LOCATION OLDWOLF WYEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Aridic Haplustalfs
TYPICAL PEDON: Oldwolf loam -- on a northwest facing slope of 4 percent, utilized as rangeland. (Colors are for dry soil unless otherwise stated)
A--0 to 5 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; weak medium and moderate fine granular structure; soft, friable, slightly sticky and slightly plastic; many fine and very fine, few medium roots; neutral (pH 6.8); clear smooth boundary. (1 to 6 inches thick)
Bt--5 to 14 inches; yellowish brown (10YR 5/4) clay loam, dark yellowish brown (10YR 4/4) moist; moderate medium prismatic structure parting to moderate medium and fine angular blocky; hard, friable, sticky and plastic; common fine and very fine, few medium roots; many distinct clay films on faces of peds; slightly alkaline (pH 7.4); clear smooth boundary. (5 to 25 inches thick)
Btk--14 to 21 inches; pale brown (10YR 6/3) clay loam, brown (10YR 5/3) moist; weak medium and fine prismatic structure parting to moderate medium and fine subangular blocky; slightly hard, friable, slightly sticky and plastic; few fine and very fine roots; common faint clay films on faces of peds and lining pores; strongly effervescent, calcium carbonate mostly disseminated; slightly alkaline (pH 7.8); clear wavy boundary. (0 to 11 inches thick)
Bk--21 to 35 inches; pale brown (10YR 6/3) loam, brown (10YR 5/3) moist; weak medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few fine and very fine roots; strongly effervescent, common fine filaments and soft masses, and few medium soft masses of calcium carbonate; moderately alkaline (pH 8.2); clear wavy boundary. (4 to 27 inches thick)
Cr--35 to 60 inches; yellowish brown (10YR 5/4) to light gray (10YR 7/2) silty sandy shale; inconsistently effervescent to about 40 inches and mostly noneffervescent below.
TYPE LOCATION: Campbell County, Wyoming; about 100 feet east and 2,300 feet south of the northwest corner of section 16, T. 48 N., R. 71 W. 44 degrees 08 minutes 20 seconds north latitude and 105 degrees 24 minutes 11 seconds west longitude.
RANGE IN CHARACTERISTICS: Depth to bedrock is commonly 26 to 35 inches but ranges from 20 to 40 inches. Depth to the base of the argillic horizon ranges from 15 to 32 inches. Depth to accumulations of calcium carbonate is typically 10 to 31 inches. The soil has less than 10 percent rock fragments throughout. The moisture control section is usually moist in some or all parts in March through June. The average annual soil temperature is 47 to 50 degrees F.
The A horizon has hue of 10YR or 2.5Y, value of 5 or 6 and 3 or 4 moist, and chroma of 2 to 4. It is clay loam, loam or fine sandy loam. It is neutral or slightly alkaline.
The Bt horizon has hue of 7.5YR, 10YR or 2.5Y, value of 5 or 6 and 4 or 5 moist, and chroma of 3 or 4. Texture is commonly clay loam and less commonly loam. It has 20 to 35 percent clay and 15 to 35 percent fine and coarser sand. It is neutral or slightly alkaline.
The Btk horizon has hue of 10YR or 2.5Y, value of 5 to 7 and 4 or 5 moist, and chroma of 2 to 4. It is typically part of the argillic horizon. It is clay loam or loam. It has 3 to 12 percent calcium carbonate equivalent. It is slightly alkaline or moderately alkaline.
The Bk horizon has hue of 10YR or 2.5Y, value of 5 to 7 and 4 to 6 moist, and chroma of 2 to 4. Texture is commonly loam or clay loam and less commonly silt loam or fine sandy loam. It has 4 to 14 percent calcium carbonate equivalent. It is moderately alkaline or strongly alkaline.
The Cr horizon consists of sandy or silty shale, or interbedded shale and sandstone. In a few pedons it is primarily sandstone. The bedrock may be strongly effervescent throughout, inconsistently effervescent in various layers, or noneffervescent.
COMPETING SERIES: These are the Arnor, Arwite, Augustine, Bigbow, Bosonoak, Carri, Celacy, Celavar, Dalhart, Deekay, Dermala, Elwop, Evpark, Flugle, Fort Collins, Gateson, Goesling, Iwela, Lykorly, Maia, Nomrah, Nyjack, Olnest, Orlie, Parkelei, Pinitos, Rauzi, Ribera, Rockybutte, Stoneham, Toluca and Wagonhound series. Arnor, Arwite, Augustine, Dalhart, Deekay, Dermala, Flugle, Fort Collins, Goesling, Iwela, Lykorly, Maia, Nomrah, Olnest, Orlie, Parkelei, Pinitos, Rauzi, Stoneham and Wagonhound soils are very deep. In addition, Arnor soils have more than 15 percent rock fragments. Bigbow soils have buried horizons at depths of less than 40 inches. Bosonoak soils occur above elevations of 6500 feet and receive most of their precipitation between July and October. Carri, Celavar, Evpark, Nyjack and Ribera soils have a lithic contact at 20 to 40 inches. Celacy soils are moist in some part of the moisture control section during the 120 days following the winter solstice. Elwop soils have more than 35 percent fine sand and coarser sand in the particle-size control section. Gateson soils have an E&B horizon. Toluca soils have secondary calcium carbonate accumulations at 10 inches or less and the base of the argillic horizon is less than 15 inches. Olnest soils have a frost-free period of more than 135 days. Rockybutte soils are moderately deep to porcellanite.
GEOGRAPHIC SETTING: Oldwolf soils are on fan remnants, plateaus, ridges and hills. They formed in alluvium over residuum derived from mixed sedimentary sources. Slopes are 0 to 15 percent. Elevations are 3,500 to 5,200 feet. The mean annual precipitation ranges from 15 to 17 inches, half of which falls as rain or snow in March through June. The mean annual air temperature ranges from 44 to 50 degrees. The frost-free season is about 105 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the completing Arwite, Deekay and Elwop soils and the Iwait, Jaywest, Lieter, Moorhead, Fairburn, Spottedhorse and Ucross soils. Arwite, Deekay, Iwait, Jayest and Moorhead soils occur on similar landscape positions. Lieter, Fairburn, Spottedhorse and Ucross soils occur on summit and shoulder slopes of hills and ridges. Iwait and Ucross lack argillic horizons and are calcareous throughout. Jaywest, Lieter Moorhead and Spottedhorse have a fine particle sized control section. Fairburn soils are shallow.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderate permeability.
USE AND VEGETATION: These soils are utilized primarily as rangeland, hayland and pasture, and wildlife habitat. The native vegetation is mainly needleandthread, western wheatgrass, blue grama, and green needlegrass.
DISTRIBUTION AND EXTENT: Oldwolf soils occur in the Powder River basin of north-central and northeastern Wyoming. The series is of limited extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Campbell County, Wyoming, Southern Part; 1995
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 5 inches (A)
Argillic horizon - 5 to 21 inches (Bt and Btk horizons)
LRR- G