LOCATION LAGO IDEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Aquic Calcixerolls
TYPICAL PEDON: Lago silt loam, nonirrigated cropland; on a 0.5 percent slope at 4,910 feet elevation in grass hay. When described on July 9, 1987, the soil was wet below 16 inches. (Color is for dry soil unless otherwise noted.)
A--0 to 9 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure parting to moderate very fine subangular blocky; slightly hard, friable, moderately sticky and moderately plastic; many very fine and few fine roots; common very fine tubular and irregular pores; common snail shells and shell fragments; strongly effervescent; strongly alkaline (pH 8.8); gradual smooth boundary. (8 to 19 inches thick)
Bk--9 to 16 inches; grayish brown (10YR 5/2) silt loam, dark grayish brown (10YR 4/2) moist; strong very fine subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; many very fine roots; common fine tubular pores; strongly effervescent; common fine irregularly shaped carbonate masses and filaments; common snail shells and shell fragments; strongly alkaline (pH 8.8); clear smooth boundary. (5 to 10 inches thick)
Bkg1--16 to 27 inches; gray (10YR 5/1) silt loam, very dark gray (10YR 3/1) moist; weak medium prismatic structure parting to weak very fine subangular blocky; hard, firm, moderately sticky and moderately plastic; many very fine roots; many very fine tubular pores; common snail shells and shell fragments; strongly effervescent; disseminated carbonates; strongly alkaline (pH 8.8); gradual smooth boundary. (6 to 12 inches thick)
Bkg2--27 to 35 inches; light gray (10YR 7/2) silt loam, grayish brown (10YR 5/2) moist; moderate very fine subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine roots; many very fine tubular pores; common fine distinct dark yellowish brown (10YR 4/4) and common fine prominent yellowish brown (10YR 5/6) moist masses of iron accumulation; common snail shells and shell fragments; strongly effervescent; disseminated carbonates; strongly alkaline (pH 8.8); clear smooth boundary. (5 to 9 inches thick)
Bkg3--35 to 45 inches; light gray (10YR 7/2) silt loam, light brownish gray (10YR 6/2) moist; massive; very hard, firm, moderately sticky and moderately plastic; few very fine roots; common snail shells and shell fragments; strongly effervescent; disseminated carbonates; strongly alkaline (pH 8.6); clear smooth boundary. (5 to 10 inches thick)
Cg--45 to 60 inches; light gray (10YR 7/2) sandy loam, light brownish gray (10YR 6/2) moist; massive; very hard, firm; few very fine roots; many snail shells and shell fragments; strongly effervescent; disseminated carbonates; moderately alkaline (pH 8.4).
TYPE LOCATION: Franklin County, Idaho; about 0.5 mile northwest of Thatcher, about 1,375 feet east and 260 feet south of the northwest corner of section 1, T. 12 S, R. 40 E.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon - 8 to 19 inches
Depth to secondary lime - 8 to 19 inches
Depth to redox concentrations - 20 to 30 inches
Depth to seasonal high water table - 20 to 30 inches
Average annual soil temperature - 42 to 45 degrees F.
Particle-size control section
Clay content - averages 22 to 35 percent
Present in some pedons
O horizon
A horizon
Hue - 10YR, 2.5Y or 5Y
Value - 3 through 5 dry, 2 or 3 moist
Chroma - 0 through 2 dry or moist
Effervescence - slight or strong
Reaction - moderately or strongly alkaline
Bk horizon
Hue - 10YR, 2.5Y or 5Y
Value - 6 or 7 dry, 4 through 6 moist
Chroma - 0 through 2 dry or moist
Texture - SIL or SICL
Effervescence - strong or violent
Reaction - moderately or strongly alkaline
Bkg1 and Bkg2 horizons
Hue - 10YR, 2.5Y or 5Y
Value - 5 through 7 dry, 3 through 5 moist
Chroma - 1 or 2 dry or moist
Texture - SIL or SICL
Effervescence - strong or violent
Reaction - moderately or strongly alkaline
Bkg3 horizon
Hue - 10YR, 2.5Y or 5Y
Value - 5 through 7 dry, 4 through 6 moist
Chroma - 0 or 2 dry or moist
Texture - SIL or SICL
Effervescence - strong of violent
Reaction - moderately or strongly alkaline
Cg horizon (Absent in some pedons)
Hue - 10YR, 2.5Y or 5Y
Value - 6 or 7 dry or moist
Chroma - 1 or 2 dry or moist
Texture - SIL or SL
Effervescence - strong or violent
Reaction - moderately through strongly alkaline
COMPETING SERIES: This is the Arco series. Arco soils are in an 8 to 12 inch precipitation zone.
GEOGRAPHIC SETTING: Lago soils are on flood plains, drainageways, and flood plain steps. Slopes range from 0 to 3 percent. Elevations range from 4,300 to 6,500 feet. These soils formed in silty alluvium. The average annual precipitation ranges from 12 to 18 inches, the average annual air temperature is 39 to 43 degrees F and the frost free season is 70 to 110 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bear Lake, Iphil, and Rexburg soils. Bear Lake soils have an aquic moisture regime. Iphil and Rexburg soils have a coarse-silty textural control section. Bear Lake soils are on smooth to concave slopes lower on the landscape than Lago. Iphil and Rexburg soils are on loess and silty alluvium covered fan terraces above Lago soils.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow runoff; moderately slow permeability. Lago soils are rarely or occasionally flooded for brief periods from April through June in most years, and at other times following periods of intense rainfall.
USE AND VEGETATION: Lago soils are used for non-irrigated cropland and rangeland. Typical crops consist of grass hay. The current vegetation is annual bluegrass and clovers.
DISTRIBUTION AND EXTENT: Southeastern Idaho. This series is inextensive. MLRAs 13 and 28A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Franklin County, Idaho, 1997.
REMARKS: Buried horizons with mollic colors are common in this soil. The buried layers are separated from the overlying mollic epipedon by a lighter colored layer. The buried horizons do not contribute to the thickness of the mollic.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the surface to 9 inches (A horizon)
Calcic horizon - the zone from 9 to 27 inches (Bk and Bkg1 horizons)
Particle-size control section - the zone from 10 to 40 inches (part of the Bk, the Bkg1, the Bkg2, and part of the Bkg3 horizons)