LOCATION RHOAME             WY
Established Series
Rev. PSD
02/97

RHOAME SERIES


The Rhoame series consists of deep, well drained soils that formed in sediments derived mainly from partly metamorphosed shale. Rhoame soils are on alluvial fans and valley-filling sideslopes and have slopes of 0 to 20 percent. The mean annual precipitation is about 12 inches, and the mean annual temperature is about 46 degrees F.

TAXONOMIC CLASS: Fine, smectitic, nonacid, mesic Ustic Torriorthents

TYPICAL PEDON: Rhoame channery clay loam-grassland. (Colors are for dry soils unless otherwise stated.)

A--0 to 4 inches; light brownish gray (10YR 6/2) channery clay loam, dark grayish brown (10YR 4/2) moist; strong fine granular structure; soft, very friable, sticky and plastic; 20 percent slate and hard shale fragments; neutral (pH 6.8); clear smooth boundary. (3 to 6 inches thick)

AC--4 to 8 inches; grayish brown (10YR 5/2) channery clay loam, dark grayish brown (10YR 4/2) moist; weak coarse subangular blocky structure; slightly hard, very friable, sticky and plastic; 20 percent slate and hard shale fragments; slightly acid (pH 6.4); gradual smooth boundary. (0 to 5 inches thick)

C--8 to 60 inches; brown (10YR 5/3) channery clay, dark brown (10YR 4/3) moist; massive; hard, firm, very sticky and very plastic; 25 percent slate and hard shale fragments; slightly acid (pH 6.5).

TYPE LOCATION: Johnson County, Wyoming; SE1/4, SE1/4 sec. 16, T. 41 N., R. 81 W.

RANGE IN CHARACTERISTICS: Coarse fragments are usually more than 15 percent and range from 0 to 35 percent. The matrix of the control section is clay loam or clay with clay ranging from 35 to 50 percent. The mean annual soil temperature ranges from 47 to 54 degrees F.

The soil has hue of 5Y through 10YR, value of 5 through 7 dry and 3 or 4 moist, and chroma of 2 or 3. It is slightly acid through mildly alkaline.

COMPETING SERIES: This is the Topeman series which has a paralithic contact at 20 to 40 inches.

2- Rhoame Series

GEOGRAPHIC SETTING: The Rhoame soils are on alluvial fans and valley-filling sideslopes. Slopes range from 0 to 20 percent. Elevation is 3,200 to 6,000 feet. These soils formed in thick, fine textured, noncalcareous sediments derived principally from the weathering of noncalcareous, partly metamorphosed shale. At the type location the mean annual precipitation is 12 inches with peak periods of precipitation during the spring and early summer. The mean annual temperature is 46 degrees F. The frost-free season is 95 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Moret and Shirk soils. Moret soils have a paralithic contact at depths of 10 to 20 inches. Shirk soils have a mollic epipedon and have a paralithic contact at depths of 20 to 40 inches.

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

USE AND VEGETATION: These soils are used principally as native rangeland; they are cultivated in some places where irrigation water is available. Principal native plants are western wheatgrass, silver sage, green needlegrass, and annuals.

DISTRIBUTION AND EXTENT: Northern Wyoming. The series is of moderate extent.

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

SERIES ESTABLISHED: Johnson County (Southern Johnson County Area), Wyoming; 1971.


National Cooperative Soil Survey
U.S.A.