LOCATION PONCHO UT

Established Series
Rev. LDS/CSW/JWB
03/2011

PONCHO SERIES

The Poncho series consists of very shallow and shallow, well drained soils that formed in slope alluvium over residuum derived from shale and sandstone. Poncho soils are on cuestas, shale hills and structural benches. Slopes range from 3 to 35 percent. Mean annual precipitation is about 18 cm and the mean annual temperature is about 11 degrees C.

TAXONOMIC CLASS: Loamy, mixed, active, calcareous, mesic, shallow Typic Torriorthents

TYPICAL PEDON: Poncho sandy clay loam, on an east-southeast facing, convex, 12 percent slope in rangeland at an elevation of 1,710 meters. (Colors are for dry soil unless otherwise noted.) When described on March 4, 1999 the soil was dry from 0 to 5 cm and moist below that depth. The surface is covered by about 15 percent calcareous shale channers.

A--0 to 5 cm; light reddish brown (5YR 6/3) sandy clay loam, reddish brown (5YR 4/4) moist; 22 percent clay; moderate medium platy structure; friable, slightly hard, slightly sticky, slightly plastic; few coarse and medium and common fine roots and very fine roots; common fine and very fine vesicular and tubular pores; 10 percent channers, 3 percent parachanners; strongly effervescent, carbonates are finely disseminated; moderately alkaline (pH 7.9); clear wavy boundary. (3 to 8 cm thick)

C1--5 to 15 cm; light reddish brown (5YR 6/4) sandy clay loam, reddish brown (5YR 5/4) moist; 23 percent clay; weak fine subangular blocky structure; very friable, slightly hard, slightly sticky, slightly plastic; few medium and coarse and common fine and very fine roots; many very fine tubular and interstitial pores; few very fine gypsum crystals; 2 percent channers, 5 percent parachanners; strongly effervescent, carbonates are finely disseminated; moderately alkaline (pH 8.0); clear smooth boundary.

C2--15 to 23 cm; light reddish brown (5YR 6/4) very parachannery loam, reddish brown (5YR 4/4) moist; 27 percent clay; moderate medium and thick platy structure; friable, slightly hard, moderately sticky, moderately plastic; few fine and common very fine roots; common fine and very fine tubular and interstitial pores; few very fine gypsum crystals; 5 percent channers, 35 percent parachanners; strongly effervescent, carbonates are finely disseminated; moderately alkaline (pH 8.4); abrupt smooth boundary.

Cr--23 to 48 cm; reddish brown (5YR 5/4) weathered shale bedrock; few fine and very fine roots top of horizon.

TYPE LOCATION: Emery County, Utah; about 22.5 kilometers (14 miles) southeast of Emery; located about 800 feet east and 2,050 feet south of the northwest corner of sec. 2, T. 24 S., R. 7 E.; Big Bend Draw USGS quad; lat. 38 degrees 45 minutes 18 seconds N. and long. 111 degrees 7 minutes 11 seconds W., NAD 83

RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is affected by precipitation that peaks from July to October and falls evenly throughout the remainder of the year; typic aridic moisture regime
Mean annual soil temperature: 10.0 to 12.8 degrees C
Depth to paralithic contact: 10 to 51 cm to weathered bedrock
Depth to gypsum accumulations, when present: 3 to 8 cm
Thickness of the ochric epipedon: 3 to 8 cm

Particle-size control section (weighted averages):
Clay content: 20 to 35 percent total clay; 18 to 31 percent noncarbonate clay
Fine sand and coarser sand content: 20 to 60 percent
Rock fragment content: 0 to 25 percent, dominantly channers, parachanners and gravel

