LOCATION RAZSUN WYEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, mesic Ustic Haplogypsids
TYPICAL PEDON: Razsun clay loam--rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 3 inches; light brownish gray (2.5Y 6/2) clay loam, dark grayish brown (2.5Y 4/2) moist; weak medium platy structure parting to moderate medium granular; slightly hard, friable, slightly sticky and slightly plastic; many fine and common medium roots; slightly effervescent, carbonates disseminated; moderately alkaline (pH 8.2); clear smooth boundary. (2 to 3 inches thick)
Bw--3 to 11 inches; light brownish gray (2.5Y 6/2) clay, dark grayish brown (2.5Y 4/2) moist; weak medium prismatic structure parting to moderate medium subangular blocky; hard, firm, sticky and plastic; common fine and few coarse roots; slightly effervescent, carbonates disseminated; moderately alkaline (pH 8.4); clear wavy boundary. (7 to 18 inches thick)
By--11 to 21 inches; grayish brown (2.5Y 5/2) clay, dark grayish brown (2.5Y 4/2) moist; massive; hard, firm, sticky and plastic; common fine and few coarse roots; slightly effervescent, carbonates disseminated; 25 percent gypsum; common threads and seams of gypsum, 75 percent soft shale fragments; moderately alkaline (pH 8.0). (6 to 20 inches thick)
Cr--21 to 60 inches; soft, platy, gypsiferous shale.
TYPE LOCATION: Natrona County, Wyoming; 1,650 feet north and 2,400 feet west of the SE corner of sec. 27, T. 40 N., R. 82 W.
RANGE IN CHARACTERISTICS: Organic carbon in the upper 40 centimeters averages 1 to 2 percent. Depth to bedrock ranges from 20 to 40 inches. Depth to the base of the cambic horizon and depth to the gypsic horizon ranges from 10 to 20 inches. The particle-size control section is clay loam or clay with 35 to 45 percent clay and less than 35 percent fine sand or coarser. The mean annual soil temperature is 50 to 52 degrees F.
The A horizon has hue of 10YR or 2.5Y, value of 5 or 6 dry, and 4 or 5 moist. EC is less than 2 mmhos.
The Bw horizon has hue of 10YR or 2.5Y, value of 5 or 6 dry, and 4 or 5 moist. It is clay loam or clay. EC is less than 4 mmhos.
The By horizon has value of 5 or 6 dry, and 4 or 5 moist. It has 40 to 80 percent soft shale fragments which break down on pretreatment. Gypsum ranges from 10 to 30 percent. EC ranges from 2 to 8 mmhos. It is mildly alkaline or moderately alkaline.
The Cr is soft, platy, gypsiferous shale. It commonly is more than 20 feet thick.
COMPETING SERIES: These are the Blueflat, Chipendale, and Lonebear series. Blueflat soils have mean annual soil temperatures of 54 to 57 degrees F. Chipendale and Lonebear soils are deep.
GEOGRAPHIC SETTING: Razsun soils are on hillsides and footslopes. Slopes range from 5 to 15 percent. They formed in slopewash alluvium and residuum derived from gypsiferous shale. The mean annual precipitation ranges from 10 to 14 inches with peak periods of precipitation occurring in April, May, and June. The mean annual temperature ranges from 48 to 51 degrees F. Elevation ranges from 5,000 to 5,500 feet. The frost-free season is 120 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chipenhill and the competing Chipendale and Lonebear soils. Chipenhill soils are shallow and do not have a gypsic horizon.
DRAINAGE AND PERMEABILITY: Well drained; rapid runoff; slow permeability.
USE AND VEGETATION: Razsun soils are used for livestock grazing and wildlife habitat. Native vegetation is mainly green needlegrass, western wheatgrass, prairie junegrass and big sagebrush.
DISTRIBUTION AND EXTENT: Central Wyoming. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Natrona County, Wyoming; 1985.