LOCATION RALSTONFLATS WY
Tentative Series
Rev. DEW-JCK
05/2023
RALSTONFLATS SERIES
The Ralstonflats series consists of very deep, well drained soils that formed in alluvium or colluvium. Ralstonflats soils are on fan remnants and stream terraces. Slopes range from 0 to 15 percent. Mean annual precipitation is about 309 mm, and the mean annual air temperature is about 7 degrees C.
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Ustic Haplocalcids
TYPICAL PEDON: Ralstonflats sandy loam, on a 1 percent slope in rangeland at an elevation of 1,581 meters (colors are for dry soil unless otherwise noted).
A--0 to 3 cm; brown (10YR 5/3) sandy loam, dark brown (10YR 3/3) moist; weak thin platy structure parting to weak fine granular; soft, very friable, slightly sticky, slightly plastic; many fine and medium roots throughout; many very fine interstitial pores; slightly effervescent; slightly alkaline (pH 7.8); clear smooth boundary. (3 to 10 cm thick)
Bw--3 to 13 cm; brown (10YR 5/3) fine sandy loam, brown (10YR 4/3) moist; weak coarse angular blocky structure parting to weak medium granular; slightly hard, friable, slightly sticky, slightly plastic; many fine and medium roots throughout; many very fine and fine tubular pores; slightly effervescent; slightly alkaline (pH 7.8); clear smooth boundary. (5 to 14 cm thick)
Bk1--13 to 23 cm; pale brown (10YR 6/3) fine sandy loam, brown (10YR 5/3) moist; weak coarse angular blocky structure; slightly hard, very friable, nonsticky, nonplastic; many fine and medium roots; many very fine and fine tubular pores; many very fine dark yellowish brown (10YR 3/4) organic stains on faces of peds; many very fine and fine calcium carbonate masses; strongly effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (10 to 40 cm thick)
Bk2--23 to 53 cm; very pale brown (10YR 7/3) fine sandy loam, yellowish brown (10YR 5/4) moist; weak fine and medium angular blocky structure; soft, very friable, nonsticky, nonplastic; common fine and medium roots; many very fine and fine tubular pores; many very fine dark yellowish brown (10YR 3/4) organic stains on faces of peds; many fine and medium calcium carbonate masses; violently effervescent; strongly alkaline (pH 8.6); gradual wavy boundary. (25 to 60 cm thick)
BCk1--53 to 81 cm; very pale brown (10YR 7/3) loamy sand, yellowish brown (10YR 5/4) moist; massive; soft, very friable, nonsticky, nonplastic; few fine roots throughout; many very fine and fine interstitial pores; many medium and coarse calcium carbonate masses; violently effervescent; strongly alkaline (pH 8.6); gradual wavy boundary. (0 to 30 cm thick)
BCk2--81 to 200 cm; very pale brown (10YR 8/4) loamy sand, yellowish brown (10YR 5/4) moist; massive; loose, nonsticky, nonplastic; few fine roots; many fine and very fine interstitial pores; finely disseminated carbonates, many medium, coarse, and very coarse threadlike and dendritic calcium carbonate masses, and few carbonate coats on rock fragments; 5 percent gravel; violently effervescent; strongly alkaline (pH 8.8).
TYPE LOCATION: Park County, Wyoming; 243 meters north and 121 meters east of the southwest corner of section 16, T. 55 N., R. 101 W.; Eaglenest Basin NE USGS quadrangle; latitude 44 degrees 44 minutes 25.413 seconds N. and longitude 109 degrees 2 minutes 12.26 seconds W., NAD 83.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 8 to 10 degrees C
Particle-size control section (weighted average) - more than 50% fine sand or coarser sand
Notes: The Bk horizons contain more than 50% (by weight) fine sand or coarser sand. Rock fragments are less than 15% throughout the profile.
