LOCATION LANOAK IDEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Pachic Haploxerolls
TYPICAL PEDON: Lanoak silt loam - cultivated. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 7 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; moderate very fine and fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine irregular and few very fine tubular pores; slightly acid (pH 6.5); abrupt smooth boundary. (0 to 10 inches thick)
A--7 to 16 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; few 1/2 inch splotches of grayish brown (10YR 5/2); weak fine subangular blocky structure parting to moderate fine and medium granular; slightly hard, very friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and fine tubular pores; few uncoated silt grains; slightly acid (pH 6.4); gradual wavy boundary. (6 to 12 inches thick)
AB--16 to 22 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; weak medium prismatic structure parting to moderate medium and fine subangular blocky and fine granular; hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine and fine tubular pores; few uncoated silt grains; few darker krotovinas 3 inches across; neutral (pH 6.6); gradual wavy boundary. (0 to 10 inches thick)
Bt1--22 to 29 inches; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; weak medium prismatic structure parting to moderate fine subangular blocky; hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine tubular pores; many uncoated silt grains on vertical faces of peds; common faint clay films on faces of peds and many in some pores; few darker krotovinas 3 inches across; neutral (pH 6.7); gradual smooth boundary. (5 to 14 inches thick)
Bt2--29 to 38 inches; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to moderate fine subangular blocky; very hard, friable, slightly sticky and moderately plastic; few very fine and fine roots; many very fine and few fine tubular pores; many uncoated silt grains mainly on vertical faces of peds; common faint clay films on faces of peds and in pores; few dark krotovinas 3 inches across; neutral (pH 6.7); clear smooth boundary. (8 to 10 inches thick)
Bt3--38 to 48 inches; brown (10YR 5/3), pale brown (10YR 6/3) crushed silt loam, brown (10YR 4/3) moist; weak medium prismatic structure parting to moderate fine and medium subangular blocky; very hard, friable, slightly sticky and slightly plastic; few very fine roots; many very fine and few fine tubular pores; few uncoated silt grains on vertical faces of peds; common faint clay films on faces of peds and in pores; one thin horizontal wavy yellowish brown (10YR 5/4) more clayey lamellae; few dark krotovinas 3 inches across; neutral (pH 6.7); clear smooth boundary. (0 to 15 inches thick)
Bkt--48 to 57 inches; pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; weak fine and medium subangular blocky structure; very hard, friable, slightly sticky and slightly plastic; few very fine roots; many very fine and few fine tubular pores; few thin clay films on faces of peds and in channels; few dark krotovinas 3 inches across; noncalcareous except some pockets of moderately calcareous material with common lime veins and spots; slightly alkaline (pH 7.4); gradual wavy boundary. (0 to 15 inches thick)
Bk1--57 to 67 inches; light gray (10YR 7/2) silt loam, brown (10YR 5/3) moist; massive; hard, friable, slightly sticky, slightly plastic; few very fine roots; many very fine tubular pores; strongly calcareous and common very fine spots of lime; slightly alkaline (pH 7.7); gradual irregular boundary. (5 to 15 inches thick)
Bk2--67 to 115 inches; light gray (10YR 7/2) silt loam, brown (10YR 5/3) moist; few fine distinct light yellowish brown (10YR 6/4) and pale yellow (2.5Y 7/3) redox concentrations, yellowish brown (10YR 5/4) moist; common very dark gray (10YR 3/1) soft manganese-iron concretions 1mm in diameter; massive; hard, friable, slightly sticky and slightly plastic; few very fine roots; few very fine tubular pores; strongly calcareous and very few fine spots of lime; slightly alkaline (pH 7.7).
TYPE LOCATION: Bannock County, Idaho; 125 feet south of bridge and 120 feet north of blazed tree in aspen grove; 4 percent northerly slope at 5,600 feet elevation; northeast 1/4, southwest 1/4, southwest 1/4, northeast 1/4 of section. 4, T.6S., R.36E.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon - 20 to 40 inches
Particle-size control section - 18 to 27 percent clay
Mean annual soil temperature - 42 to 47 degrees F.
Depth to carbonates - 43 to 60 inches
A horizon
Value, dry - 3 to 5
Value, moist - 1 to 3
Chroma, dry or moist - 1 through 3
Reaction - slightly acid to slightly alkaline
Bt horizon
Value, dry - 4 to 6
Value, moist - 2 to 4
Chroma, dry or moist - 2 or 3
Reaction - neutral or slightly alkaline
Btk and Bk horizons
Value, dry - 6 or 7
Value, moist - 4 or 5
Chroma, dry or moist - 2 or 3
Reaction - neutral to moderately alkaline
Effervescence - slight to violent
COMPETING SERIES: This is the Ninepipe series. Ninepipe are effervescent throughout the profile and have 5 to 10 percent calcium carbonate in the subsoil and substratum.
GEOGRAPHIC SETTING: Lanoak soils are on foothills, ridges, fan terraces, and mountain slopes. Slopes are 0 to 50 percent. They formed in loess and silty alluvium derived from loess. The mean annual precipitation is 14 to 18 inches and the mean annual temperature is 39 to 45 degrees F. Frost-free period is 70 to 100 days. Elevation is 4,500 to 6,600 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Camelback, Hades, Hondoho, Rexburg, Ricrest, Ridgecrest, and the competing Bancroft series. Camelback soils have argillic horizons and are loamy-skeletal. Hades soils have argillic horizons and are fine-loamy. Hondoho soils are loamy-skeletal and have calcic horizons. Rexburg soils are coarse-silty, have calcic horizons, and lack pachic epipedons. Ricrest soils are fine-loamy and have calcic horizons. Ridgecrest soils are moderately deep to bedrock and are loamy-skeletal. Camelback, Ricrest, and Ridgecrest soils are on mountain slopes above the Lanoak soils. Hades and Hondoho soils are on terrace breaks. Rexburg and Bancroft soils are on linear south and west-facing slopes where associated with Lanoak soils.
DRAINAGE AND PERMEABILITY: Well drained; runoff is slow through very rapid; permeability is moderate.
USE AND VEGETATION: This Lanoak soil is used mainly as non-irrigated cropland and rangeland. The potential natural vegetation is mountain big sagebrush and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: Southeastern, Idaho. This series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Bannock County, Idaho, 1972.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the soil surface to 38 inches
Cambic horizon - the zone from 38 to 115 inches
Particle-size control section - the zone from 10 to 40 inches