LOCATION WAPITI                  CO

Established Series
Rev. LAN/TLM
01/2014

WAPITI SERIES

The Wapiti series consists of very deep, well drained soils that formed in alluvium and eolian deposits derived from mixed sources. Wapiti soils are on plains, interfluves, drainageways, and terraces. Slopes range from 0 to 3 percent. Mean annual precipitation is about 381 millimeters (15 inches) and the mean annual temperature is about 11 degrees C (51 degrees F.)

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Calcidic Argiustolls

TYPICAL PEDON: Wapiti loam, on a north facing, nearly level, 1 percent slope at an elevation of 1,615 meters (5,300 feet). (Colors are for dry soil unless otherwise noted.) When described on February 27, 1974 the soil was moist from 0 to 30 centimeters (0 to 12 inches).

A--0 to 15 centimeters (0 to 6 inches); grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; neutral; abrupt smooth boundary. (15 to 20 centimeters thick)

Bt--15 to 36 centimeters (6 to 14 inches); brown (10YR 4/3) clay loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to moderate fine angular blocky; very hard, firm, moderately sticky and moderately plastic; common distinct, clay films on faces of peds; neutral (pH 7.2); clear smooth boundary. (18 to 51 centimeters thick)

Btk--36 to 69 centimeters (14 to 27 inches); pale brown (10YR 6/3) clay loam, brown (10YR 5/3) moist; weak medium prismatic structure parting to moderate fine subangular blocky; very hard, firm, moderately sticky and moderately plastic; common distinct clay films on faces of peds; 1 percent fine spherical distinct carbonate masses in matrix; violently effervescent; 12 percent calcium carbonate equivalent; moderately alkaline (pH 8.0); gradual smooth boundary. (20 to 36 centimeters thick)

Bk1--69 to 97 centimeters (27 to 38 inches); very pale brown (10YR 7/3) loam, yellowish brown (10YR 5/4) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; 10 percent fine spherical distinct carbonate masses in matrix; violently effervescent; 18 percent calcium carbonate equivalent; moderately alkaline (pH 8.2); clear smooth boundary. (20 to 46 centimeters thick)

BCk2--97 to 200 centimeters (38 to 79 inches); pink (7.5YR 7/3) clay loam, brown (7.5YR 5/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; 7 percent fie spherical distinct carbonate masses in matrix; violently effervescent; 8 percent calcium carbonate equivalent; moderately alkaline (pH 8.3).

TYPE LOCATION: Las Animas County, Colorado; about 23.3 kilometers (14.5 miles east of Kim, Colorado); located about 670 meters (2,200 feet) west and 762 meters (2,500 feet) south of the northeast corner of sec. 12, T. 32 S., R. 51 W. Sixth Principle Meridian; Utleyville, Colorado USGS topographic quadrangle; UTM zone 13 669271 E, 4126779 N; latitude 37 degrees 16 minutes 20 seconds N. and longitude 103 degrees 5 minutes 27 seconds W., NAD 83.

RANGE IN CHARACTERISTICS:

Soil moisture: Moist April through June and intermittently moist July through October. [Driest December through February]
Moisture regime: ustic bordering on aridic, including aridic bordering on ustic if irrigated.
Mean annual soil temperature: 10 to 12 degrees C (49 to 53 degrees F)
Mean summer soil temperature: 21 to 23 degrees C (70 to 74 degrees F)
Depth to base of the argillic horizon: 51 to 91 centimeters (20 to 36 inches)
Depth to secondary calcium carbonate: 25 to 36 centimeters (10 to 14 inches)
Depth to calcic horizon: 51 to 100 centimeters (20 to 40 inches)
Thickness of the mollic epipedon: 18 to 51 centimeters (7 to 20 inches)

Particle-size control section (weighted average):
Clay content: 18 to 35 percent
Sand content: 30 to 65 percent
Rock fragments: 0 to 15 percent

A horizon:
Hue: 10YR or 7.5YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 2 or 3
Texture: clay loam or loam
Clay content: 18 to 35 percent
Calcium carbonate equivalent: 0 to 2 percent
Reaction: neutral or slightly alkaline

Bt horizons:
Hue: 10YR or 7.5YR
Value: 4 or 5 dry, 3 or 4 moist
Chroma 2 to 4
Texture clay loam or sandy clay loam
Clay content: 20 to 35 percent
Calcium carbonate equivalent: 0 to 2 percent
Reaction: neutral or slightly alkaline

