LOCATION DRANYON ID+CO UT WYEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive Pachic Argicryolls
TYPICAL PEDON: Dranyon stony loam - aspen. (Colors are for dry soil unless otherwise stated.)
Oi--0 to 1 inch; slightly decomposed leaves and twigs primarily from aspen and the understory; strongly acid (pH 5.2); abrupt wavy boundary. (0 to 1 inch thick)
Oe--1 to 1.5 inch; moderately decomposed very dark brown (10YR 2/2) matted leaves and twigs, black (10YR 2/1) moist; abrupt wavy boundary. (0 to 1 inch thick)
Oa--1.5 to 2 inches; highly decomposed very dark brown (10YR 2/2) organic matter; common fine roots; abrupt wavy boundary. (0 to 1 inch thick)
A--2 to 5 inches; dark grayish brown (10YR 4/2) stony loam, very dark brown (7.5YR 2/2) moist; weak very fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; common fine and few medium and coarse roots; many fine irregular and tubular pores; few uncoated silt grains; 10 percent gravel and 10 percent stones; slightly acid (pH 6.2); clear wavy boundary. (2 to 4 inches thick)
AB--5 to 8 inches; dark grayish brown (10YR 4/2) stony loam, very dark brown (7.5YR 2/2) moist; weak medium subangular blocky structure parting to weak very fine granular; hard, very friable, slightly sticky and slightly plastic; common fine and few medium and coarse roots; many fine irregular and tubular pores; few uncoated silt grains; 10 percent gravel and 10 percent stones; slightly acid (pH 6.2); clear wavy boundary. (2 to 6 inches thick)
Bt1--8 to 18 inches; brown (10YR 5/3) stony loam, dark brown (10YR 3/3) moist; moderate fine and medium subangular blocky structure; very hard, friable, slightly sticky and slightly plastic; common fine and few medium and coarse roots; common very fine tubular pores; few fine dark concretions; few distinct clay films on faces of peds and in pores have slightly redder hue, darker value, and lower chromas than the interiors; very few uncoated silt grains; 10 percent gravel, 5 percent cobbles, and 15 percent stones; moderately acid (pH 6.0); clear wavy boundary. (7 to 16 inches thick)
Bt2--18 to 35 inches; brown (10YR 5/3) stony clay loam, dark brown (10YR 3/3) moist; very weak medium prismatic structure parting to moderate medium and fine subangular blocky; very hard, firm, moderately sticky and moderately plastic; few fine and medium roots; common very fine tubular pores; common fine dark concretions; common distinct clay films on faces of peds and in pores with slightly lower chroma than the interiors; 10 percent gravel, 5 percent cobbles, and 15 percent stones; moderately acid (pH 6.0); gradual wavy boundary. (10 to 20 inches thick)
Bt3--35 to 49 inches; brown (10YR 5/3) stony loam, brown (10YR 4/3) moist; moderate fine and very fine subangular blocky structure; very hard, firm, moderately sticky and moderately plastic; few fine roots; common very fine tubular pores; nearly continuous distinct clay films on vertical faces of peds that are slightly darker than the interiors; few fine dark concretions; 10 percent gravel, 5 percent cobbles, and 15 percent stones; moderately acid (pH 6.0); abrupt broken boundary. (7 to 20 inches thick)
R--49 inches; fractured sandstone.
TYPE LOCATION: Teton County, Idaho; about 4.4 miles west of Victor; 40 percent southerly slope at 6,400 feet elevation; 3,020 feet south and 820 feet east of the northwest corner of sec. 7, T. 3 N., R. 45 E.
