LOCATION DRANYON                 ID+CO+UT+WY

Established Series
Rev. JEB/ALH/CBR
12/2022

DRANYON SERIES

The Dranyon series consists of deep or very deep, well drained soils that formed in colluvium from sandstone or rhyolite with loess influence. Dranyon soils are on mountain slopes with slopes of 0 to 60 percent. The mean annual precipitation is about 610 mm and the mean annual air temperature is about 2.5 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive Pachic Argicryolls

TYPICAL PEDON: Dranyon silt loam on a mountain slope with 22 percent slope at an elevation of 2,079 meters. (Colors are for dry soil unless otherwise noted.) The surface is covered by 1 percent cobbles and 1 percent boulders.

Oi--0 to 3 cm; slightly decomposed plant material; dried grasses and roots; clear smooth boundary. (0 to 3 cm thick)

A1--3 to 9 cm; dark brown (7.5YR 3/2) silt loam, black (10YR 2/1) moist; moderate fine granular structure; moderately hard, very friable, nonsticky and slightly plastic; many very fine and common fine and medium roots; many fine irregular and common fine tubular pores; 2 percent gravel; neutral (pH 7.2); clear wavy boundary.

A2--9 to 18 cm; dark brown (7.5YR 3/2) silt loam, black (10YR 2/1) moist; weak fine subangular blocky structure parting to weak fine granular; moderately hard, very friable, slightly sticky and slightly plastic; common very fine, fine, medium and coarse roots; many fine irregular and common fine tubular pores; 2 percent gravel; slightly alkaline (pH 7.4); clear wavy boundary. (Combined thickness of the A horizons is 7 to 30 cm)

AB--18 to 34 cm; brown (7.5YR 4/2) silt loam, dark brown (7.5YR 3/2) moist; moderate fine subangular blocky structure; hard, friable, moderately sticky and slightly plastic; common very fine, fine, medium and coarse roots; common fine tubular and irregular pores; 10 percent gravel; neutral (pH 6.8); gradual wavy boundary. (12 to 27 cm thick)

Bt1--34 to 53 cm; brown (7.5YR 5/3) stony silty clay loam, dark brown (7.5YR 3/3) moist; strong fine subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common coarse and few fine and medium roots; many fine irregular and tubular and common fine dendritic and medium tubular pores; few (10 percent) organic stains, few (10 percent) prominent skeletans and few (20 percent) distinct clay films on surfaces along pores; 10 percent gravel and 5 percent stones; neutral (pH 7.0); gradual wavy boundary. (19 to 33 cm thick)

Bt2--53 to 77 cm; pale brown (10YR 6/3) very stony silty clay loam, dark brown (7.5YR 3/4) moist; weak fine prismatic structure parting to strong fine subangular blocky; hard, friable, moderately sticky and moderately plastic; few fine and medium roots; many very fine and common fine and medium tubular pores; very few (2 percent) prominent skeletans, few (10 percent) organic stains and common (40 percent) distinct clay films on surfaces along pores and on all faces of peds; 15 percent cobbles, 15 percent stones and 10 percent gravel; neutral (pH 6.8); gradual wavy boundary. (10 to 24 cm thick)

Bt3--77 to 101 cm; light yellowish brown (10YR 6/4) silty clay loam, dark brown (7.5YR 3/4) moist; moderate fine prismatic structure parting to strong fine subangular blocky; hard, friable, moderately sticky and moderately plastic; few fine and medium roots; common very fine and medium tubular pores; very few (2 percent) prominent skeletans, few (5 percent) organic stains and common (35 percent) distinct clay films on surfaces along pores and on all faces of peds; one krotovina about 10 cm in length and 6 cm in width; 5 percent gravel; neutral (pH 6.8); clear wavy boundary.

Bt4--101 to 152 cm; light yellowish brown (10YR 6/4) clay loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; hard, very friable, moderately sticky and moderately plastic; common coarse and few fine roots; common fine tubular and irregular pores; few (5 percent) organic stains and few (10 percent) faint clay films; 10 percent sandstone gravel, some fragments weathering in place; neutral (pH 6.8).

TYPE LOCATION: Teton County, Idaho; about 3.1 km northeast of Victor; 155 meters east and 316 meters south of the northwest corner of section 6, T. 3 N., R. 46 E.; Victor USGS topographic quadrangle; lat. 43 degrees, 37 minutes, and 6.6 seconds N. and long. 111 degrees, 4 minutes, 46.5 seconds W., NAD83.

