LOCATION MINNEQUA                CO+KS NE SD WY

Established Series
AJC/GB
03/2013

MINNEQUA SERIES

The Minnequa series consists of moderately deep well drained soils that formed in slope alluvium and residuum weathered from chalk, marl, limestone, and limy sedimentary bedrock. Minnequa soils are on hills, cuestas, plains, interfluves, pediments, and ridges. Slopes range from 0 to 30 percent. The mean annual precipitation is about 305 millimeters (12 inches) and the mean annual temperature is about 11 degrees C. (52 degrees F.)

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

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

A--0 to 15 centimeters (0 to 6 inches); grayish brown (10YR 5/2) silt loam, brown (10YR 4/3), moist; moderate fine granular structure; soft, very friable, slightly sticky and slightly plastic; common fine and very fine roots; strongly effervescent, 5 percent calcium carbonate equivalent; slightly alkaline (pH 7.8); clear smooth boundary.. (8 to 18 centimeters (3 to 7 inches) thick)

Bw--15 to 43 centimeters (6 to 17 inches); light yellowish brown (10YR 6/4) silt loam, yellowish brown (10YR 5/4), moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and very fine roots; violently effervescent, 15 percent calcium carbonate equivalent; moderately alkaline (pH 8.2); clear smooth boundary.(15 to 36 centimeters (6 to 14 inches) thick)

Bk--43 to 89 centimeters (17 to 35 inches); very pale brown (10YR 7/3) silty clay loam, light yellowish brown (10YR 6/4), moist; moderate medium subangular blocky structure; moderately hard, friable, slightly sticky, slightly plastic; 8 percent medium distinct irregular carbonate masses in matrix; violently effervescent, 35 percent calcium carbonate equivalent; moderately alkaline (pH 8.4); abrupt wavy boundary. (28 to 46 centimeters (11 to 18 inches) thick)

Cr--89 to 150 centimeters (35 to 60 inches); Niobrara chalk, marl, shale and limy earth with discontinuous thin layers of limestone.

TYPE LOCATION: Pueblo County, Colorado about 14 miles south of Nepesta, Colorado; about 2,450 feet north and 50 feet west of the SE corner of sec. 2, T. 24 S., R. 61 W.; Yellowback Creek USGS Quad; UTM zone 13 571283 E, 4204812 N; latitude 37 degrees, 59 minutes, 17.4 seconds and longitude 104 degrees, 11 minutes, 17.6 seconds; NAD83.

RANGE IN CHARACTERISTICS:
Soil moisture: moist in some part March through May, moist intermittently June through October.
Moisture regime: aridic bordering on ustic.
Average annual soil temperature: 9 to 13 degrees C. (48 to 56 degrees F.)
Average summer soil temperature: 18 to 23 degrees C. (65 to 74 degrees F.)
Depth to uniformly calcareous material: 0 to 8 centimeters (0 to 3 inches)
Depth to visible segregated calcium carbonate: 23 to 51 cm (14 to 20 inches).
Depth to the paralithic contact: 50 to 100 centimeters (20 to 40 inches)
Gypsum content: 0 to 5 percent by weight.
Exchangeable sodium: 0 to 15 percent.
Electrical conductivity: 0.5 to 8 dS/m.
Calcium carbonate equivalent: 5 to 40 percent, generally increasing with depth.

Particle size control section: (weighted average)
Clay content: 20 to 30 percent
Silt content: 40 to 60 percent
Sand content: 5 to 40 percent with less than 15 percent fine or coarser sand
Rock fragment content: 0 to 5 percent and are mainly 7 to 52 mm(1/4 to 2 inches) in diameter

A horizon:
Hue: 5Y to 7.5YR
Value: of 4 through 6 dry, 3 through 5 moist
Chroma: 1 through 3
Texture: silt loam, loam, silty clay loam
Clay content: 18 to 35 percent
Calcium carbonate equivalent: 1 to 10 percent
Reaction: slightly alkaline or moderately alkaline


Bw horizon:
Hue: 5Y to 7.5YR
Value: 6 or 7 dry, 4 through 6 moist
Chroma: 2 through 4
Texture: silt loam, loam, silty clay loam
Clay content: 18 to 35
Reaction: moderately alkaline or strongly alkaline
Calcium carbonate equivalent of the fine earth: 10 to 25 percent

Bk horizon (Bky in some pedons):
Hue: 5Y to 7.5YR
Value: 6 to 8 dry, 5 to 7 moist
Chroma: 2 though 4
Clay content: 15 to 35 percent
Calcium carbonate equivalent: 15 to 40 percent
Gypsum content: 0 to 5 percent
Reaction: moderately alkaline or strongly alkaline

COMPETING SERIES: These are the Manvel(CO) and Willard(NM) series.
Manvel and Willard soils: do not have a paralithic contact at a depth of 50 to 100 cm (20 to 40 inches).

GEOGRAPHIC SETTING:
Landform: hills, cuestas, interfluves, pediments, and ridges
Slopes: range from 0 to 30 percent
Parent material: medium to moderately fine textured, slope alluvium and residuum weathered from chalk, marl, shale and limestone.
Elevation: 1006 to 1981 meters (3,300 to 6,500 feet)
Mean annual precipitation: 254 to 356 millimeters (10 to 14 inches), with peak periods of precipitation in the spring and summer months.
Mean annual temperature: 9 to 12 degrees C. (48 to 54 degrees F.)
Mean summer temperature: 20 to 23 degrees C. (68 to 74 degrees F.)
Frost free season: 125 to 170 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Manvel soils and the Penrose soils.
Penrose soils have a lithic contact at depths of less than 50 centimeters (20 inches)and are on scarps.
Manvel, Minnequa, and Penrose soils often occur in toposequence.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: well drained
Saturated hydraulic conductivity: moderately high to moderately low.

USE AND VEGETATION: Acreage is in rangeland or nonirrigated and irrigated cropland.
Native vegetation is blue grama, buffalograss, western wheatgrass, galleta, cactus, and snakeweed.

DISTRIBUTION AND EXTENT: Southeastern Colorado, western South Dakota, and adjacent parts of Kansas and Nebraska. The series is extensive.

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

SERIES ESTABLISHED: Arkansas Valley Area, Colorado, 1926.

REMARKS: Diagnostic horizons and features in this pedon are:
Ochric epipedon: the zone from 0 to 15 centimeters (0 to 6 inches) (A horizon)
Calcic horizon: the zone from 43 to 89 cm (17 to 35 inches).
Paralithic contact: soft chalk and marl at 89 centimeters (35 inches) (Cr horizon)
Moisture regime: aridic bordering on ustic.

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.

Modified format by LRM in 10/2005 to include metric conversion and change permeability to saturated hydraulic conductivity.

LAN 1/16/2013 The previous classification of calcareous Ustic Torriorthents became obsolete with the Eleventh Edition to Keys to Soil Taxonomy. Based on a field project this update moves the type location from Prowers County to Pueblo County, Colorado and changes the Taxonomic class to Fine-silty, mixed, superactive, mesic Ustic Haplocalcids.

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National Cooperative Soil Survey
U.S.A.