A horizon
Hue: 10YR or 2.5Y
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 2 or 3
Texture: sandy loam, loam, and fine sandy loam
Clay content: 10 to 22
Rock fragments: 0 to 10 percent gravel
Reaction: pH 7.6 to 8.0
Bw horizon
Hue: 10YR or 2.5Y
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 3 or 4
Texture: loam, fine sandy loam, and sandy loam
Clay content: 12 to 20 percent
Rock fragments: 0 to 5 percent gravel
Reaction: pH 7.6 to 8.0
Bk horizons
Hue: 10YR or 2.5Y
Value: 7 or 8 dry, 4 to 6 moist
Chroma: 3 or 4
Texture: fine sandy loamy or sandy loam
Clay content: 10 to 18 percent
Rock fragments: 0 to 15 percent gravel
Calcium Carbonate equivalent: 10 to 30 percent
Reaction: pH 8.0 to 8.6
BCk horizons
Hue: 10YR or 2.5Y
Value: 7 or 8 dry, 4 to 6 moist
Chroma: 3 or 4
Texture: sandy loam, loamy sand, loamy fine sand, or sand
Clay content: 5 to 15 percent
Rock fragments: 0 to 15 percent
Calcium carbonate equivalent: 5 to 30 percent
Sodium adsorption ratio: 0 to 5
Reaction: pH 8.0 to 8.8
COMPETING SERIES:
Abracon (UT) - have more than 18 percent clay in the particle-size control section
ThumbRock (UT) - have a lithic contact at depths of 50 to 100 cm; have hue redder than 10YR
Chroder (CO) - have a cambic horizon; have hue redder than 10YR
Chugcity (WY) - have a paralithic contact at depths of 50 to 100 cm
Chupadera (NM) - have a lithic contact at depths of 50 to 100 cm
Cobbra (UT) - have more than 18 percent clay in the particle-size control section; have more than 15 percent rock fragments in the lower part of the subsoil
Harvey (NM) - have more than 18 percent clay in the particle-size control section; have hue redder than 10YR
Kaiar (UT) - have a cambic horizon; have a lithic contact at depths of 50 to 100 cm
Kamms (WY) - have more than 15 percent rock fragments in the subsoil
Milok (UT) - have a cambic horizon; have hue redder than 10YR
Mivida (UT) - have a cambic horizon; have hue redder than 10YR
Nala (NM) - have a lithologic discontinuity; have more than 15 percent rock fragments throughout the profile
Sazi (UT) - have a lithic contact at depths of 50 to 100 cm; have hue redder than 10YR
Smithpond (UT) - have a cambic horizon; have more than 15 percent rock fragments in the lower part of the subsoil
Yattle (CO) - have a cambic horizon; have hue redder than 10YR
GEOGRAPHIC SETTING:
Landform - fan remnants and stream terraces
Elevation - 1,100 - 1,600 meters
Slope - 0 to 15 percent slopes
Parent material - alluvium or colluvium
Mean annual precipitation - 250 to 360 mm
Mean annual air temperature - 6 to 8 degrees C
Frost-free period - 110 to 150 days
GEOGRAPHICALLY ASSOCIATED SOILS: None listed.
DRAINAGE AND PERMEABILITY: Well drained; moderately rapid and rapid permeability.
USE AND VEGETATION: These soils are used for irrigated cropland or for grazing. Alfalfa hay, barley, corn, sugar beets, and beans are the principal crops. The native plant community is needle and thread, thickspike wheatgrass, Indian ricegrass, Wyoming big sagebrush, and western wheatgrass.
DISTRIBUTION AND EXTENT: Ralstonflats soils are of small extent in northwestern Wyoming. MLRA 32.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Park County Area, Wyoming, Eastern Part, 2014. The original series concept (Bessler) was developed in 1983. The name is taken from a local landform name.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from 0 to 13 cm (A and Bw horizons)
Calcic horizon - from 13 to 200 cm (Bk1, Bk2, BCk1, and BCk2 horizons)
Particle-size control section - from 25 to 100 cm (part of the Bw, Bk1, Bk2, BCk1, and BCk2 horizons)
Ralstonflats soils have a mesic temperature regime and an aridic moisture regime bordering on ustic.
ADDITIONAL DATA: Kellogg Soil Survey Laboratory - 79P0213, 79P0216.
National Cooperative Soil Survey
U.S.A.