LOCATION CHAFFEE                 CO

Established Series
Rev. RHM//AWS/TWH
05/2012

CHAFFEE SERIES

The soils of the Chaffee series are deep, poorly to somewhat poorly drained soils formed in alluvial or glacial outwash material from mixed sources. They are on flood plains, flood-plain steps, low terraces, fans, or glacial outwash channels. Mean annual precipitation is about 12 inches and the mean annual air temperature is about 44 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Cumulic Endoaquolls

TYPICAL PEDON: Chaffee sandy loam - grassland. (Colors are for dry soil unless otherwise noted.)

Ag1--0 to 11 inches; dark grayish brown (10YR 4/2) sandy loam, very dark brown (10YR 2/2) when moist; common, medium, distinct, brown (7.5YR 4/4) moist redox concentrations; moderate, fine, granular structure; soft, very friable; noncalcareous; slightly alkaline; gradual, smooth boundary. (0 to 40 inches thick)

Ag2--11 to 32 inches, grayish brown (2.5Y 5/2) sandy loam, very dark grayish brown (2.5Y 3/2) when moist, many large, prominent, strong brown (7.5YR 5/6) moist redox concentrations and very dark gray (2.5Y 3/1) moist redox depletions; weak, fine, subangular blocky structure; slightly hard, very friable; noncalcareous; slightly alkaline; gradual, smooth boundary. (0 to 40 inches thick)

Bg--32 to 50 inches; grayish brown (2.5Y 5/2) sandy loam, dark grayish brown (2.5Y 4/2) when moist; many, large, distinct, brown (7.5YR 4/4) moist redox concentrations; massive; slightly hard, very friable; noncalcareous; slightly alkaline; gradual, wavy boundary. (0 to 16 inches thick)

2Cg--50 to 60 inches; sand, gravel, and cobbles; noncalcareous.

TYPE LOCATION: Chaffee County, Colorado; 600 feet south and 200 feet east of the NW corner of Sec. 12, T. 49 S., R. 8 E.

RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon: 24 to 50 inches (60 to 127 centimeters)
A mottled cambic horizon of low chroma typically occurs below the mollic epipedon, but in some pedons the mollic epipedon extends to the sandy-skeletal 2C horizon.
Depth to uniformly calcareous material: 40 to greater than 60 inches (100 to greater than 152 centimeters), in some pedons the surface few inches are weakly calcareous due to recharge.
Depth to the sandy-skeletal material: 40 to 60 inches (100 to 152 centimeters)
Rock fragments range from 0 to 35 percent by volume in a major part of the control section and range from 1/4 to 10 inches in diameter but are usually less than 3 inches in diameter.

Particle-size control section (weighted average):
Clay content: 5 to 18 percent
Sand content: 50 to 80 percent (more than 35 percent fine or coarser sand)
Silt content: 5 to 35 percent

A horizon:
Hue: 5Y to 7.5YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 0 to 2
Rock fragment content: 0 to 35 percent, mainly gravel and some cobble
Reaction: slightly acid to slightly alkaline

Bg horizon:
Hue: 5Y to 7.5YR
Value: 5 to 7 dry, 3 to 6 moist
Rock fragment content: 0 to 35 percent, mainly gravel and some cobble
Chroma: 0 to 2
Reaction: slightly acid to slightly alkaline

COMPETING SERIES:
Conway soils do not have sandy-skeletal 2C horizons.
Seeya soils have greater than 15 percent rock fragments in the particle size control section.
Schrader soils do not have sandy-skeletal 2C horizons.

GEOGRAPHIC SETTING:
Parent Material: alluvium or glacial outwash derived from a variety of rock sources
Landform: gently sloping concave portions of flood plains, flood-plain steps, low terraces, alluvial fans, glacial outwash channels
Slopes: 0 to 6 percent
Mean annual precipitation: At the type location the average annual precipitation is 12 inches (30 centimeters)
Precipitation pattern: peak periods of precipitation in the spring and summer
The mean annual temperature is 44 degrees F, and the mean summer temperature is 62 degrees F.
Frost-free period: 95 to 105 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Gas Creek soils occur on the same landforms or higher landforms and are coarse textured and have mollic epipedons less than 24 inches thick.
Sawatch soils occur on the same landforms and have histic epipedons.

DRAINAGE AND PERMEABILITY:
Drainage: poorly to somewhat poorly drained
Runoff: slow
Saturated hydraulic conductivity: moderately high to high (permeability is restricted because of a high water table)

USE AND VEGETATION: These soils are used primarily as native pastureland or as native hayland. Native vegetation is water-tolerant grasses, sedges, and rushes.

DISTRIBUTION AND EXTENT: High mountain valleys of central Colorado. LRR E, MLRA 48A and 49. This series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Chaffee County, Colorado, 1974.

REMARKS:
Diagnostic horizons and features recognized in this pedon:
Mollic epipedon: 0 to 81 centimeters (0 to 32 inches) (Ag1 and Ag2 horizons)
Particle-size control section: The zone from 25 to 100 centimenters (10 to 40 inches) (Ag1, Ag2, and Bg horizons)

Taxonomic Version: Eleventh Edition, 2010

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National Cooperative Soil Survey
U.S.A.