LOCATION VENTURE                 UT

Established Series
Rev: GBT/JTB/TWH
08/2011

VENTURE SERIES

The Venture series consists of shallow, well drained soils that formed in alluvium, colluvium, and residuum and weathered from basic and intermediate igneous rocks. Venture soils are on mountainsides and ridges and have slopes of 1 to 40 percent. The average annual precipitation is about 12 inches and the mean annual temperature is about 42 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid, shallow Petrocalcic Paleustolls

TYPICAL PEDON: Venture very cobbly silt loam--rangeland. (Colors are for air-dry soil unless otherwise stated.)

A--0 to 6 inches; dark grayish brown (10YR 4/2) very cobbly silt loam, very dark brown (10YR 2/2) moist; weak fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and medium roots; few fine and medium tubular pores; 30 percent cobbles, 25 percent gravel and 5 percent stones; neutral (pH 7.2); clear smooth boundary. (3 to 7 inches thick)

Bt--6 to 10 inches; brown (10YR 4/3) very gravelly clay loam, dark brown (10YR 3/3) moist; weak medium angular blocky structure; very hard, firm, moderately sticky and moderately plastic; few fine and medium roots; few fine tubular pores; few thin clay films; 30 percent gravel and 5 percent cobbles; neutral (pH 7.0); clear smooth boundary. (4 to 15 inches thick)

Btk--10 to 15 inches; pale brown (10YR 6/3) very gravelly clay loam, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky structure; hard, firm, slightly sticky and moderately plastic; common fine and medium and few coarse roots; few fine tubular pores; few thin clay films; 30 percent gravel and 5 percent cobbles; moderately calcareous; moderately alkaline (pH 8.4); gradual wavy boundary. (0 to 5 inches thick)

Bkm--15 inches; indurated lime-cemented hardpan.

TYPE LOCATION: Garfield County, Utah; about 18 miles north of Panguitch, about 8 miles north of Bear Valley Junction and U.S. Highway 89; 1,800 feet south and 900 feet west of northeast corner of sec. 34 T. 31 S., R. 5 W., SLBM; Fremont Pass USGS quad; lat. 38 degrees 04 minutes 46.3 seconds N. and long. 112 degrees 04 minutes 31.57 seconds W., NAD 83

RANGE IN CHARACTERISTICS:
Mean annual soil temperature immediately above the petrocalcic: 43 to 45 degrees F.
Mean summer soil temperature: 61 to 63 degrees F
Soil moisture: the soils are dry in parts of the moisture control section for 60 to 75 days during the winter, but are moist for 50 to 55 percent of the time when the soil temperature immediately above the petrocalcic is more than 41 degrees F. Ustic regime, aridic subclass.
Thickness of mollic epipedon: 8 to 13 inches
Depth to secondary carbonates: 9 to 13 inches
Depth to the petrocalcic horizon: 10 to 20 inches

Particle-size control section (weighted averages)
Rock fragment content: 35 to 45 percent

A horizon:
Hue: 10YR or 7.5YR
Value: 2 or 3 moist
Chroma: 2 or 3
Reaction: neutral or slightly alkaline.

Bt and Btk horizons:
Hue: 10YR or 7.5YR
Value: 4 to 6 dry, 3 or 4 moist
Chroma: 3 or 4 dry, 2 or 3 moist.
Texture: very cobbly clay loam or very gravelly clay loam.
Clay content: 27 to 35 percent
Rock fragment content: 35 to 60 percent, but average 35 to 40 percent, mostly gravel and cobbles
Reaction: Bt horizon-- neutral or slightly alkaline; Btk-- slightly alkaline or moderately alkaline.

Bk horizon (present in some pedons above the petrocalcic):
Hue: 10YR
Value: 6 or 7 dry, 4 or 5 moist
Chroma: 2 or 3, dry or moist
Texture: very gravelly loam or very cobbly loam
Rock fragment content: 35 to 50 percent, mostly gravel and cobbles
This horizon is strongly calcareous
Reaction: moderately alkaline to strongly alkaline
Thickness: 0 to 4 inches

COMPETING SERIES: There are no other series currently recognized in this family. A similar soil in a closely related family is the Circleville series. Circleville soils are moderately deep to bedrock and do not have a petrocalcic horizon.

GEOGRAPHIC SETTING: Venture soils are on mountainsides and ridges. (see Remarks) Slope is 1 to 40 percent. They formed in alluvium, colluvium, and residuum derived from basic and intermediate igneous rocks. Elevations are 6,500 to 7,800 feet. The climate is semiarid to dry subhumid with the average annual precipitation of 12 to 14 inches. The mean annual temperature is 40 to 45 degrees F. The mean summer temperature is 59 to 61 degrees F., and the freeze-free period is 70 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Comodore, Dalcan and Tolman soils. Comodore, Dalcan and Tolman soils do not have a petrocalcic horizon. Also, Comodore and Tolman soils are shallow over bedrock. Dalcan soils are moderately deep to bedrock.

DRAINAGE AND PERMEABILITY: Well drained, slow to medium runoff; moderately slow permeability.

USE AND VEGETATION: The soils are used for rangeland and wildlife habitat. At the type location the native vegetation is mainly black sagebrush, bluegrass, antelope bitterbrush, and Douglas rabbitbrush. In other areas, twoneedle pinyon and Utah juniper are included.

DISTRIBUTION AND EXTENT: South-central Utah, Western Garfield County. MLRA 47. The soils are not extensive.

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

SERIES ESTABLISHED: Garfield County, (Panguitch Soil Survey Area) Utah 1984.

REMARKS: Diagnostic horizons and features recognized in this pedon:

Mollic epipedon - from the surface to 10 inches (A, Bt horizons)
Argillic horizon - from 6 to 15 inches (Bt, Btk horizon)
Petrocalcic horizon - at 15 inches (Bkm horizon)

The 08/2011 revision restricts the moisture regime and subclass to aridic-ustic, with Upland ecological sites. The Semidesert sites previously included with this series are now excluded. Accordingly precipitation is narrowed from 9-14 to 12-14 inches.

At the type location and other locations where the parent material is alluvium it is possible the landforms are remnants of old dissected fan remnants or pediments rather than "mountainsides and ridges".

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National Cooperative Soil Survey
U.S.A.