LOCATION LABENZO IDEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Fluventic Haploxerolls
TYPICAL PEDON: Labenzo silt loam, cultivated, at an elevation of 4,830 feet on a nearly level slope. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 13 inches, grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, friable, slightly stick and slightly plastic; many very fine and fine roots; slight effervescence; moderately alkaline (pH 8.0); abrupt smooth boundary. (6 to 15 inches thick)
C1--13 to 17 inches; pale brown (10YR 6/3) silt loam, dark grayish brown (10YR 4/2) moist; moderate thin platy structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine and medium tubular pores; slight effervescence; moderately alkaline (pH 8.0); abrupt smooth boundary. (0 to 8 inches thick)
2C2--17 to 21 inches; discontinuous light brownish gray (10YR 6/2) loamy sand, dark grayish brown (10YR 4/2) moist; few fine faint dark brown (10YR 4/3) moist mottles; massive; soft, very friable; few very fine and fine roots; many very fine, fine, and medium tubular pores; slight effervescence; mildly alkaline (pH 7.8); abrupt wavy boundary. (0 to 6 inches thick)
3C3--21 to 24 inches, light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; few fine faint dark brown (10YR 4/3) moist mottles; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine, fine and medium tubular pores; slight effervescence; mildly alkaline (pH 7.8); abrupt wavy boundary. (0 to 6 inches thick)
3C4--24 to 28 inches; mixture of dark gray (10YR 4/1) and light brownish gray (10YR 6/2) silt loam, very dark brown (10YR 2/2) and dark grayish brown (10YR 4/2) moist; few faint dark yellowish brown (10YR 4/4) moist mottles; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine and fine tubular pores; slight effervescence; moderately alkaline (pH 8.0); abrupt wavy boundary. (0 to 8 inches thick)
4C5--28 to 34 inches; light brownish gray (10YR 6/2) lenses of 80 percent silt loam, 20 percent loamy sand, dark grayish brown (10YR 4/2) moist; few medium distinct dark yellowish brown (10YR 4/4) moist mottles; massive; soft, very friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine and fine tubular pores; slight effervescence; moderately alkaline (pH 8.0); abrupt wavy boundary. (0 to 10 inches thick)
5C6--34 to 45 inches; light brownish gray (10YR 6/2) very gravelly sand, dark grayish brown (10YR 4/2) moist; loose; few very fine and fine roots; slight effervescence; moderately alkaline (pH 8.0).
TYPE LOCATION: Jefferson County, Idaho; about 3 1/2 miles north of Rigby; 120 feet north and 250 feet east of the southwest corner of section 30, T.5N., R.39E.
RANGE IN CHARACTERISTICS:
Organic carbon - decreases irregularly with depth to 0.3 percent or less within 50 inches of the surface
Soil moisture - usually moist but at 4 to 12 inches it is dry for 60 to 90 consecutive days in summer
Particle-size control section - upper part 18 to 25 percent clay Depth to sand and gravel - 24 to 36 inches
Summer soil temperature - 61 to 63 degrees F.
Average annual soil temperature - 43 to 47 degrees F.
A horizon
Value - 4 or 5 dry, 3 or 4 moist
Chroma - 1 through 3 dry or moist
Reaction - mildly or moderately alkaline
Structure - granular, platy or subangular blocky
C horizons
Value - 4 through 7 dry, 2 through 4 moist
Chroma - 1 through 3 dry or moist
Other- one or more buried horizons occur in some pedons
COMPETING SERIES: There are no other soils in the same family. The closely related Blackfoot soils are somewhat poorly drained and are more than 40 inches deep to sand and gravel.
GEOGRAPHIC SETTING: Labenzo soils are on river terraces at elevations of 4,700 to 5,400 feet. They formed in mixed alluvium. Slopes are 0 to 1 percent. Frost-free season is 80 to 115 days. Average annual precipitation is 8 to 13 inches, including 1 to 3 feet of snow. Average annual temperature is 41 to 45 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Blackfoot and the Harston, Heiseton, and Wardboro soils. Harston and the Heiseton soils have a coarse-loamy control section, and the Heiseton soils are more than 40 inches deep to sand and gravel. Wardboro soils are 10 to 20 inches deep to sand and gravel. These soils are on terraces.
DRAINAGE AND PERMEABILITY: Moderately well drained; very slow runoff; moderate permeability in the upper part and very rapid below.
USE AND VEGETATION: Used for production of alfalfa, hay, small grains, pasture, and some potatoes. Natural vegetation is mainly perennial grasses with some willows and big sagebrush.
DISTRIBUTION AND EXTENT: Southeastern Idaho. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Jefferson County, Idaho, 1975.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from 0 to 13 inches (Ap horizon)
Particle-size control section - the zone from 10 to 40 inches
Other- the soil appears to have been formed under somewhat poorly drained condition but is presently moderately well drained because artificial drainage has been applied and drainage channels lowered which have permanently lowered the water table.