LOCATION BUNKIN UT

Established Series
Rev. CSW/JWB
03/2011

BUNKIN SERIES

The Bunkin series consists of shallow and very shallow, well drained soils that formed in colluvium, eolian sands and/or slope alluvium over residuum weathered from sedimentary rock. Bunkin soils are on hills, ledges, mountain slopes, scarps and structural benches. Slopes range from 3 to 70 percent. Mean annual precipitation is about 356 cm and the mean annual temperature is about 8.1 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, calcareous, mesic Aridic Lithic Ustorthents

TYPICAL PEDON: Bunkin extremely bouldery fine sandy loam, on a northeast facing, convex, 30 percent slope in rangeland at an elevation of 2,023 meters. (Colors are for dry soil unless otherwise noted.) The surface is covered by 30 percent boulders, 5 percent stones, 5 percent cobbles and 30 percent gravel.

A--0 to 7 cm; light brown (7.5YR 6/3) extremely bouldery fine sandy loam, brown (7.5YR 4/3), moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; few coarse and medium and common fine and very fine roots; many very fine interstitial pores; 30 percent boulders, 5 percent stones, 5 percent cobbles, 30 percent gravel; strongly effervescent (10 percent calcium carbonate equivalent); moderately alkaline (pH 7.9); clear wavy boundary.

C--7 to 20 cm; light brown (7.5YR 6/4) very gravelly fine sandy loam, brown (7.5YR 5/4), moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few coarse and medium and common fine and very fine roots; common fine and very fine tubular pores; 3 percent boulders, 3 percent stones, 2 percent cobbles, 30 percent gravel; strongly effervescent (12 percent calcium carbonate equivalent); moderately alkaline (pH 8.2); abrupt wavy boundary.

R--20 to 30 cm; conglomerate bedrock.

TYPE LOCATION: Emery County, Utah; about 4 kilometers (2.5 miles) northwest of Bob Hill Knoll on Cedar Mountain; located adjacent to the NW corner of sec. 25, T. 18 S., R. 10 E.; Bob Hill Knoll USGS quad; lat. 39 degrees 14 minutes 9.01 seconds N. and long. 110 degrees 44 minutes 21.23 seconds W., NAD 83

RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is usually moist in some part during the summer and early fall, and intermittently dry in the late fall. Ustic moisture regime bordering on aridic.

Mean annual soil temperature: 8 to 10.5 degrees C
Depth to lithic contact: 10 to 51 cm to bedrock, lithic

Particle-size control section (weighted averages):
Clay content: 15 to 27 percent
Rock fragment content: 35 to 75 percent

A horizon:
Hue: 2.5Y, 10YR or 7.5YR
Value: 5 or 6 dry; 4 to 6 moist
Chroma: 2 to 4 dry or moist
Texture: extremely bouldery fine sandy loam, very channery fine sandy loam, very stony loam, very gravelly fine sandy loam
Clay content: 15 to 25 percent
Carbonate clay content: 0 to 2 percent
Rock fragments: 35 to 80 percent total; 0 to 40 percent boulders, 0 to 25 percent stones, 0 to 20 percent cobbles, 0 to 60 percent channers or gravel
Calcium carbonate equivalent: 1 to 15 percent
EC (mmhos/cm): 0 to 4
SAR: 0 to 2
Reaction: pH 7.4 to 8.8

Bw horizon, where present, is less than 13 cm thick:
Hue: 10YR or 7.5YR
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 3 or 4 dry or moist
Texture: gravelly loam, very stony loam
Clay content: 15 to 27 percent
Carbonate clay content: 0 to 3 percent
Rock fragments: 15 to 60 percent total; 0 to 10 percent boulders, 0 to 25 percent stones, 0 to 20 percent cobbles, 0 to 35 percent channers or gravel
Calcium carbonate equivalent: 1 to 14 percent
EC (mmhos/cm): 0 to 4
SAR: 0 to 4
Reaction: pH 7.9 to 8.8

C horizon:
Hue: 10YR or 7.5YR
Value: 5 to 7 dry; 4 to 6 moist
Chroma: 3 or 4 dry or moist
Texture: very gravelly loam, very gravelly fine sandy loam, channery fine sandy loam, channery loam, very channery loam, very channery fine sandy loam
Clay content: 15 to 27 percent
Carbonate clay content: 0 to 4 percent
Rock fragments: 25 to 60 percent total; 0 to 10 percent boulders, flagstones and/or stones, 0 to 15 percent cobbles, 0 to 60 percent channers or gravel, 0 to 25 percent parachanners
Calcium carbonate equivalent: 3 to 15 percent
Gypsum content: 0 to 2 percent
EC (mmhos/cm): 0 to 8
SAR: 0 to 4
Reaction: pH 7.4 to 8.8

COMPETING SERIES: These are the Kydestea (AZ) and Metuck (AZ) series.
Kydestea soils: have mean annual soil temperature higher than 10.5 degrees C. (51 degress F.).
Metuck soils: have greater than 15 percent calcium carbonate equivalent throughout.

GEOGRAPHIC SETTING:
Parent material: colluvium, eolian sands and/or slope alluvium over residuum weathered from sedimentary rock, principally from Cretaceous sedimentary rock
Landform: hills, ledges, mountain slopes, scarps and structural benches
Slopes: 3 to 70 percent
Elevation: 1,524 to 2,377 meters
Mean annual temperature: 7.2 to 8.9 degrees C
Mean annual precipitation: 305 to 406 cm
Precipitation pattern: Wettest months are July to October and driest months are December and June
Frost-free period: 110 to 135 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gerst, Pollow, Stephouse, and Zigzag series. Gerst soils have a loamy particle-size control section and a shallow paralithic contact. Stephouse soils have a calcic horizon and are shallow. Pollow soils have an argillic horizon and a calcic horizon and are moderately deep under ponderosa pine on concave north aspects. The Zigzag soils have a clayey particle-size control section and are shallow to a paralithic contact with shale.

DRAINAGE AND PERMEABILITY: Well drained, high or very high runoff, moderate or moderately rapid permeability; high or moderately high saturated hydraulic conductivity.

USE AND VEGETATION: Grazing and wildlife habitat. Native vegetation consists of alderleaf mountain mahogany, twoneedle pinyon, Utah juniper, Stansbury cliffrose, Indian ricegrass, bluebunch wheatgrass, and Salina wildrye. In Utah these soils are correlated to Upland ecological sites.

DISTRIBUTION AND EXTENT: Central Utah, Warm Central Desertic Basins and Plateaus; LRR D, MLRA 34B; small extent; about 3,200 hectares (7,900 acres) in Carbon, Emery and Sevier Counties, Utah.

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

SERIES ESTABLISHED: Sevier County, Utah, Emery Area, Utah, 2011. Parts of Emery, Carbon, Grand, and Sevier soil survey area. The name is coined. Prior to 2010 Bunkin soils were included in the Colskel series.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Series control section: The zone from 0 to 20 cm.
Particle-size control section: The zone from 0 to 20 cm. (A and C horizons)
Ochric epipedon: The zone from 0 to 7 cm. (A horizon)
Lithic contact: The contact with conglomerate at 20 cm. (R horizon)

The assignment of the cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.

Taxonomic Version: Classified according to Keys to Soil Taxonomy, Eleventh Edition, 2010.

National Cooperative Soil Survey
U.S.A.