LOCATION LECKMAN WYTentative Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, calcareous, frigid Typic Torriorthents
TYPICAL PEDON: Leckman fine sandy loam-rangeland. (Colors are for dry soil unless otherwise stated.)
A11--0 to 2 inches; light grayish brown (10YR 6/2) fine sandy loam, dark grayish brown (10YR 4/2) moist; weak medium platy structure breaks to weak fine crumbs; soft, very friable, nonsticky, nonplastic; slightly effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary. (1 to 3 inches thick)
A12--2 to 12 inches; light grayish brown (10YR 6/2) fine sandy loam, dark grayish brown (10YR 4/2) moist; weak coarse and medium prismatic structure that parts to weak medium subangular blocks; soft, very friable, nonsticky, nonplastic; strongly effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (6 to 15 inches thick)
C--12 to 60 inches; light grayish brown (10YR 6/2) fine sandy loam, dark grayish brown (10YR 4/2) moist; massive, soft very friable nonsticky, nonplastic; strongly effervescent, moderately alkaline (pH 8.4)
TYPE LOCATION: Sweetwater County, Wyoming; 400 feet north and 400 feet west of southeast corner section 32, T 23 N, R 110 W. Seedskadee Demonstration Farm along the Green River.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is about 43 to 47 degrees F. The mean summer soil temperature is 64 to 67 degrees F. Textures throughout the profile are fine sandy loam or sandy loam. Gravel content is generally less than 5 percent but can range from 0 to 15 percent.
The A horizons have hues of 10YR or 2.5Y, values of 6 or 7 dry and 4 or 5 moist, and chromas of 2 through 4.
The C horizon has hues of 10YR or 2.5Y, values of 6 or 7 dry and 4 or 5 moist, and chromas of 2 through 4. Reaction is moderately or strongly alkaline. Effervesence may be slight to violent.
COMPETING SERIES: This is the Terada series which has a paralithic content at 20 to 40 inches.
GEOGRAPHIC SETTING: Leckman soils are on alluvial fans and toe slopes of escarpments. Slopes are 0 to 10 percent. The soils formed in alluvium. Elevation is 6,000 to 7,000 feet. The mean annual precipitation is 7 to 9 inches. The mean annual air temperature is 37 to 44 degrees F. The frost-free season is 80 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dinco, Pepal and Quealman soils. Dinco soils are coarse-silty. Pepal soils have a calcic horizon. Quealman soils are fluvents.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderately rapid permeability. Some of these areas receive a little additional moisture from run-in.
USE AND VEGETATION: These soils are used mainly for grazing and wildlife habitat. Native vegetation is mainly big sagebrush, shadscale, spiny horsebrush, rabbitbrush, thickspike wheatgrass, bluebunch wheatgrass, Indian ricegrass, needleandthread, winterfat and phlox. Some minor areas are in urban developments for which they are well suited. These soils are well suited to irrigated cropland where water is available.
DISTRIBUTION AND EXTENT: Throughout southwestern Wyoming. These soils are of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Sweetwater County, 1976.
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 Lakewood MLRA office, without review of the soil series property data. The remainder of this document has not been updated.