RANGE IN CHARACTERISTICS:
Mollic epipedon thickness - 16 to 35 inches
Depth to bedrock - 40 inches or more
Depth to the argillic horizon - less than 10 inches
Particle-size control section:
Clay content - 18 to 35 percent
Rock fragment content - 20 to 35 percent
Mean annual soil temperature - 37 to 44 degrees F
Mean summer soil temperature - 54 to 59 degrees F
Soil moisture control section - dry for 45 to 60 consecutive days in late summer (Xeric)
A or Ap horizon
Color hue - 10YR or 7.5YR
value - 3 through 5 dry, 2 or 3 moist
chroma - 1 through 3 dry or moist
Texture - silt loam, gravelly silt loam or stony loam
Bt horizon
Color hue - 10YR or 7.5YR
value - 4 or 6 dry, 3 through 5 moist
chroma - 3 or 4 dry or moist
Texture - stony, very cobbly, very gravelly, cobbly, or gravelly: loam, clay loam, sandy clay loam, or silty clay loam
Reaction - moderately acid through neutral
BC horizons occur in some pedons.
Loamy C horizons are present in some pedons below 40 inches.
COMPETING SERIES: These are the Bachus, Bavdark, Benteen, Brushtop (T), Clayburn, Croydon, Crystalbutte, Davtone, Dehana, Demast, Dranburn, Echemoor, Hagenbarth, Hoopgobel (T), Millerlake, Odark (T), Pontuge (T), Senchert, Southmount, Squawval, Stubbs, Thulepah, Vadnais, and Winu series. Bachus, Benteen, Senchert, Vadnais, and Winu soils have bedrock at a depth of less than 40 inches. Bavdark and Croydon soils are deeper than 10 inches to the top of the argillic horizon. Brushtop soils have paralithic contact at depth of 40 to 60 inches. Clayburn soils are deeper than 15 inches to the Bt horizon, and have less than 20 percent rock fragments in the Bt horizon. Crystalbutte and Odark soils are 12 to 24 inches to the top of the argillic. Dehana soils have mollic epipedons more than 35 inches thick. Echemoor, Hoopgobel, Squawval and Stubbs soils have a paralithic contact at a depth of less than 40 inches. Davtone soils have 2.5YR or 5YR hue in the B2t horizon. Demast soils are 20 to 30 inches deep to the argillic horizon. Dranburn and Hagenbarth soils have less than 20 percent rock fragments in the particle-size control section. Millerlake soils are calcareous at depths of 15 to 40 inches. Pontuge soils have secondary calcium carbonate accumulation. Southmount soils are moderately well drained and have mottles above a depth of 40 inches. Thulepah soils are dry for more than 60 days in late summer.
GEOGRAPHIC SETTING: Dranyon soils are on mountain sideslopes and footslopes at elevations of 5,800 to 9,000 feet. Slopes are typically 20 to 35 percent and range from 0 to 65 percent. The soils formed mainly in residuum weathered from fine-grained sandstone or rhyolite, and contain some loess or colluvium or both in some pedons. The mean annual precipitation is 16 to 25 inches including 5 to 8 feet of snow. The mean annual air temperature is 35 to 42 degrees F. The frost-free season is 30 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dra, Robin, Greys, Mikesell, Nielsen, and Pavohroo soils. Dra, Greys, and Mikesell soils have a mollic epipedon less than 16 inches thick and have an E horizon. Nielsen soils have bedrock at a depth of less than 20 inches. Pavohroo soils lack an argillic horizon. In Robin soils, the upper boundary of the argillic horizon is below a depth of 24 inches.
DRAINAGE AND PERMEABILITY: Well drained; slow to very rapid runoff; moderately slow permeability.
USE AND VEGETATION: Used mainly for grazing and wildlife habitat. The natural vegetation is aspen, serviceberry, boxleaf myrtle, pinegrass, Oregon-grape, snowberry, wild geranium, wheatgrass, timothy, chokecherry, wild rose, and blue wildrye.
DISTRIBUTION AND EXTENT: Southern Idaho, northern Nevada, northwestern Colorado, and southeastern Utah. The series is extensive.
MLRA OFFICE RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Teton County, Idaho, 1973.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon (pachic feature) - 2 to 35 inches (A, AB, Bt1, and Bt2 horizons).
Argillic horizon - 8 to 49 inches (Bt1, Bt2, and Bt3 horizons).
Particle-size control section - 8 to 28 inches (Bt1 and part of the Bt2 horizons).