LOCATION WOODHALL                CO+MT

Established Series
Rev. RHM/CRP/JCK
03/2018

WOODHALL SERIES

The Woodhall series consists of moderately deep, well drained soils that formed in slope alluvium, colluvium or slide deposits derived from igneous and sedimentary rock. These soils are on mountain slopes, dip slopes, structural benches, hills and landslides. Slopes are 3 to 65 percent. Mean annual precipitation is about 585 mm, and mean annual air temperature is about 3.3 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Ustic Argicryolls

TYPICAL PEDON: Woodhall stony loam - mixed grass and timber. (Colors are for dry soil unless otherwise noted.)

A--0 to 13 cm; dark grayish brown (10YR 4/2) stony loam, very dark brown (10YR 2/2) moist; strong fine granular and crumb structure; soft, very friable, slightly plastic; 20 percent stones; neutral (pH 7.0); clear smooth boundary. (18 to 25 cm thick)

Bt1--13 to 23 cm; brown (10YR 5/3) very stony loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure parting to strong fine granular; hard, friable, slightly plastic; few faint clay films on faces of peds and on surfaces along in some root channels; 40 percent stones; neutral (pH 7.0); gradual smooth boundary. (0 to 15 cm thick)

Bt2--23 to 51 cm; brown (10YR 5/3) very stony clay loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; very hard, friable, sticky and plastic; many distinct clay films on faces of peds, on surfaces along root channels and on surfaces of many rock fragments; 50 percent stones; neutral (pH 6.8); gradual smooth boundary. (15 to 74 cm thick)

BC--51 to 61 inches; brown (10YR 5/3) extremely stony loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; very hard, friable, slightly plastic; 60 percent stones; neutral (pH 6.8); gradual wavy boundary. (0 to 36 cm thick)

R--61 cm; rhyolite.

TYPE LOCATION: Gunnison County, Colorado; near the center of Sec. 1, T. 46 N., R. 3 W.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 2.7 to 5.4 C
Mollic epipedon thickness - 18 to 40 cm
Depth to lithic contact - 50 to 100 cm
Particle-size control section (weighted average):
Clay content - 18 to 35 percent
Rock fragments - 35 to 75 percent, dominantly greater than 250 mm
A horizon
Hue: 5Y, 2.5Y, 10YR or 7.5YR
Value: 3, 4 or 5 dry; 2 or 3 moist
Chroma: 1, 2 or 3
Texture: loam or sandy loam
Clay content: 12 to 26 percent
Rock fragments: 0 to 35 percent
Reaction: pH 6.4 to 7.2

Bt1 horizon
Hue: 5Y, 2.5Y, 10YR or 7.5YR
Value: 3, 4 or 5 dry; 2 or 3 moist
Chroma: 2 or 3
Texture: clay loam, sandy clay loam or loam
Clay: 18 to 35 percent
Rock fragments: 35 to 75 percent
Reaction: pH 6.4 to 7.2


Bt2 horizon
Hue: 5Y, 2.5Y, 10YR or 7.5YR
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2, 3 or 4
Texture: clay loam, sandy clay loam or loam
Clay: 18 to 35 percent
Rock fragments: 35 to 75 percent
Reaction: pH 6.4 to 7.0

BC horizon
Hue: 5Y, 2.5Y, 10YR or 7.5YR
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2, 3 or 4
Texture: loam, fine sandy loam, or sandy loam
Clay content: 5 to 18 percent
Rock fragments: 35 to 75 percent
Reaction: pH 6.2 to 7.0

Some pedons have a C horizon in place of a BC.

COMPETING SERIES:
Anniesdraw soils (WY) - are very deep
Bassel soils (CO) - are deep to a paralithic contact
Blaine soils (MT) - have secondary calcium carbonate accumulation
Bowen soils - (CO) have mica fragments throughout the profile
Fingerrock soils (CO) - are very deep
Fornor soils (WY) - are very deep
Fourmile soils (CO) - are very deep
Geertsen soils (UT) - are deep to a lithic contact
Hoodle soils (UT) - are very deep
Hungryhill (MT) - rock fragments are dominantly less than 250 mm
Lagarita (CO) - are very deep
Lambe soils (CO) - are very deep
Libeg soils (MT) - are very deep
Nathale soils (WY) - have a calcic horizon
Nathrop (CO) - have secondary calcium carbonate accumulation
Norriston (CO) - are very deep
Quander soils (CO) - are very deep
Ratiopeak soils (MT) - are very deep
Silverheels soils (CO) - are very deep
Spanpeak soils (MT) - are very deep

GEOGRAPHIC SETTING:
Landform - mountain slopes, dip slopes, structural benches, hills and landslides
Elevation - 1,700 to 3,500 meters
Slope - 2 to 60 percent
Parent material - slope alluvium, colluvium or slide deposits
Mean annual precipitation - 457 to 660 mm
Mean annual air temperature - 1.7 to 4.4 C
Frost-free period - 30 to 75 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ruby and Vulcan soils.

DRAINAGE AND PERMEABILITY: Well drained; moderate to moderately slow permeability.

USE AND VEGETATION: Woodhall soils are used for rangeland, wildlife habitat, recreation and some timber production. Native vegetation is slender wheatgrass, mountain brome, Columbia needlegrass, Geyer's sedge, snowberry, quaking aspen, Douglas fir and ponderosa pine.

DISTRIBUTION AND EXTENT: Woodhall soils are of moderate extent in mountain areas of Colorado and Montana; MLRA 43B and 48A.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Gunnison County, Colorado, 1971.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 23 cm (A and Bt1 horizons)
Argillic horizon - from 23 to 51 cm (Bt1 and Bt2 horizons)
Lithic contact - at 61 cm (R horizon)

Woodhall soils have a cryic temperature regime and a udic moisture regime bordering on ustic.

---

National Cooperative Soil Survey
U.S.A.