LOCATION WILID CO

Established Series
WSH/LC
08/2012

WILID SERIES

The Wilid series consists of very deep, well drained soils that formed in loess. Wilid soils are on plains and interfluves in MLRA 69. Slopes range from 0 to 12 percent. The mean annual precipitation is about 305 millimeters (12 inches). The mean annual temperature is about 11 degrees C (52 degrees F).

TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Ustic Calciargids

TYPICAL PEDON: Wilid silt loam, nearly level slope in rangeland at an elevation of 1601 meters (5,250 feet). (Colors are for dry soil unless otherwise noted).

A--0 to 15 cm (0 to 6 inches); pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; weak fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; slight effervescence; slightly alkaline (pH 7.8); clear smooth boundary. (5 to 15 cm thick)

Bt--15 to 25 cm (6 to 10 inches); pale brown (10YR 6/3) silty clay loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; moderately hard, firm, moderately sticky and moderately plastic; common very fine and fine roots; few very fine pores; 30 percent distinct clay films on all faces of peds; violent effervescence; 7 percent calcium carbonate equivalent; moderately alkaline (pH 8.2); clear smooth boundary.

Btk--25 to 76 cm (10 to 30 inches); pale brown (10YR 6/3) silty clay loam, brown (10YR 5/3) moist; moderate medium subangular blocky structure; very hard, firm, moderately sticky and moderately plastic; few very fine roots; few very fine pores; 30 percent distinct clay films on all faces of peds; 1 percent medium distinct carbonate masses throughout; violent effervescence; 8 percent calcium carbonate equivalent; moderately alkaline (pH 8.2); clear smooth boundary. (Combined thickness of Bt and Btk horizons is 28 to 84 cm)

Bk1--76 to 112 cm (30 to 44 inches); pale brown (10YR 6/3) silty clay loam, brown (10YR 5/3) moist; weak medium subangular blocky structure; very hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine pores; 5 percent medium carbonate masses throughout; violent effervescence; 17 percent calcium carbonate equivalent; moderately alkaline (pH 8.2); clear wavy boundary. (25 to 50 cm thick)

Bk2--112 to 200 cm (44 to 79 inches); very pale brown (10YR 7/4) silt loam, yellowish brown (10YR 5/4) moist; weak course subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine pores; 25 percent fine faint carbonate masses throughout; violent effervescence; 25 percent calcium carbonate equivalent; moderately alkaline (pH 8.2).

TYPE LOCATION: Las Animas County, Colorado; approximately 10 miles east and 2 miles north of Model; 900 feet east and 2,450 feet north of the southwest corner of Sec. 29, T. 29 S., R. 30 W.; Brown Sheep Camp, CO, USGS quad.; UTM zone 13 585004 E, 4139858 N; latitude 37 degrees, 24 minutes, 5.8 seconds N. and longitude 104 degrees, 2 minutes, 22.5 seconds W., NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Moist in some part March through May and intermittently moist June through October. It is driest December through February.
Moisture regime: aridic bordering on ustic.
Mean annual soil temperature: 9 to 12 degrees C. (49 to 54 degrees F.)
Depth to secondary calcium carbonate: 0 to 25 centimeters (0 to 10 inches)
Depth to calcic horizon: 66 to 127 cm (26 to 50 inches)
Thickness of the argillic horizon: 28 to 84 centimeters (11 to 33 inches)

Particle size control section:
Clay content: 24 to 35 percent
Silt content: 50 to 70 percent
Sand content: 5 to 20 percent, with less than 15 percent fine or coarser sand.

A horizon:
Hue: 10YR
Value: 4 through 6, 3 or 4 moist
Chroma: 2 or 3
Texture: silt loam, silty clay loam
Reaction: neutral through moderately alkaline

Btk and Bt horizons:
Hue: 10YR
Value: 5 or 6, 4 or 5 moist
Chroma: 3 or 4
Texture: silt loam or silty clay loam
Calcium carbonate equivalent: 5 to 15 percent (5 to 10 percent in Bt horizons)
Reaction: moderately alkaline or strongly alkaline

Bk horizons:
Hue: 10YR
Value: 6 through 8, 5 or 6 moist
Chroma: 2 through 4
Texture: silt loam, loam or silty clay loam
Calcium carbonate equivalent: 5 to 25 percent above 100 cm, 10 to 40 percent below 100 cm.
Reaction: moderately alkaline or strongly alkaline

COMPETING SERIES: These are the Almagre (CO), Monogram (CO), Snapill (NM), Tetilla (NM), Villedry (CO), and Witt (NM) series.
Almagre soils: have a lithic contact at depths of 100 to 150 cm, 40 to 60 inches.
Monogram soils: have calcium carbonate equivalent of 40 to 70 percent in the calcic horizon and a lithic contact at 168 cm, 66 inches.
Snapill soils: have a paralithic contact at depths of 50 to 100 cm, 40 to 60 inches.
Tetilla soils: have 10 to 25 percent rock fragments in the Bk2 horizon.
Villedry soils: have a lithic contact at depths of 50 to 100 cm, 40 to 60 inches.
Witt soils: the soil moisture control section is driest during May and June and have hues redder than 10YR.

GEOGRAPHIC SETTING:
Landform: plains and interfluves
Slopes: range from 0 to 12 percent
Parent material: loess
Mean annual precipitation: 254 to 356 millimeters (10 to 14 inches), most of which falls during the months of April through September. Driest period is December through February.
Mean annual air temperature: 9 to 12 degrees C. (49 to 53 degrees F.)
Average summer temperature: 20 to 23 degrees C. (68 to 74 degrees F.)
Frost-free season: 130 to 175 days
Elevation ranges from 1219 to 1981 meters (4,000 to 6,200 feet).

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bacid, Manzanola, Minnequa and Fort soils. Bacid and Manzanola soils are in the fine family and are in depressions and drainageways. Minnequa soils are on pediments that have a thin loess cap over residuum. They have a paralithic contact at depths of 51 to 100 cm. Fort soils have a fine-loamy control section and are on side slopes of interfluves and ridges.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; low or medium runoff; moderately high to high hydraulic conductivity.

USE AND VEGETATION: These soils are rangeland or nonirrigated cropland. Native vegetation is mainly blue grama, galleta, sand dropseed, and western wheatgrass. It is correlated to the Loamy Ecological Site Description.

DISTRIBUTION AND EXTENT: MLRA 69. This series is extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado

SERIES ESTABLISHED: Lincoln County, Colorado, 1996.

REMARKS: Diagnostic horizons and features in this pedon are:
Ochric epipedon: 0 to 15 centimeters (0 to 6 inches).
Argillic horizon: 15 to 76 centimeters (6 to 30 inches).
Calcic horizon: 76 to 200 centimeters (30 to 79 inches).

The Wilid series replaces Wiley in the Ustic-Aridic moisture regime. The Wiley series was reclassified from Ustic Haplargids to Aridic Haplustalfs. The name Wilid is coined from Wiley.
LC 11/2011 Revised horizon nomenclature, properties ranges, and updated to metric format based on reexamination of correlation samples, documentation, and field office laboratory measurements.

LAN 5/2012 This update moves the type location from Lincoln County, Colorado to Las Animas County, Colorado and changes the Taxonomic class to Fine-silty, mixed, superactive, mesic Ustic Calciargids.

Keys to Soil Taxonomy used: Eleventh Edition, 2010

National Cooperative Soil Survey
U.S.A.