LOCATION LONIGAN IDEstablished Series
TAXONOMIC CLASS: Ashy-skeletal, glassy, frigid Vitrandic Haploxerolls
TYPICAL PEDON: Lonigan cobbly silt loam, rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 3 inches; dark grayish brown (10YR 4/2) cobbly silt loam, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots, and common medium and coarse roots; many very fine irregular pores; about 15 percent gravel and 15 percent cobbles; slightly alkaline (pH 7.5); abrupt smooth boundary. (2 to 5 inches thick)
A2--3 to 7 inches; grayish brown (10YR 5/2) cobbly silt loam, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots, and common medium and coarse roots; many very fine irregular pores; about 15 percent gravel and 15 percent cobbles; slightly alkaline (pH 7.6); clear smooth boundary. (3 to 7 inches thick)
Bw--7 to 12 inches; brown (10YR 5/3) very cobbly silt loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots, and common medium and coarse roots; many very fine irregular pores; about 20 percent gravel and 25 percent cobbles; slightly effervescent; slightly alkaline (pH 7.6); clear wavy boundary. (3 to 8 inches thick)
Bk1--12 to 19 inches; pale brown (10YR 6/3) very cobbly loam, brown (10YR 4/3) moist; massive; soft, very friable, slightly sticky and slightly plastic; many very fine roots, common fine and medium roots, and few coarse roots; many very fine irregular pores; about 25 percent gravel and 30 percent cobbles; violently effervescent; slightly alkaline (pH 7.5); clear wavy boundary. (4 to 10 inches thick)
Bk2--19 to 27 inches; very pale brown (10YR 8/2) extremely cobbly loam, light yellowish brown (10YR 6/4) moist; massive; soft, very friable, nonsticky and slightly plastic; common very fine, fine and medium roots, and few coarse roots; many very fine irregular pores; about 30 percent gravel and 35 percent cobbles; violently effervescent; moderately alkaline (pH 8.1); abrupt irregular boundary. (5 to 15 inches thick)
Cr--27 inches; very highly fractured and weathered consolidated volcanic ash.
TYPE LOCATION: Bannock County, Idaho; about 1.5 miles southwest of Hawkin's Reservoir, about 220 feet south and 1,100 feet east of the northwest corner, sec. 3, T. 11 S., R. 35 E.
RANGE IN CHARACTERISTICS:
Depth to lime - 0 to 18 inches
Depth to Calcic horizon - 8 to 20 inches
Coarse fragments - dominantly consolidated ash, mixed with calcareous tuff, calcite, and cinders
Average annual soil temperature - 44 to 47 degrees F
Depth to paralithic contact - 20 to 40 inches
Particle-size Control Section:
Coarse fragments - 35 to 70 percent
Volcanic glass percentage of the .02 - 2.0 mm fraction - 50 to 80 percent
A horizon
Value - 3 through 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Reaction - neutral through moderately alkaline
Bw horizon
Hue - 2.5Y or 10YR
Value - 3 through 7 dry, 2 through 6 moist
Chroma - 2 or 3 dry or moist
Texture - GRV-L, GRV-SIL, CBV-SIL
Reaction - mildly or moderately alkaline
Bk horizon
Hue - 10YR or 2.5Y
Value - 6 through 8 dry, 4 through 7 moist
Chroma - 0 through 4 dry or moist
Texture - GRV-L, FLV-L, CBV-L, CBX-L, GRV-SIL, FLX-L, CHV-L
Calcium carbonate equivalent - 15 to 40 percent
Reaction - mildly or moderately alkaline
COMPETING SERIES: This is the Stines series. Stines soils are more than 40 inches deep.
GEOGRAPHIC SETTING: Lonigan soils are on foothills, mountain sideslopes, and toeslopes. Elevation range from 4,600 to 6,500 feet. Slopes are 5 to 80 percent. This soil formed in volcanic ash and calcareous tuff with a component of loess. Average annual precipitation is 14 to 18 inches, most of this coming during the winter in the form of snow. Average annual temperature is 42 to 45 degrees F. Average annual summer temperature is 57 to 64 degrees F. Frost-free period is about 70 to 95 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bluehill, Bradshaw, Cedarhill, Coalbank, and Manila soils. Bluehill soils are mesic and have less than 35 percent coarse fragments in the control section. Bradshaw, Cedarhill, and Manila soils are not ashy. Coalbank soils are greater than 40 inches deep to paralithic material and have less than 35 percent coarse fragments in the control section. Bradshaw, Cedarhill, and Manila soils are in areas of non-ashy parent material. Bluehill soils are on south-facing slopes. Coalbank soils are in concave positions on north and east-facing slopes.
DRAINAGE AND PERMEABILITY: Well drained; medium to very rapid runoff; moderately rapid permeability.
USE AND VEGETATION: Used mainly for rangeland. Vegetation is mainly mountain big sagebrush, antelope bitterbrush, bluebunch wheatgrass, and snowberry.
DISTRIBUTION AND EXTENT: Inextensive in southeastern Idaho.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Bannock County, Idaho, 1983.
REMARKS: This revision changes the classification from Mollic Vitrandepts to Vitrandic Haploxerolls.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the surface to 12 inches (the A1, A2, and Bw horizons)
Calcic horizon - The zone from 12 to 27 inches (the Bk1 and Bk2 horizons)
Particle-size control section - The zone from 10 inches to the paralithic contact at 27 inches (part of the Bw, the Bk1, and the Bk2 horizons)