LOCATION MINQWET CO

Established Series
LAN
01/2014

MINQWET SERIES

The Minqwet series consists of moderately deep, well drained soils that formed in loess and residuum derived from calcareous shale and limestone. Minqwet soils are on hills, ridges and pediments in the plains. Slopes range from 1 to 10 percent. Mean annual precipitation is about 381 millimeters (15 inches) and the mean annual temperature is about 11 degrees C (52 degrees F).

TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Aridic Haplustepts

TYPICAL PEDON: Minqwet silt loam, on an east facing, 3 percent slope in grass at an elevation of 1,628 meters (5,344 feet). (Colors are for dry soil unless otherwise noted.) When described on October 11, 2001 the soil was dry from 0 to 76 centimeters (0 to 30 inches).

A--0 to 15 centimeters (0 to 6 inches); brown (10YR 5/3) silt loam, brown (10YR 4/3) moist; moderate fine and medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; 22 percent calcium carbonate equivalent; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (10 to 18 centimeters (4 to 7 inches) thick

Bw1--15 to 36 centimeters (6 to 14 inches); light brownish gray (10YR 6/2) silty clay loam, brown (10YR 4/3) moist; moderate fine and medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; 28 percent calcium carbonate equivalent; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary.

Bw2--36 to 53 centimeters (14 to 21 inches); very pale brown (10YR 7/3) silty clay loam, yellowish brown (10YR 5/4) moist; moderate fine and medium subangular blocky structure; few very fine and fine roots; 32 percent calcium carbonate equivalent; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (Combined thickness of the Bw horizons is 30 to 53 centimeters (12 to 21 inches))

Bky--53 to 76 centimeters (21 to 30 inches); very pale brown (10YR 7/3) silty clay loam, yellowish brown (10YR 5/4) moist; weak fine and medium subangular blocky structure; few very fine and fine roots; 5 percent shale parafragments; few medium soft masses of calcium carbonate; few fine and medium soft masses of gypsum; 38 percent calcium carbonate equivalent; violently effervescent; moderately alkaline (pH 8.4); clear irregular boundary. (10 to 30 centimeters (4 to 12 inches) thick)

Cr--76 to 200 centimeters (30 to 79 inches); soft shale and limestone; 48 percent calcium carbonate equivalent.

TYPE LOCATION: Las Animas County, Colorado; about 16 kilometers (10 miles) north of Andrix, Colorado; about 121 meters (400 feet) south and 579 meters (1,900 feet) east of the southwest corner of sec. 3, T. 31 S., R. 52 W. Sixth Principle Meridian; Buck Canyon, Colorado USGS topographic quadrangle; UTM zone 13 655848 E, 4138484 N; latitude 37 degrees, 22 minutes, 48.1 seconds N. and longitude 103 degrees, 14 minutes, 23 seconds W., NAD 83

RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is moist in some part March through May, intermittently moist June through September, driest December through February.
Moisture regime: ustic moisture regime bordering on aridic
Mean annual soil temperature: 10 to 13 degrees C (50 to 55 degrees F)
Mean summer soil temperature: 20 to 24 degrees C (68 to 74 degrees F)
Calcium carbonate equivalent: 15 to 40 percent
Depth to paralithic contact: 51 to 100 centimeters (20 to 40 inches) to soft shale and limestone
Depth to secondary calcium carbonate: 0 to 5 centimeters (0 to 2 inches)
Thickness of the cambic horizon: 30 to 53 centimeters (12 to 21 inches)
Depth to gypsum accumulations: 51 to 76 centimeters (20 to 30 inches)

Particle-size control section (weighted average):
Clay content: 20 to 35 percent
Sand content: 5 to 35 percent, with less than 15 percent fine and coarser sand
Rock fragments: 0 to 15 percent gravel

A horizon:
Hue: 10YR or 2.5Y
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 or 3
Texture: loam, silt loam
Clay content: 20 to 27 percent
Rock fragments: 0 to 15 percent
Calcium carbonate equivalent: 15 to 30 percent
EC (dS/m): 1 to 3
Reaction: slightly alkaline or moderately alkaline

Bw horizons:
Hue: 10YR or 2.5Y
Value: 5 to 7 dry, 4 or 5 moist
Chroma: 2 to 4
Texture: silt loam, silty clay loam
Clay content: 20 to 35 percent
Rock fragments: 0 to 5 percent
Calcium carbonate equivalent: 15 to 35 percent
EC (dS/m): 1 to 3
Reaction: moderately alkaline or strongly alkaline

Bky horizon:
Hue: 7.5YR to 2.5Y
Value: 6 to 8 dry, 4 to 6 moist
Chroma: 3 to 6
Texture: silt loam, silty clay loam
Clay content: 20 to 35 percent
Rock fragments: 0 to 15 percent
Pararock fragments: 1 to 15 percent
Calcium carbonate equivalent: 20 to 40 percent
EC (dS/m): 1 to 5
Gypsum: 1 to 5 percent
Reaction: slightly alkaline to strongly alkaline

COMPETING SERIES: This is the Buffalo Park series.
Buffalo Park soils: do not have a paralithic contact.

GEOGRAPHIC SETTING:
Parent material: loess mixed with residuum derived from soft shale and limestone
Landform: plains, ridges, hills, pediments
Slopes: 1 to 10 percent
Elevation: 1,219 to 1,981 meters (4,000 to 6,500 feet)
Mean annual temperature: 10 to 12 degrees C (50 to 54 degrees F)
Mean annual precipitation: 356 to 406 millimeters (14 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 Penrose, Ritoazul, and Wiley series. The Penrose soils are less than 20 inches to a lithic contact and are on scarps. The Ritoazul soils average more than 35 percent clay and are on fans and pediments. The Wiley soils are very deep and are on interfluves and plains.

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

USE AND VEGETATION: This soil is used as rangeland; native vegetation is blue grama, western wheatgrass, needlegrass, red threeawn, broom snakeweed, buffalograss, and bottlebrush squirreltail. Loamy Plains R069XY006CO) ecological site

DISTRIBUTION AND EXTENT: Southeastern Colorado; LRR G, MLRA 67B, 69; the soil is of moderate extent.

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

SERIES ESTABLISHED: Las Animas County, Colorado, Las Animas County Area soil survey area, Colorado. The name is coined from a higher moisture phase of the Minnequa series.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:

Series control section: 0 to 101 centimeters (0 to 40 inches)
Particle-size control section: The zone from 25 to 76 centimeters (10 to 30 inches). (Part or all of the Bw1, Bw2, and Bky horizons)
Ochric epipedon: The zone from 0 to 15 centimeters (0 to 6 inches). (A horizons)
Cambic horizon: The zone from 15 t0 53 centimeters (6 to 21 inches). (Bw1 and Bw2 horizons)
Paralithic contact: The contact with shale and soft limestone at 76 centimeters (30 inches). (Cr horizon)
Other features: aridic ustic moisture regime and 15 to 40 percent calcium carbonate equivalent throughout.

Remarks: This soil was part of the Minnequa series but was determined to have a cambic horizon and to have and aridic ustic moisture regime.

The assignment of the cation-exchange activity class is supported by lab sample numbers S87CO-071-010.

7/3013 LAN: This update adds metric measurements, updates the competing series section, the type location, and changes permeability to saturated hydraulic conductivity.

Taxonomic Version: Eleventh Edition, 2010

National Cooperative Soil Survey
U.S.A.