LOCATION WORFKA             WY+MT
Established Series
GFK/CAP/CJH
12/2005

WORFKA SERIES


The Worfka series consists of well drained soils that are very shallow or shallow to bedrock. They formed in slopewash alluvium and residuum derived from interbedded calcareous shale and argillaceous sandstone. Worfka soils are on uplands, ridges and hills. Slopes are 0 to 30 percent. The mean annual precipitation is about 13 inches, and the mean annual air temperature is about 46 degrees F.

TAXONOMIC CLASS: Clayey, smectitic, mesic, shallow Ustic Haplargids

TYPICAL PEDON: Worfka clay loam-rangeland. (Colors are for dry soil unless otherwise stated)

A--0 to 2 inches; light brownish gray (10YR 6/2) light clay loam, dark grayish brown (10YR 4/2) moist; moderate very fine granular structure; hard, friable, sticky and plastic; many fine and very fine roots; neutral (pH 7.2); clear smooth boundary. (1 to 4 inches thick)

Bt--2 to 7 inches; grayish brown (10YR 5/2) clay loam, dark grayish brown (10YR 4/2) moist; moderate medium angular blocky structure parting to moderate fine angular blocky; very hard, firm, sticky and plastic; many fine and very fine roots; many prominent clay films on faces of peds; slightly alkaline (pH 7.4); clear smooth boundary. (3 to 8 inches thick)

Btk--7 to 13 inches; pale brown (10YR 6/3) clay loam, brown (10YR 5/3) moist; strong medium angular blocky structure; very hard, firm, sticky and plastic; common fine and medium roots; few distinct clay films on faces of peds; strongly effervescent, calcium carbonate as few soft masses; moderately alkaline (pH 8.2); clear smooth boundary. (0 to 6 inches thick)

Bk--13 to 19 inches; light brownish gray (10YR 6/2) clay loam, grayish brown (10YR 5/2) moist; medium coarse subangular blocky structure; very hard, firm, sticky and plastic; violently effervescent, calcium carbonate as common medium soft masses; moderately alkaline (pH 8.4); clear wavy boundary. (3 to 9 inches thick)

Cr--19 to 60 inches; soft, calcareous shale.

TYPE LOCATION: Campbell County, Wyoming; 1700 feet east and 2490 north of the southwest corner of sec. 5, T. 48 N., R. 70 W. Coyote Draw Quadrangle. 44 degrees 10 minutes 2 seconds north latitude and 105 degrees 20 minutes 8 seconds west longitude.

RANGE IN CHARACTERISTICS: Depth to carbonates ranges from 4 to 12 inches. Depth to bedrock ranges from 7 to 20 inches. The control section is clay loam or clay and averages 35 to 50 percent clay and more than 15 percent fine or coarser sand. The soils are dry in the moisture control section more than half the time cumulative that the soil temperature at a depth of 20 inches is 41 degrees F., which occurs about April 21-27, and is dry in all parts of the moisture control section for at least 60 consecutive days from July 15 to October 25 and for at least 90 cumulative days during this period. The mean soil temperature is 47 to 53 degrees F., and the soil temperature at a depth of 20 inches is 41 degrees F. or more for 175 to 192 days. Channers range from 0 to 15 percent, are typically less than 5 percent, and break down with pretreatment.

The A horizon has hue of 2.5Y or 10YR, value of 5 or 6 dry, 3 to 5 moist, and chroma of 2 or 3. It is loam, clay loam, fine sandy loam or very fine sandy loam. Reaction is neutral or slightly alkaline.

The Bt horizon has hue of 2.5Y or 10YR, value of 5 or 6 dry, 4 or 5 moist, and chroma is 2 to 4. Texture is clay or clay loam. Reaction is neutral to strongly alkaline.

The Btk, when present, has hue of 2.5Y or 10YR, value of 5 or 7 dry, 4 to 6 moist, and chroma is 2 to 4. Texture is clay or clay loam. Reaction is slightly alkaline or moderately alkaline. Calcium carbonate equivalent is 3 to 12 percent.

The Bk horizon has hue of 2.5Y or 10YR, value of 5 to 7 dry, 5 or 6 moist, and chroma of 2 to 4. Texture is clay or clay loam. Reaction is moderately alkaline or strongly alkaline. Calcium carbonate equivalent is 5 to 14 percent.

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING: Worfka soils are on ridge crests, shoulders, footslopes, and toeslopes. Slopes are 0 to 30 percent. The soils formed in alluvium and residuum weathered from calcareous shales and argillaceous sandstone. Elevation is 3,500 to 6,500 feet. The mean annual precipitation is 13 inches with over half of the annual precipitation falling in April, May, and June and less than one inch falling in each month of July, August, September, and October. Precipitation ranges from 10 to 14 inches. The mean annual temperature ranges from 44 to 51 degrees F. The frost-free period is about 150 to 130 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Samday, Shingle, Renohill, and Tassel soils. Samday, Shingle, and Tassel soils lack argillic horizons. Renohill soils have bedrock at depths of 20 to 40 inches.

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

USE AND VEGETATION: Rangeland and wildlife habitat. Native vegetation is bluebunch wheatgrass, blue grama, western wheatgrass, big sagebrush, green needlegrass, and needleleaf sedge.

DISTRIBUTION AND EXTENT: The plains of northeastern Wyoming and the basins of north-central Wyoming. The series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado

SERIES ESTABLISHED: Converse and Weston Counties, Wyoming; 1983.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - 0 to 2 inches (A)

Argillic Horizon - 2 to 13 inches (Bt,Btk)

Paralithic Contact - 19 inches (Cr)

MLRR- G

SIR- WY1292


National Cooperative Soil Survey
U.S.A.