Btk horizon:
Hue: 10YR or 7.5YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma 3 or 4
Texture: clay loam or sandy clay loam
Clay content: 20 to 35 percent
Calcium carbonate equivalent: 5 to 15 percent
Reaction: slightly alkaline or moderately alkaline

Bk1 or BCk horizon:
Hue: 10YR or 7.5YR
Value: 6 to 8 dry, 5 to 7 moist
Chroma: 3 or 4
Texture: clay loam, sandy clay loam, loam, or fine sandy loam
Clay content: 17 to 30 percent
Calcium carbonate equivalent: 15 to 30 percent
Reaction: moderately alkaline or strongly alkaline

Bk2 horizon:
Hue 10YR to 7.5YR
Value 5 to 8 dry, 4 to 5 moist
Chroma: 2 to 4
Texture: clay loam, loam, sandy clay loam, fine sandy loam
Clay content: 12 to 30 percent
Rock fragments: 0 to 15 percent dominantly gravel, above 152 centimeters (60 inches), 0 to 25 percent below 152 centimeters (60 inches)
Calcium carbonate equivalent: 2 to 15 percent
Electrical Conductivity: 1 to 4 dS/m
Gypsum: 0 to 1 percent
Sodium Adsorption Ratio: 1 to 3
Reaction: moderately alkaline or strongly alkaline

COMPETING SERIES: These are the Asparas(NM), Capulin(NM), Chacuaco(NM), Rosebud(NE), and Ryegate(CO)series.
Asparas soils: are moderately alkaline in the A and Bt horizons and form in alluvium derived dominantly from limestone.
Capulin soils: have a lithic contact at depths of 100 to 152 centimeters (40 to 60 inches) and averages over 15 percent rock fragments in the lower part of the control section.
Chacuaco and Ryegate soils: have a lithic contact at depths of 51 to 100 centimeters (20 to 40 inches).
Rosebud soils: have a paralithic contact at depths of 51 to 100 centimeters (20 to 40 inches).

GEOGRAPHIC SETTING:
Parent material: Alluvium and eolian deposits derived from mixed sources.
Landform: Plains, interfluves, drainageways, and terraces
Slopes: 0 to 3 percent
Elevation: 1,219 to 1,829 meters (4,000 to 6,000 feet)
Mean annual temperature: 10 to 12 degrees C (50 to 53 degrees F)
Mean annual precipitation: 254 to 406 millimeters (10 to 16 inches)
Precipitation pattern:
Peak period: May through August
Driest period: December through February
Frost-free period: 125 to 170 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ascalon, Bacid, Chicosa, Olnest, and Tremontina series.
Ascalon and Olnest soils: have greater than 50 percent sand and are on hills and ridges.
Bacid soils: Bacid soils have a fine particle size control section and are on terraces.
Chicosa soils: Chicosa soils have a loamy-skeletal particle size control section and are on terraces.
Tremontina soils: Tremontina soils have a fine-silty particle size control section and are on terraces.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: well drained
Saturated hydraulic conductivity: moderately high or high

USE AND VEGETATION: Principal use is rangeland, irrigated and nonirrigated cropland. Native vegetation is western wheatgrass, sideoats grama, blue grama, buffalograss, bottlebrush squirreltail, and broom snakeweed. Loamy plains (R069XY006CO) ecological site.

DISTRIBUTION AND EXTENT: Southeast Colorado. LRR G, MLRA 67B and 69. The series is of moderate extent.

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

SERIES ESTABLISHED: Las Animas County, Colorado, Las Animas County Soil Survey Area, 2007. The name Wapiti (Wa-pee-tee) is coined from a Native American word for elk.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Series control section: 0 to 200 centimeters
Particle-size control section: The zone from 15 to 65 centimeters (6 to 26 inches). (Bt horizon and part of the Btk horizon)
Mollic epipedon: The zone from 0 to 36 centimeters (0 to 14 inches). (A and Bt horizon)
Argillic horizon: The zone from 15 to 69 centimeters (6 to 27 inches). (Bt and Btk horizons)
Calcic horizon: The zone from 69 to 97 centimeters (27 to 38 inches). (Bk1 horizon)

This soil was originally included in the Wages series. A consistent calcic horizon was found above a depth of 100 centimeters (40 inches), resulting the development of a new series.

This update converts English to metric and updates the competing series section and the location to NAD 83.

The assignment of the cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.

Taxonomic Version: Eleventh Edition, 2010

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National Cooperative Soil Survey
U.S.A.