LOCATION CHRISMAN WYTentative Series
TAXONOMIC CLASS: Fine, mixed, superactive, calcareous, frigid Typic Torrifluvents
TYPICAL PEDON: Chrisman silty clay, rangeland. (Colors are for dry soil unless otherwise stated.)
A11--0 to 2 inches; light brownish gray (2.5Y 6/2) silty clay, dark grayish brown (2.5Y 4/2) moist; weak very fine angular blocky structure; hard, friable, very sticky and plastic; strongly effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary.
A12--2 to 7 inches; light brownish gray (2.5Y 6/2) silty clay, light olive brown (2.5Y 5/4) moist; weak thin platy parting to moderate medium granular structure; hard, friable, very sticky and plastic; few very fine and fine roots; strongly effervescent; moderately alkaline (pH 8.2); clear wavy boundary.
C1--7 to 33 inches; light yellowish brown (2.5Y 6/4) silty clay, light olive brown (2.5Y 5/4) moist; weak coarse subangular blocky parting to weak very fine angular blocky structure; very hard, friable, very sticky and plastic; common medium and coarse roots; strongly effervescent; moderately alkaline (pH 8.2); gradual wavy boundary.
C2--33 to 45 inches; light yellowish brown (2.5Y 6/4) silty clay, light olive brown (2.5Y 5/4) moist; weak medium and fine angular blocky structure with some slickenslides; very hard, friable, very sticky and plastic; very few, very fine and medium roots; strongly effervescent; moderately alkaline (pH 8.2); gradual wavy boundary.
C3--45 to 60 inches; light yellowish brown (2.5Y 6/4) silty clay, light olive brown (2.5Y 5/4) moist; weak medium and fine angular blocky structure; very hard, friable, very sticky and plastic; strongly effervescent; moderate alkaline (pH 8.2) .
TYPE LOCATION: Sweetwater County, Wyoming; Sec. 20, T.l9N., R.lOOW., 1,300 feet east and 300 feet south of NW corner.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 45 degrees to 47 degrees F. and the mean summer temperature is 62 degrees to 68 degrees F. The control section is typically silty clay, silty clay loam with clay ranging from 35 to 60 percent. There may be a few pebbles scattered over the surface; coarse fragments range from O to 5 percent.
The A horizon has hue of 10YR through 5Y; value of 5 through 7 dry, 4 through 6 moist; and chroma of 2 through 4. It is typically silty clay but may be silty clay loam or clay. Reaction is moderately or strongly alkaline.
The C horizon has hue of 10YR through 5Y; value of 5 or 6 dry, 4 through 6 moist; and chroma of 3 or 4. It is typically silty clay but may be clay or heavy silty clay loam. Reaction is moderately to very strongly alkaline. The EC ranges from 4 to 16 mmhos throughout. Slickensides are common as are pressure faces.
COMPETING SERIES: None in this family and subgroup.
GEOGRAPHIC SETTING: Chrisman soils are on level and nearly level basins and alluvial fans. Slopes are O to 2 percent. The soils formed in fine-textured alluvium and older lacustrine sediments. Elevation is 6,000 to 6,700 feet. The mean annual precipitation is 6 to 9 inches and occurs mainly in the winter and spring. The mean annual air temperature is 42 degrees to 45 degrees F., the mean summer air temperature is 63 degrees to 66 degrees F. The frostfree season is 80 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are Dines soils which occupy the same landscape and are in the fine-silty family.
DRAINAGE AND PERMEABILITY: Moderately well drained, slow runoff; very slow permeability.
USE AND VEGETATION: These soils have limited use for grazing and wildlife habitat. Native vegetation is mainly sparse with small clumps of greasewood, Gardner saltbush, and bottlebrush squirreltail. About 90 percent of the surface is barren.
DISTRIBUTION AND EXTENT: Southwestern Wyoming, the series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Sweetwater County, Wyoming, 1978. The name is that of an old ranch in the county.
OSED scanned by NSSQA. Last revised by state on 5/79.
REMARKS:
The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data. The remainder of this document has not been updated.