RANGE IN CHARACTERISTICS:
Mollic epipedon thickness: 40 to 89 cm
Depth to argillic horizon: 24 to 50 cm
Particle size control section average rock fragments: 20 to 35 percent
Particle size control section average clay: 18 to 35 percent
Depth to bedrock: greater than 100 cm
Soil moisture regime: Udic
Mean annual soil temperature: 2.8 to 6.7 degrees C. (cryic soil temperature regime)
Mean summer soil temperature: 5.5 to 8.0 degrees C. and in areas where an O horizon is lacking, the soil temperature is 10.0 to 15.0 degrees C

A or Ap horizon
Hue: 7.5YR or 10YR moist or dry
Value: 2 to 3 moist, 3 to 5 dry
Chroma: 1 to 3 moist or dry
Texture: SIL, GR-SIL, or ST-L

AB or BA horizon
Value: 2.5 or 3 moist
Chroma: 2 or 3 moist
Texture: SIL or GR-SIL with 10 to 20 percent gravel

Bt horizon
Hue: 7.5YR or 10YR moist or dry
Value: 3 to 5 moist, 4 to 6 dry
Chroma: 2 to 4 moist, 3 or 4 dry
Fine-earth texture: L, CL, SCL, SICL, SIL stony, very stony, very cobbly, very gravelly, cobbly, or gravelly.
Reaction: moderately acid through neutral

COMPETING SERIES: These are the Bachus, Bavdark, Benteen, Brushtop, Clayburn, Croydon, Crystalbutte, Davtone, Dehana, Demast, Dranburn, Echemoor, Hagenbarth, Hoopgobel, Lostminer, Millerlake, Odark, Pontuge, Senchert, Southmount, Poodle, Stubbs, Thulepah Vadnais, and Winu soil series. Bachus, Benteen, Echemoor, Hoopgobel, Lostminer, Senchert, Poodle, Stubbs, Vadnais, and Winu soils are moderately deep. Bavdark and Odark soils have an ustic soil moisture regime. Clayburn soils have less than 20 percent rock fragments in the particle size control section. Davtone soils have hues of 5YR or redder in the particle size control section. Croydon soils have a mollic epipedon 27 to 40 cm thick. Dranburn, and Hagenbarth soils have less than 20 percent rock fragments in the particle size control section and have a xeric soil moisture regime. Crystalbutte soils have greater than 35 percent rock fragments below the particle size control section. Dehana soils have a molllic epipedon that is greater than 89 cm thick. Demast soils are greater than 50 cm to an argillic horizon. Millerlake and Pontuge soils have secondary carbonates within the particle size control section. Southmount soils are moderately well drained with reodox features at 45 to 100cm. Brushtop and Thulepah soils have a xeric soil moisture regime.

GEOGRAPHIC SETTING:
Landscape: mountains
Landform: mountain slopes
Elevation: 1,768 to 2,743 meters
Slope: 0 to 60 percent
Parent material: colluvium from sandstone or rhyolite with loess influence
Mean annual air temperature: 1.7 to 5.6 degrees C.
Mean annual precipitation: 406 to 914 mm
Frost free period: 30 to 80 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dra and Greys soils. Dra soils have a loamy-skeletal particle size class and occur on convex positions. Greys soils have a fine-silty particle size class and occur on concave positions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: well drained
Runoff: very high
Saturated hydraulic conductivity: moderately low

USE AND VEGETATION:
Major uses: grazing and wildlife habitat
Dominant native vegetation: aspen, Woods rose, snowberry, sticky geranium, pine reedgrass, mountain brome, blue wildrye

DISTRIBUTION AND EXTENT:
Distribution: southern Idaho, western Wyoming, northern Nevada, northern Utah, and northwestern Colorado, MLRA 13, 25, 34A, 34B, 47, and 48A
Extent: the series is moderately extensive

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Teton County, Idaho, 1973; Teton Area, Idaho-Wyoming Soil Survey

REMARKS:
Diagnostic horizons and soil characteristics recognized in this pedon are:
Mollic epipedon: from a depth of 3 to 53 cm
Argillic horizon: from a depth of 34 to 152 cm
Particle size control section: from a depth of 34 to 84 cm and weighted average is 26 percent rock fragments
Soil temperature regime: cryic
Soil moisture regime: udic

In 2010, the Dranyon typical pedon location was relocated within Teton County because the pedon was not found at the original location. At that time the series was defined as having a udic soil moisture regime. This udic correlation is based on the native vegetation being aspen. In the past the soil may have been correlated as having a xeric soil moisture regime as the moisture regime in older versions of the description was not identified. Review of map unit components in previously correlated soil surveys is needed. In 1978 the series was defined as deep to a lithic contact. In 1980 the series was re-defined to be deep and very deep to bedrock thus some of the competing series criteria are minimal.

ADDITIONAL DATA:
Typical pedon was not sampled.

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National Cooperative Soil Survey
U.S.A.