LOCATION SIMEROI IDEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, carbonatic, frigid Xeric Haplocalcids
TYPICAL PEDON: Simeroi gravelly loam - on a southwest-facing slope of 8 percent in rangeland at 7,000 feet elevation. (Colors are for dry soil unless otherwise stated. When described on September 2, 1981, the upper 40 inches of the profile was dry and the 40 to 60 inch area of the profile was moist.)
A1--0 to 3 inches; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; weak very fine and fine subangular blocky structure parting to weak very fine and fine granular; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, common fine and few medium roots; many very fine and fine irregular pores; 20 percent gravel; slightly alkaline (pH 7.6); abrupt wavy boundary. (0 to 5 inches thick)
A2--3 to 7 inches; pale brown (10YR 6/3) very gravelly loam, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, common fine and few medium roots; many very fine irregular pores; 40 percent gravel; strongly effervescent; slightly alkaline (pH 7.8); clear wavy boundary. (2 to 10 inches thick)
Bk--7 to 10 inches; light yellowish brown (10YR 6/4) very gravelly loam, brown (10YR 4/3) moist; weak very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine and few medium and coarse roots; many very fine and fine irregular pores; 30 percent gravel, 5 percent cobbles; strongly effervescent; moderately alkaline (pH 8.0); clear wavy boundary. (0 to 5 inches thick)
Bkq1--10 to 16 inches; very pale brown (10YR 7/3) very gravelly loam, brown (10YR 5/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; common very fine and few fine roots; few very fine tubular and irregular pores; 40 percent gravel, 5 percent cobbles; lime and silica pendants 1 to 4 mm thick on undersides of rock fragments; violently effervescent, (65 percent calcium carbonate equivalent); moderately alkaline (pH 8.2); clear wavy boundary. (5 to 10 inches thick)
Bkq2--16 to 23 inches; light gray (10YR 7/2) very gravelly sandy loam, brown (10YR 5/3) moist; massive, 20 percent hard and 80 percent slightly hard, 20 percent firm and 80 percent friable, slightly sticky and slightly plastic; few very fine roots; few very fine irregular pores; 45 percent gravel, 5 percent cobbles; lime and silica coatings 1 to 4 mm thick on undersides and sides of rock fragments; violently effervescent, (65 percent calcium carbonate equivalent); moderately alkaline (pH 8.2); clear wavy boundary. (6 to 10 inches thick)
Bkq3--23 to 54 inches; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine roots; many very fine and common fine irregular pores; 45 percent gravel, 10 percent cobbles; lime and silica coatings 1 to 4 mm thick on undersides of rock fragments; violently effervescent, (65 percent calcium carbonate equivalent); moderately alkaline (pH 8.4); clear wavy boundary. (10 to 35 inches thick)
2Bkq4--54 to 60 inches; pale brown (10YR 6/3) extremely gravelly loamy coarse sand, brown (10YR 5/3) moist; single grain; loose; few very fine roots; few very fine and fine irregular pores; 55 percent gravel, 5 percent cobbles; lime and silica coatings up to 1 mm thick on undersides of rock fragments; violently effervescent; strongly alkaline (pH 8.6).
TYPE LOCATION: Lemhi County, Idaho; about 36 miles southeast of Leadore, Idaho; about 2,300 feet north and 600 feet west of the southeast corner of sec. 19, T. 11 N., R. 30 E. Latitude - 44 degrees, 15 minutes, 57 seconds North; Longitude - 112 degrees, 54 minutes, 57 seconds West.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 39 to 46 degrees F.
Depth to calcic horizon - 2 to 15 inches
Reaction - slightly alkaline to strongly alkaline
Particle-size control section
Clay - 4 to 20 percent
Rock fragments - 40 to 85 percent
A horizon
Hue - 2.5Y or 10YR
Value - 5 to 7 dry, 3 to 5 moist
Chroma - 2 to 4 dry or moist
Calcium carbonate equivalent - 5 to 10 percent
Bk and Bkq horizons
Hue - 2.5Y or 10YR
Value - 5 to 8 dry, 4 to 7 moist
Chroma - 2 to 4 dry and 2 through 6 moist
Texture - GRV-L, GRV-SL, GRV-COSL, GRX-L, GRX-COSL, GRX-FSL, GRX-SL
Calcium carbonate equivalent - 30 to 70 percent
2Bkq horizon (when present)
Texture - GRX-COS, GRX-LCOS, GRV-L, GRX-L, or GRV-LCOS
COMPETING SERIES: These are the Horseridge (T) and Overland series. Overland soils are 20 to 60 inches to bedrock. Horseridge soils lack the accumulation of silica; recommend correlation to Simeroi series.
GEOGRAPHIC SETTING: Simeroi soils are on outwash fans, fan terraces, fan remnants, and foothills at elevations of 4,500 to 8,800 feet. Slopes range from 1 to 60 percent. The soils formed in alluvium derived dominantly from limestone. There is a minor component of loess in the upper part of some pedons. Mean annual air temperature ranges from 38 to 44 degrees F. Mean summer temperature is 60 to 63 degrees F. The mean annual precipitation ranges from 8 to 12 inches. Frost-free period is 50 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Custco, Dacont, Dawtonia, Leatherman, Mogg, Ringle, and Whitecloud soils. Custco, Dacore, and Dawtonia soils are on mountains and foothills and have argillic horizons. Leatherman soils are on fan terraces and have duripans. Mogg soils are on mountains and are shallow to bedrock. Ringle and Whitecloud soils are on fan terraces and have sandy-skeletal control sections.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; permeability is moderate.
USE AND VEGETATION: Rangeland. Small acreages are used for the irrigated production of grass and legumes for hay and pasture. Vegetation is mainly Wyoming big sagebrush black sagebrush, low sagebrush and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: East-central Idaho. These soils are moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Lemhi County, Idaho, 1999.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from 0 to 7 inches
Calcic horizon - The zone from 7 to 60 inches
The particle-size control section is the zone from 10 to 40 inches (Bkq1, Bkq2, and part of the Bkq3 horizons).