LOCATION RED POINT WY
Tentative Series
IRD. IGC-JCK
07/2015
RED POINT SERIES
The Red Point series consist of deep, well drained soils that formed in slope alluvium or colluvium over residuum from interbedded sandstone and shale. Red Point soils are on eroded fan remnants and pediments. Slopes range from 3 to 15 percent. Mean annual precipitation is about 191 mm, and mean annual air temperature is about 7 degrees C.
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Typic Haplocalcids
TYPICAL PEDON: Red Point fine sandy loam, 5 percent slope in rangeland at an elevation of 1,503 meters (colors are for dry soil unless otherwise noted).
A--0 to 4 cm; pale brown (10YR 6/3) fine sandy loam, brown (10YR 4/3) moist; weak medium granular structure; loose; nonsticky and nonplastic; many very fine roots throughout; few very fine vesicular pores; 2 percent gravel; strongly effervescent; moderately alkaline (pH 8.1); clear smooth boundary. (3 to 6 cm thick)
Bw1--4 to 17 cm; brown (10YR 5/3) fine sandy loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and fine roots throughout; common very fine and fine tubular pores; 1 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); gradual wavy boundary.
Bw2--17 to 55 cm; yellowish brown (10YR 5/6) fine sandy loam, dark yellowish brown (10YR 4/6) moist; weak medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine roots throughout; common very fine and fine tubular pores; 1 percent gravel; strongly effervescent; moderately alkaline (pH 8.4); gradual wavy boundary. (combined thickness of Bw horizons is 40 to 51 cm)
Bk1--55 to 72 cm; very pale brown (10YR 7/4) fine sandy loam, light yellowish brown (10YR 6/4) moist; moderate medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; few fine and medium roots throughout; common very fine and fine tubular pores; 8 percent fine irregular calcium carbonate masses in the matrix; violently effervescent; strongly alkaline (pH 8.6); gradual wavy boundary.
Bk2--72 to 104 cm; yellowish brown (10YR 5/6) sandy loam, dark yellowish brown (10YR 4/6) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few fine roots throughout; common very fine and fine tubular pores; 30 percent fine irregular calcium carbonate masses in the matrix and 15 percent calcium carbonate nodules on the bottom of the rock fragments; 1 percent gravel; violently effervescent; strongly alkaline (pH 8.6); gradual wavy boundary. (Combined thickness of the Bk horizons is 49 to 63 cm thick)
Cr--104 to 150 cm; weakly cemented, calcareous sandstone.
TYPE LOCATION: Park County, Wyoming; 251 meters north and 232 meters east of the southwest corner of section 27, T. 52 N., R. 98 W.; YU Bench NW USGS quadrangle; latitude 44 degrees 26 minutes 44.65 seconds N. and longitude 108 degrees 37 minutes 52.40 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
Paralithic contact: 100 to 150 cm
A horizon:
Hue: 7.5YR to 2.5Y
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2, 3 or 4
Texture: fine sandy loam or sandy loam
Clay content: 8 to 18 percent
Rock fragments: 0 to 15 percent gravel
Reaction: pH 7.6 to 8.2
Bw horizons:
Hue: 7.5YR to 2.5Y
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 3, 4 or 6
Texture: fine sandy loam or sandy loam
Clay content: 10 to 18 percent
Rock fragments: 0 to 15 percent gravel
Reaction: pH 7.6 to 8.4
Bk horizons:
Hue: 7.5YR to 2.5Y
Value: 5, 6 or 7 dry, 4, 5 or 6 moist
Chroma: 3, 4 or 6
Texture: fine sandy loam or sandy loam
Clay content: 10 to 18 percent
Rock fragments: 0 to 15 percent gravel
Calcium carbonate equivalent: 8 to 16
Sodium adsorption ratio: 0 to 5
Reaction: pH 8.2 to 8.8
COMPETING SERIES:
Bluchief (UT) - have a lithic contact at depths of 50 to 100 cm; have hue redder than 7.5YR
Boreham (UT) - have more than 18 percent clay in the particle-size control section; do not have a paralithic contact at depths of 100 to 150 cm
Hiko Springs (UT) - do not have a paralithic contact at depths of 100 to 150 cm; have more than 15 percent rock fragments in the particle-size control section
Kaito (AZ) - do not have a cambic horizon; have hue redder than 7.5YR
Kinan (AZ) - do not have a paralithic contact at depths of 100 to 150 cm; have hue redder than 7.5YR
Mccutchen (NV) - have a lithologic discontinuity; do not have a paralithic contact at depths of 100 to 150 cm
Moffat (UT) - do not have a paralithic contact at depths of 100 to 150 cm; have hue redder than 7.5YR
Nakai (UT) - do not have a paralithic contact at depths of 100 to 150 cm; have hue redder than 7.5YR
Nakoy (UT) - do not have a paralithic contact at depths of 100 to 150 cm
Nolava (UT) - have more than 18 percent clay in the particle-size control section; do not have a paralithic contact at depths of 100 to 150 cm
Nuahs (NV) - do not have a paralithic contact at depths of 100 to 150 cm; have more than 15 percent rock fragments in the particle-size control section
Pagina (AZ) - have a paralithic contact at depths of 50 to 100 cm; have hue redder than 7.5YR
Riemod (UT) - have a horizon of gypsum accumulation; have more than 18 percent clay in the particle-size control section
Teabrush (UT) - do not have a paralithic contact at depths of 100 to 150 cm; have hue redder than 7.5YR
Trook (WY) - do not have a cambic horizon; do not have a paralithic contact at depths of 100 to 150 cm
GEOGRAPHIC SETTING:
Landform - eroded fan remnants and pediments
Elevation - 1,085 - 1,600 meters
Slope - 3 to 15 percent slopes
Parent material - slope alluvium or colluvium over residuum
Mean annual precipitation - 127 to 229 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 permeability.
USE AND VEGETATION: Red Point soils are generally used as rangeland; however, there are isolated areas of irrigated hayland and cropland. Principle native plants are rhizomatous wheatgrasses, needleandthread, Indian ricegrass, prairie Junegrass, bluebunch wheatgrass, and Wyoming big sagebrush. As this site deteriorates blue grama and threadleaf sedge become the dominate vegetation, with only traces of the reference species persisting.
DISTRIBUTION AND EXTENT: Red Point 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, 2015. The name is taken from a local landform.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from 0 to 4 cm (A horizon)
Cambic horizon - from 4 to 55 cm (Bw1 and Bw2 horizons)
Calcic horizon - from 55 to 104 cm (Bk1 and Bk2 horizons)
Paralithic contact - at 104 cm (Cr horizon)
Particle-size control section - from 25 to 100 cm (part of the Bw2, Bk1, and Bk2 horizons)
Red Point soils have a mesic temperature regime and an aridic moisture regime.
National Cooperative Soil Survey
U.S.A.