LOCATION GRIMSTONE CO+WYEstablished Series
TAXONOMIC CLASS: Fine-loamy, micaceous Ustic Glossocryalfs
TYPICAL PEDON: Grimstone sandy loam - cut over land. (Colors are for dry soil unless otherwise noted.)
Oi--0 to 1 inches; undecomposed organic material, principally needles, bark, leaves, twigs, and the fleshy remains of grasses and shrubs.
Oe--1 to 2 inches; partially decomposed organic material like that of the horizon above.
A--2 to 4 inches; grayish brown (10YR 5/2) sandy loam, very dark grayish brown (10YR 3/2) moist; strong fine granular structure; soft, very friable, nonsticky, nonplastic; enough mica in small flakes to give the soil mass a soaplike consistency when moist and crushed; moderately acid (pH 5.8); abrupt smooth boundary. (0 to 5 inches thick)
E--4 to 14 inches; light brownish gray (10YR 6/2) sandy loam, grayish brown (10YR 5/2) moist; very weak thick platy structure parting to fine subangular blocky and then to medium granular; soft, very friable, nonsticky, nonplastic; enough mica in small flakes to give the soil mass a soaplike consistency when moist and crushed; moderately acid (pH 5.8); gradual wavy boundary. (4 to 17 inches thick)
E/B--14 to 22 inches; mixed light brownish gray (10YR 6/2) and yellowish brown (10YR 5/4) loam, grayish brown (10YR 5/2) and dark yellowish brown (10YR 4/4) moist; weak coarse subangular blocky structure parting to fine subangular blocky; slightly hard, very friable, slightly sticky, slightly plastic; enough mica in small flakes to give the soil mass a soaplike consistency when moist and crushed; thin glossy patches on some faces of peds and discontinuous glossy coatings in some root channels and pores in the more clayey portion of this horizon; this horizon consists of seams and nodules of clayey material like that of the underlying horizon embedded in a lighter colored matrix like that of the overlying horizon; slightly acid; (pH 6.4); clear wavy boundary. (4 to 14 inches thick)
Bt--22 to 29 inches; yellowish brown (10YR 5/4) clay loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky, slightly plastic; peds are hard, friable; enough mica in small flakes to give the soil mass a soaplike consistency when moist and crushed; thin wax-like patches on faces of peds and discontinuous wax-like coatings and fillings in root channels and pores; 5 percent pebbles; slightly acid (pH 6.4).
Cr--29 inches; weathered micaceous schist.
TYPE LOCATION: Jackson County, Colorado; approximately 600 feet south and 400 feet east of the N1/4 corner of Sec. 34. T. 32 N., R. 81 W.
RANGE IN CHARACTERISTICS:
Soil moisture: Udic moisture regime bordering on ustic.
Mean annual soil temperature: 39 to 41 degrees F
Mean summer soil temperature: 49 to 51 degrees
Depth to paralithic contact: 20 to 40 inches
Depth to argillic horizon: less than 24 inches
Base saturation: 60 to 100 percent
Particle-size control section (weighted average):
Rock fragments: 0 to 35 percent, dominantly gravel and cobble size
A horizon (if present):
Hue: 2.5Y through 7.5YR
Value: 4 through 6 dry, 2 or 3 moist
Chroma: 1 through 3
Reaction: moderately acid through slightly alkaline
E horizon:
Hue: 2.5Y through 7.5YR
Value: 5 through 8 dry, 4 through 7 moist
Chroma: 1 through 3
Reaction: strongly acid through slightly alkaline
E/B or B/E horizon(s):
Hue: 10YR through 7.5YR
Value: (E) 5 through 8 dry, 4 through 7 moist
Chroma: (E) 1 through 4
Value: (Bt) 4 through 7 dry, 3 through 6 moist
Chroma: (Bt) 1 through 6
Texture: sandy loam or loam
Reaction: strongly acid through slightly alkaline
Bt horizon:
Hue: 2.5Y through 7.5YR
Value: 4 through 7 dry, 3 through 6 moist
Chroma: 1 through 6
Texture: loam, clay loam, or sandy clay loam
Clay content: 18 to 35 percent
Silt content: 15 to 55 percent
Sand content: 15 to 60 percent with less than 35 percent fine or coarser sand
Reaction: strongly acid through slightly alkaline
C horizon (if present):
Hue: 2.5Y through 7.5YR, subhorizons redder than 7.5YR occur in some pedons.
Reaction: moderately acid through slightly alkaline
COMPETING SERIES: There are no competing series in this family.
GEOGRAPHIC SETTING:
Parent material: slope alluvium and colluvium over residuum derived from moderately thin noncalcareous medium to moderately fine textured very micaceous material weathered form micaceous bedrock
Landform: hills, ridges, and mountain slopes
Slopes: 2 to 60 percent
Elevation: 7,000 to 9,700 feet
Mean annual temperature: 36 to 41 degrees F
Mean summer temperature is 52 degrees
Mean annual precipitation: 17 to 24 inches
Precipitation pattern: Wettest months: March, April, May and June; driest months: September and October
Frost-free period: 30 to 75 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Perceton and Siebert soils. Siebert soils have an argillic horizon in which silicate clay is accumulating as lamellae.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; moderate permeability.
USE AND VEGETATION: These soils are used for livestock grazing or for limited timber production. Native vegetation is lodgepole pine, spruce, wild rose, fox barley, and elk sedge.
DISTRIBUTION AND EXTENT: Mountainous areas of Colorado. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Jackson County, Colorado, 1973.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: The zone from 22 to 29 inches. (Bt horizon)
Ochric epipedon: The zone from 2 to 4 inches. (A horizon)
Albic horizon: The zone from 4 to 14 inches. (E horizon)
Glossic horizon: The zone from 14 to 22 inches. (E/B horizon)
Argillic horizon: The zone from 22 to 29 inches. (Bt horizon)
Paralithic contact: The contact at 29 inches. (Cr)
The assignment of the paramicaceous mineralogy class is based on lab data from a similar soil in the area.
The mineralogy class was changed from paramicaceous to micaceous in 07/2010 by the National Soil Survey Center on request of the responsible MLRA regional office. The change was necessary based on the eleventh edition of the Keys to Soil Taxonomy, 2010.