LOCATION CUCHARAS           CO
Established Series
Rev. LAN/GB/AP
11/2007

CUCHARAS SERIES


The Cucharas series consists of moderately deep, well drained, slowly permeable soils that formed in slope alluvium and residuum from shale. Cucharas soils are on mountain slopes, hills and hilltops. Slopes range from 5 to 40 percent. The mean annual precipitation is about 24 inches and the mean annual temperature is about 42 degrees F.

TAXONOMIC CLASS: Fine, smectitic Vertic Argicryolls

TYPICAL PEDON: Cucharas clay loam - mountain meadow. (Colors are for dry soil unless otherwise noted.)

A--0 to 10 inches; dark gray (10YR 4/1) clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; slightly hard, friable, sticky and plastic; slightly acid (pH 6.4); clear wavy boundary (5 to 15 inches).

Bt--10 to 26 inches; grayish brown (10YR 5/2) clay, dark grayish brown (10YR 4/2) moist and crushed; common very fine faint light olive brown (2.5Y 5/6) mottles; strong coarse prismatic structure parting to strong medium subangular blocky; very hard, very firm, very sticky and very plastic; many thin clay films on ped faces; slightly acid (pH 6.2); gradual smooth boundary (10 to 20 inches).

BCt--26 to 32 inches; grayish brown (2.5Y 5/2) clay, dark grayish brown (2.5Y 4/2) moist and crushed; common fine faint light olive brown (2.5Y 5/6) mottles; moderate fine and medium subangular blocky structure; very hard, very firm, very sticky and very plastic; few thin clay films on ped faces; 5 percent stable shale fragments; neutral (pH 6.6); clear wavy boundary (5 to 10 inches).

Cr--32 inches; soft gray shale.

TYPE LOCATION: Las Animas County, Colorado; approximately .5 miles from Colorado Highway 12 and Bear Creek; about 550 feet north and 550 feet east of the southwest corner of Sec. 36, T. 31 S., R. 69 W; longitude: 105 degrees, 3 minutes, 39 seconds north; latitude: 37 degrees, 17 minutes, 48 seconds west.

RANGE IN CHARACTERISTICS:
Soil Moisture: Moist continuously from March through Septmeber. Soil moisture regime is udic bordering on ustic.
Mean annual soil temperature ranges from 40 to 44 degrees F.
Mean summer soil temperature ranges from 52 to 58 degrees F.
Depth to paralithic contact is 20 to 40 inches.
The mollic epipedon ranges from 7 to 15 inches thick.
Vertic features: Cracks 1 cm. wide occur at depths of 20 inches or more and extend to the surface in dry periods.
Thickness of the argillic horizon: 10 to 30 inches.

The A horizon:
Hue: 7.5YR to 2.5Y
Value: 3 or 4 dry, 2 or 3 moist
Chroma: 1 to 3.
Reaction is slightly acid or neutral.

The Bt horizon:
Hue: 7.5YR to 2.5Y
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 2 or 3.
Texture: clay, silty clay
Clay content: 35 to 55 percent.
Reaction: slightly acid or neutral

The BCt horizon:
Hue: 7.5YR to 2.5Y
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 to 4
Texture: clay, silty clay, clay loam
Clay content: 35 to 55 percent
Parafragment content: 5 to 25 percent
Reaction: slightly acid to slightly alkaline

COMPETING SERIES: These are the Beaverdam(ID), Buckskin (ID), Cimarron (CO), Gillum (SD), Gourley (CO), Hairpin (MT), Heathcoat (ID), Helmet (CO), Savar (WY), Slights (ID), Suddeth (CO), Sudpeak (ID), Toponce(ID), Wetopa (CO) and Youman (CO) series.
Beaverdam, Buckskin, Cimarron, Gillum, Gourley, Hairpin, Heathcoat, Helmet, Savar, Slights, Suddeth, Sudpeak, Toponce, Wetopa, and Youman soils are greater than 40 inches to bedrock.

GEOGRAPHIC SETTING:
Parent material: slope alluvium and residuum from shale.
Landform: mountain slopes, hills and hilltops.
Elevation: 8,000 to 10,000 feet
Slopes range from 5 to 40 percent.
Mean annual precipitation ranges from 22 to 26 inches.
Wettest period: April through August
Driest period: December through February
Mean annual temperature ranges from 40 to 43 degrees F.
The frost-free season ranges from 40 to 70 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Crooked Creek, Graneros, Groomer, and Tercio soils. Crooked Creek soils are very deep, have an aquic moisture regime, and are on toeslopes and drainageways.
Graneros soils lack a mollic epipedon and have an albic horizon.
Groomer and Tercio soils lack bedrock above a depth of 40 inches.

DRAINAGE AND PERMEABILITY: Well drained; runoff is rapid; permeability is very slow.

USE AND VEGETATION: Cucharas soils are used primarily for livestock grazing and wildlife habitat. Vegetation is mainly Arizona fescue, Parry oatgrass, mountain brome, Thurber's fescue, alpine timothy, and small amounts of shrubs.

DISTRIBUTION AND EXTENT: Mountain areas of southeastern Colorado. This series is of small extent.

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

SERIES ESTABLISHED: Las Animas County, Colorado, 2007. The name is taken from Cucharas Pass and is Spanish for spoons.

REMARKS:
Diagnostic horizons and features recognized in this pedon:
Particle size control section: The zone from 10 to 32 inches (Bt and BCt horizons)
Mollic epipedon: the zone from 0 to 10 inches (A horizon).
Argillic horizon: the zone from 10 to 32 inches (Bt and BCt horizon).
Paralithic contact at a depth of 32 inches.
Vertic features: large cracks in the surface and argillic horizons, often extending down to the bedrock.
Last update by the state 5/89.

Taxonomic Version: Eighth Edition, 1998


National Cooperative Soil Survey
U.S.A.