A horizon:
Hue: 7.5YR to 2.5YR
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 4 to 6 dry or moist
Texture: fine sand, loamy fine sand, sandy clay loam, loam, channery loam
Clay content: 4 to 27 percent
Rock fragments: 0 to 35 percent total; 0 to 10 percent flagstones, 0 to 3 percent cobbles, 0 to 30 percent channers, 0 to 15 percent gravel
Pararock fragments: 0 to 5 percent parachanners
Calcium carbonate equivalent: 3 to 15 percent
EC (mmhos/cm): 0 to 4
Gypsum: 0 to 2 percent
SAR: 0 to 4
Reaction: slightly alkaline to strongly alkaline

C horizon:
Hue: 5YR or 2.5YR
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 4 to 6 dry or moist
Texture: fine sandy loam, sandy clay loam, clay loam, channery sandy clay loam, channery clay loam, very parachannery loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 60 percent total; 0 to 10 percent flagstones, 0 to 3 percent cobbles, 0 to 30 percent channers, 0 to 15 percent gravel
Pararock fragments: 0 to 50 percent parachanners
Calcium carbonate equivalent: 3 to 15 percent
EC (mmhos/cm): 0 to 8
Gypsum: 0 to 5 percent. Some pedons have visible pedogenic or geogenic gypsum accumulations as crystals, filaments or veins.
SAR: 0 to 5
Reaction: moderately alkaline or strongly alkaline

COMPETING SERIES: These are the Persayo and Shalet series. Persayo soils have hues yellower than 7.5YR. Shalet soils have a mean annual soil temperature of 12.2 to 15 degrees C. (54 to 59 degrees F) and the soil moisture control section is affected by peak periods of precipitation in the winter months.

GEOGRAPHIC SETTING:
Parent material: slope alluvium over residuum derived from calcareous shale and sandstone. The surface of some pedons is overlain by eolian sand.
Landform: cuestas, shale hills and structural benches
Slopes: 3 to 35 percent
Elevation: 1,219 to 1,890 meters
Mean annual temperature: 8.9 to 11.7 degrees C
Mean annual precipitation: 15 to 23 cm
Precipitation pattern: Peaks from July to October and falls evenly throughout the remainder of the year
Frost-free period: 130 to 160 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Moenkopie, Mussentuchit and Nakai series. The Moenkopie soils are shallow to a lithic contact, have less than 18 percent clay in the particle-size control section and are on hard sandstone beds. The Mussentuchit soils have a gypsic horizon and are on gypsiferous outcrops. The deep or very deep Nakai soils have a calcic horizon and are in swales influenced by eolian sands between hills under Indian ricegrass and fourwing saltbush.

DRAINAGE AND PERMEABILITY: well drained, medium to very high runoff, moderate permeability.

USE AND VEGETATION: Grazing and wildlife habitat. Native vegetation consists of shadscale, galleta, bud sagebrush, Indian ricegrass, ephedra, sand dropseed, Castlevalley saltbush, scarlet globemallow, bottlebrush squirreltail and blackbrush.

DISTRIBUTION AND EXTENT: Central and east central Utah; LRR D, MLRA 34B; small extent; about 3,960 hectares (9,800 acres) in Emery and Grand Counties, Utah.

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

SERIES ESTABLISHED: Emery County, Utah, Emery Area, Utah, 2011, Parts of Emery, Carbon, Grand and Sevier Counties soil survey area. Named for Poncho Wash near the type location.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Series control section: The zone from 0 to 48 cm, or 25 cm below the paralithic contact.
Particle-size control section: The zone from 0 to 23 cm. (A and C horizons)
Ochric epipedon: The zone from 0 to 5 cm. (A horizon)
Paralithic contact: The contact with weathered bedrock at 23 cm. (Cr horizon)

The assignment of the cation-exchange activity class is supported by lab sample user pedon id number 92UT015101B (pedon number 92P0787). This sample is located about 54 miles east of the type location.

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

ADDITIONAL DATA: NSSL surface sample, user pedon id 92UT015131A (pedon number 92P0982). This sample is located about 54 miles east of the type location.

National Cooperative Soil Survey
U.S.A.