LOCATION MAINTER WYEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Aridic Argiustolls
TYPICAL PEDON: Mainter fine sandy loam - cultivated. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 8 inches; brown (10YR 5/3) fine sandy loam, dark brown (10YR 3/3) moist; weak coarse subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine roots throughout; common very fine sontinuous interstitial pores; slightly alkaline (pH 7.4); abrupt smooth boundary. (8 to 16 inches thick)
Bt1--8 to 12 inches; yellowish brown (10YR 5/4) fine sandy loam, brown (10YR 4/3) moist; weak coarse prismatic structure parting to weak medium subangular blocky; hard, friable, slightly sticky and slightly plastic; common very fine and fine roots throughout; common very fine and few fine continuous interstitial pores; common distinct clay films on faces of peds; slightly alkaline (pH 7.6); clear smooth boundary.
Bt2--12 to 20 inches; yellowish brown (10YR 5/4) fine sandy loam, brown (10YR 4/3) moist; weak very coarse prismatic structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine roots throughout; common very fine and few fine continuous interstitial pores; common faint clay films on faces of peds; slightly alkaline (pH 7.6); gradual wavy boundary. (Combined thickness of the Bt horizon is 7 to 21 inches thick)
Bk--20 to 60 inches; very pale brown (10YR 7/3) fine sandy loam, yellowish brown (10YR 5/4) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots throughout; common very fine continuous interstitial pores; strongly effervescent, calcium carbonate disseminated, 4 percent calcium carbonate equivalent; moderately alkaline (pH 8.0).
TYPE LOCATION: Platte County, Wyoming; 7 miles northeast of Chugwater; approximately 1, 700 feet west and 350 feet south of the northeast corner of Sec. 30, T. 21 N., R. 65 W.
RANGE IN CHARACTERISTICS: The mollic epipedon is from 8 to 16 inches thick. The particle size control section is 13 to 18 percent clay, with 15 to 35 percent fine sand or coarser. Depth to horizons which contain calcium carbonate is 14 to 30 inches.
The A horizon has value of 4 or 5 dry and chroma of 2 or 3. Texture is fine sandy loam or very fine sandy loam. The reaction is neutral or slightly alkaline.
The Bt horizon has value of 4 through 6 dry, and chroma of 3 or 4. Texture is fine sandy loam or very fine sandy loam. The reaction is neutral through moderately alkaline.
The Bk horizon has value of 6 or 7 dry, 5 or 6 moist, and chroma of 3 or 4 moist. Texture is fine sandy loam, very fine sandy loam, sandy loam, or loam. The reaction is slightly alkaline or moderately alkaline. Calcium carbonate equivalent ranges from 4 to 14 percent.
COMPETING SERIES: These are the Julesburg (CO), Manter (CO), Mawer (SD), Torrington (WY), and Truckton (CO) series. Julesburg soils are noncalcareous and have a coarse textured C horizon above a depth of 40 inches. Manter soils have mean annual moistures and temperatures that are a little higher and have greater than 35 percent fine or coarser sand in the particle size control section. Mawer soils have a noncontrasting sand and gravel substratum at a depth of 20 to 40 inches. Torrington soils have a paralithic contact between 20 to 40 inches. Truckton soils are noncalcareous.
GEOGRAPHIC SETTING: Mainter soils are on hills and benches. Slopes are 0 to 10 percent. The soil formed in alluvium and eolian materials. The average annual precipitation is 12 to 15 inches. Mean annual air temperature is 46 to 48 degrees F. The frost-free season is 110 to 130 days. Elevation is 4,300 to 5,700 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Jayem, Keeline, and Moskee series. Jayem and Keeline soils do not have argillic horizons and Keeline also has an ochric epipedon. Moskee soils have a fine-loamy control section.
DRAINAGE AND PERMEABILITY: Moderately well and well drained; low runoff; moderately rapid permeability.
USE AND VEGETATION: These soils are used for native rangeland or for dry or irrigated cropland. Native vegetation consists mainly of blue grama, thickspike wheatgrass, needleandthread, sand bluestem, and silver sagebrush.
DISTRIBUTION AND EXTENT: Southeastern Wyoming; MLRA 64 and 67; The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES PROPOSED: Platte County, Wyoming, 1997.
REMARKS: Diagnostic features in this soil include a mollic epipedon from 0 to 8 inches and an argillic horizon from 8 to 20 inches.