to 60 percent rock fragments, dominantly gravel and cobbles
Depth to secondary calcium carbonate: 12 to 30 inches
Thickness of the mollic epipedon: 10 to 20 inches, may include parts of the Bt horizons
A horizon:
Hue: 10YR
Value: 3 or 4 dry, 2 or 3 moist
Chroma: 1 to 3
Texture: loam
Rock fragments: 60 to 75 percent, dominantly cobbles and gravel, minor stones
Reaction: slightly alkaline
Bt horizon:
Hue: 10YR
Value: 4 or 5 dry, 3 or 4 moist
Chroma: 2 to 4
Texture: loam, clay loam, or sandy clay loam
Rock fragments: 35 to 60 percent, dominantly gravel and cobbles with minor stones
Reaction: slightly alkaline to moderately alkaline
Bk horizon:
Hue: 10YR
Value: 6 to 8 dry, 4 to 7 moist
Chroma: 2 or 3
Texture: fine sandy loam, sandy loam, loam
Rock fragments: 35 to 75 percent gravel, cobbles, or stones
Calcium carbonate equivalent (in calcic horizon): 5 to 15 percent in the upper part and 15 to 40 percent in the lower part
Reaction: moderately alkaline to strongly alkaline
COMPETING SERIES: These are the Amelar (NV), Broad (UT), Custco T (ID), Drage (ID), Remount (MT), Scalfar (NV), Searla (ID), Sheep Creek (UT), Small T (ID), Swampydraw T (ID) series.
Amelar, Custco, and Scalfar soils have xeric bordering on aridic moisture regimes.
Broad, Sheep Creek, and Small soils are moderately deep to bedrock.
Drage soils have less than 15 percent calcium carbonate equivalent in the Bk horizons and have xeric bordering on aridic moisture regimes.
Remount soils have 10 to 18 percent clay in the particle size control section and have less than 10 percent calcium carbonate equivalent in the Bk horizons.
Searla soils lack a calcic horizon.
Swampydraw soils have a mean annual soil temperature of 38 to 43 degrees F. and have xeric bordering on aridic moisture regimes.
GEOGRAPHIC SETTING: Rawnjay soils.
Parent material: lacustrine deposits, alluvium or colluvium derived from mixed sedimentary and igneous origins.
Landform: lake terraces, lake terrace escarpments, or stream terraces.
Slopes: 8 to 70 percent
Elevation: 4,500 to 5,200 feet
Mean annual air temperature: 41 to 45 degrees F.
Mean annual precipitation: 16 to 22 inches.
Wettest months: October to May.
Driest months: June to September.
Frost-free period: 70 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hillfield, Kidman, and Sterling series.
Hillfield and Kidman: are not skeletal, are on convex positions, and under mountain big sagebrush.
Sterling: does not have an argillic horizon, is on convex positions and is under Wyoming big sagebrush.
DRAINAGE AND PERMEABILITY: Well drained, medium and high runoff, moderate permeability.
USE AND VEGETATION: Wildlife habitat and rangeland. Some potential native plants are Gambel oak, bluebunch wheatgrass, mountain brome, mountain snowberry, and serviceberry. These soils have been correlated to Mountain Gravelly Loam (Oak) - 047AY410UT range sites in Utah.
DISTRIBUTION AND EXTENT: Northern Utah. LRR D, MLRA 28A. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona.
SERIES ESTABLISHED: Salt Lake county, Utah. 1999. The name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: from 0 to 11 inches (A and Bt1 horizons).
Argillic horizon: from 7 to 18 inches (Bt1 and Bt2 horizons).
Calcic horizon: from 35 to 60 inches (2Bk2 horizon).
Keys to Soil Taxonomy: Eighth Edition 1998.