LOCATION SUDPEAK IDEstablished Series
TAXONOMIC CLASS: Fine, smectitic Vertic Argicryolls
TYPICAL PEDON: Sudpeak loam, in rangeland on a 3 percent east facing slope at an elevation of 5000 feet. (Colors are for dry soil unless otherwise noted.)
A1--0 to 11 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; weak medium and fine subangular blocky structure parting to moderate medium and fine granular; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine roots; common very fine vesicular pores; many thin clay films bridging mineral grains; slightly acid (pH 6.2); gradual wavy boundary. (5 to 15 inches thick)
A2--11 to 16 inches; dark grayish brown (10YR 4/2) loam, dark brown (7.5YR 3/3) moist; moderate medium subangular blocky structure parting to moderate fine and medium granular; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine vesicular and common very fine tubular pores; continuous thin clay films bridging mineral grains; neutral (pH 6.6); clear wavy boundary. (3 to 8 inches thick)
AB--16 to 22 inches; dark grayish brown (10YR 4/2) clay loam, dark brown (7.5YR 3/3) moist; moderate medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and moderately plastic; few very fine roots; common very fine and few fine vesicular and few fine tubular pores; continuous distinct clay films lining pores and bridging mineral grains; neutral (pH 6.6); clear smooth boundary. (6 to 18 inches thick)
Bt1--22 to 36 inches; brown (10YR 5/3) silty clay loam, dark brown (7.5YR 3/3) moist; strong medium and coarse subangular blocky structure;hard, firm, moderately sticky and moderately plastic; many very fine vesicular and few fine tubular pores; continuous prominent clay films lining pores and on faces of peds; neutral (pH 6.6); abrupt smooth boundary. (14 to 20 inches thick)
Bt2--36 to 41 inches; brown (10YR 5/3) silty clay loam, dark brown (7.5YR 3/3) moist; common fine distinct brownish yellow (10YR 6/6) redox concentrations, dark yellowish brown (10YR 3/6) moist; strong medium and coarse subangular blocky structure; hard, firm, moderately sticky and moderately plastic; many very fine vesicular and few fine tubular pores; continuous prominent clay films lining pores and on faces of peds; slightly acid (pH 6.4); abrupt smooth boundary. (5 to 12 inches thick)
Bg--41 to 60 inches; very pale brown (10YR 7/3) clay loam, grayish brown (10YR 5/2) moist; many medium prominent brownish yellow (10YR 6/6) redox concentrations, dark yellowish brown (10YR 4/6) moist; strong medium and coarse subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine vesicular and few fine tubular pores; slightly acid (pH 6.4).
TYPE LOCATION: Valley County, Idaho; approximately 3 miles south and 3 miles west of McCall, about 1,500 feet east and 1,540 feet north of the southwest corner of Section 26, T.18N., R. 2E.
RANGE IN CHARACTERISTICS:
Clay content of control section - 35 to 45 percent
Coarse fragments in the control section - 0 to 30 percent Reaction of profile - neutral or slightly acid
Depth to high water table - 3 to 6 feet
A horizon
Value - 3 to 5 dry, 2 or 3 moist
Chroma - 1 to 3 dry or moist
Bt horizon
Hue - 10YR or 7.5YR
Value - 4 through 6 dry, 2 through 5 moist
Chroma - 2 through 6 dry, 2 through 4 moist
Textures - CL, SICL, C, GR-C, GR-CL
Bg horizon
Value - 5 through 7 dry, 3 through 5 moist
Chroma - 2 through 4 dry or moist
Textures - CL, C, SICL
COMPETING SERIES: These are the Beaverdam, Buckskin, Cimarron, Cucharas, Gourley, Heathcoat, Savar, Slights (T), Sudduth, Toponce, Wetopa, and Youman series. The Beaverdam, Buckskin, Cimarron, Cucharas, Gourley, Heathcoat, and Youman soils have mollic epipedons less than 16 inches thick. In addition, Cucharas soils are moderately deep to a paralithic contact, and Gourley and Heathcoat soils have horizons of secondary carbonate accumulation. The Savar soils have horizons of secondary carbonate accumulation. Slights soils are moderately acid in the Bt horizon and lack a water table. Sudduth soils have a lithologic discontinuity. Toponce soils have a solum thickness of 60 inches or more and lack a water table. Wetopa soils lack a water table and redox features above 40 inches.
GEOGRAPHIC SETTING: Sudpeak soils are on alluvial and colluvial fan terraces and terraces of small mountain streams and have slopes of 0 to 20 percent. They have formed in alluvium and colluvium from basalt and other igneous rocks. Elevation is 3,800 to 6,600 feet. Average annual temperature is 36 to 46 degrees F. Average annual precipitation is 22 to 26 inches. Frost free season is 40 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Demast, Shotgun (T) and Tica soils. Demast soils have less than 35 percent clay in the control section and are on foothills and mountain slopes. Shotgun soils are less than 40 inches deep to bedrock and are on basalt plains. Tica soils are less than 20 inches to bedrock and are on mountain slopes and foothills.
DRAINAGE AND PERMEABILITY: Moderately well drained. Slow to medium runoff. Permeability is slow.
USE AND VEGETATION: Rangeland, wildlife habitat, recreation and hay and pasture. The potential native vegetation is slender wheatgrass, bluebunch wheatgrass, Idaho fescue, tufted hairgrass, basin wildrye, Kentucky bluegrass and sedge.
DISTRIBUTION AND EXTENT: Central and southeastern Idaho. These soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Fremont County, Idaho, 1989.
REMARKS: Diagnostic properties recognized in this profile are:
Mollic epipedon - From 0 to 41 inches. (A1 through Bt2 horizons).
Argillic horizon - from 22 to 41 inches (Bt1 and Bt2 horizons).
Particle-size control section - From 22 to 41 inches (Bt1 & part of the Bt2 horizons).