LOCATION STAN IDEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Aridic Calcixerolls
TYPICAL PEDON: Stan fine sandy loam, cultivated. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 8 inches; grayish brown (10YR 5/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; very weak very fine granular structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine tubular pores; slightly effervescent; slightly alkaline (pH 7.4); gradual smooth boundary. (0 to 8 inches thick)
A--8 to 16 inches; brown (10YR 5/3) fine sandy loam, very dark grayish brown (10YR 3/2) moist; very weak medium subangular blocky structure; hard, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine roots; many very fine and fine tubular pores; slightly effervescent; slightly alkaline (pH 7.4); gradual smooth boundary. (3 to 10 inches thick)
Bw--16 to 29 inches; pale brown (10YR 6/3) fine sandy loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; hard, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine tubular pores; slightly effervescent; slightly alkaline (pH 7.4); clear wavy boundary. (3 to 14 inches thick)
Bk1--29 to 38 inches; light gray (10YR 7/2) fine sandy loam, dark grayish brown (10YR 4/2) moist; massive; hard, friable, nonsticky and nonplastic; common very fine and fine tubular pores; about 5 percent hard nodules or cicada krotovinas; strongly effervescent, common fine veins, spots, and splotches of calcium carbonate; slightly alkaline (pH 7.8); gradual wavy boundary. (6 to 15 inches thick)
Bk2--38 to 50 inches; light gray (10YR 7/2) fine sandy loam, grayish brown (10YR 5/2) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common very fine roots; many very fine and fine tubular pores; strongly effervescent, common veins and coatings of calcium carbonate; slightly alkaline (pH 7.7); clear wavy boundary. (0 to 15 inches thick)
2Bk3--50 to 60 inches; light gray (10YR 7/2) very gravelly sandy loam, grayish brown (10YR 5/2) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots; many very fine irregular pores; slightly effervescent, gravel fragments coated with calcium carbonate on lower side and partially coated on upper side; slightly alkaline (pH 7.8).
TYPE LOCATION: Bingham County, Idaho; about 4 miles north of Blackfoot; 500 feet west and 150 feet south of the center of section 15, T.2S., R.35E.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon - 10 to 16 inches
Depth to calcic horizon - 12 to 30 inches
Depth to discontinuity - 40 to 60 inches
Mean annual soil temperature - 41 to 47 degrees F.
Soil moisture - dry for about 60 to 80 consecutive days in mid and late summer
Reaction - slightly or moderately alkaline throughout
Particle-size control section
Noncarbonate clay content - 8 to 16 percent
Rock fragments - 0 to 15 percent (average)
A horizons
Hue - 10YR or 2.5Y
Chroma - 2 or 3
Structure - weak platy or weak or very weak granular
Bw horizon
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 2 or 3
Texture - FSL, SL, L
Structure - weak granular or weak subangular blocky
Carbonates - slightly effervescent
Bk horizons
Hue - 10YR or 2.5Y
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 2 or 3
Texture - FSL, SL, L, GR-FSL, GR-SL
Structure - massive or weak subangular blocky
Calcium carbonate equivalent - 15 to 25 percent
2Bk horizon
Hue - 10YR or 2.5Y
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 2 or 3
Texture - GRV-SL, GRV-LS, GRV-COS
COMPETING SERIES: This is the Beartrap series. Beartrap soils have bedrock at 40 to 60 inches.
GEOGRAPHIC SETTING: The soils are on alluvial fans at elevations of 4,200 to 5,500 feet. Slopes range from 0 to 4 percent. The soil formed in alluvium that is dominantly from quartzite and sedimentary rock sources, but contains some rhylitic, basaltic, and granitic materials. In places, the upper part may be loess. The climate is semiarid with dry summers. The mean annual precipitation is 10 to 13 inches including 2 to 5 feet of snowfall. The frost free season is 80 to 125 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bannock, Bock and Sasser soils. Bannock and Sasser soils have sand and gravel at a depth of 20 to 40 inches. Bock soils are medium textured and are not calcareous to the surface. All of these soils are on similar positions.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderately rapid permeability.
USE AND VEGETATION: Mostly cultivated under irrigation for hay, pasture, potatoes, and small grains. The principal native plants are big sagebrush, bluebunch wheatgrass, Sandberg bluegrass, cheatgrass, and squirreltail.
DISTRIBUTION AND EXTENT: Moderately extensive in the Upper Snake River Valley of Idaho.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Bingham County, Idaho, 1972.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the surface to 16 inches (Ap and A horizons)
Cambic horizon - the zone from 16 to 29 inches (Bw horizon)
Calcic horizon - the zone from 29 to 60 inches (Bk1, Bk2, and 2Bk3 horizons)
Aridic subgroup - Aridic moisture regime bordering on xeric.
Particle-size control section - The zone from 10 to 40 inches (part of the A and the Bw, Bk1 and part of the Bk2 horizons).