LOCATION VENABLE CO+WYEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive Cumulic Cryaquolls
TYPICAL PEDON: Venable loam - rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 5 inches; very dark gray (10YR 3/1) loam, black (10YR 2/1) moist; moderate medium granular structure; soft, very friable; neutral; clear smooth boundary. (4 to 12 inches thick)
Ag--5 to 23 inches; very dark gray (10YR 3/1) loam, black (10YR 2/1) moist; weak medium granular structure; slightly hard, very friable, slightly sticky; common fine prominent red (2.5YR 5/8) iron concentrations; neutral; gradual wavy boundary. (10 to 25 inches thick)
ACg--23 to 44 inches; very dark gray (10YR 3/1) loam, black 10YR 2/1) moist; weak coarse prismatic and subangular blocky structure; very hard, friable, slightly sticky; common prominent dark yellowish brown (10YR 4/8) iron concentrations; neutral; gradual wavy boundary. (10 to 24 inches thick)
Cg--44 to 60 inches; light brownish gray (2.5Y 6/2) loam, grayish brown (2.5Y 5/2) moist; massive; very hard, friable, slightly sticky; common coarse distinct yellowish brown (10YR 5/8) iron concentrations; neutral.
TYPE LOCATION: Custer County, Colorado; about 11 miles south of Westcliffe; about 2,050 feet north and 600 feet west of the southeast corner of Sec. 7, T. 24 S., R. 72 W.; Beck Mt. U.S.G.S. quad; Lat. 37 degrees, 58 minutes, 38 seconds N., and long. 105 degrees, 28 minutes, 39 seconds W.
RANGE IN CHARACTERISTICS:
Soil moisture regime: udic, usually moist when the soil temperature is greater than 41 degrees F.
Mean annual soil temperature: 40 to 44 degrees F.
Mean summer soil temperature: 51 to 54 degrees F.
Thickness of the mollic epipedon: 20 to 50 inches
Depth to endosaturation (in normal years): 5 to 20 inches
Particle-size control section
Clay content: 18 to 35 percent
Rock fragment content: 0 to 15 percent, dominantly gravel
A horizon
Hue: 7.5YR or 10YR
Value: 3 or 4 dry, 2 or 3 moist
Chroma: 1 or 2.
Clay content: 18 to 35 percent
Rock fragment content: 0 to 15 percent
Reaction: slightly acid to slightly alkaline
C horizon
Hue: 5Y through 7.5YR.
Clay content: 10 to 20 percent
Rock fragment content: 0 to 15 percent
Reaction: neutral or slightly alkaline
COMPETING SERIES: This is the Wiskisprings series. Wiskisprings soils have a lithologic discontinuity with sandy materials and are dry in some parts of the moisture control section more than 30 days when the soil temperature is greater than 41 degrees F.
GEOGRAPHIC SETTING: The Venable soils are on alluvial valley floors, low terraces, flood plains, and drainageways of mountain valleys. Slopes range from 0 to 10 percent. elevations are 7,200 to 9,500 feet. The soils formed in medium textured alluvium. Mean annual precipitation is 17 to 23 inches and the average annual temperature is 38 to 42 degrees F. The frost free period is 40 to 75 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Becks, Curecanti, and Wichup soils. Becks and Curecanti soils are skeletal, and Curecanti soils also have an argillic horizon and are well to moderately well drained. Wichup soil s have a histic epipedon.
DRAINAGE AND PERMEABILITY: Poorly drained; slow runoff; moderate permeability.
USE AND VEGETATION: These soils are used as native pasture and for irrigated meadow hayland. Native vegetation is mainly Thurber fescue, slender wheatgrass, alpine timothy, and sedges. Along stream banks, willows are common.
DISTRIBUTION AND EXTENT: Mountain valleys of southern central Colorado. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Custer County, Colorado, 1979.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 44 inches (A, Ag, and ACg horizons)
Cumulic feature - an irregular decrease in organic matter is inferred from the landscape position and from the thick epipedon.
Aquic conditions (endosaturation) - from 5 to 60 inches (in normal years) inferred from redoximorphic features and low chroma of the matrix (Ag, ACg, and Cg horizons)
Keys to Soil Taxonomy: Series classified according to Eighth Edition, 1998.
The superactive CE activity class is presumed for this series based on the general trend indicated by lab data throughout this region.
ADDITIONAL DATA: