LOCATION NUCLA CO+WYEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Torriorthentic Haplustolls
TYPICAL PEDON: Nucla loam on a southwest facing convex slope of 5 percent grassland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 10 centimeters (0 to 4 inches); brown (10YR 5/3) heavy loam, dark brown (10YR 3/3) moist; moderate fine granular structure; slightly hard, friable; neutral (pH 6.7); clear smooth boundary. (8 to 23 centimeters (3 to 9 inches) thick)
A2--10 to 20 centimeters (4 to 8 inches; brown (10YR 5/3) light clay loam, dark brown (10YR 3/3) moist; moderate coarse prismatic structure parting to moderate coarse subangular blocky; slightly hard, friable; slight effervescence; slightly alkaline (pH 7.4); clear wavy boundary. (10 to 25 centimeters (4 to 10 inches) thick)
Bw--20 to 36 centimeters (8 to 14 inches); pale brown (10YR 6/3) light clay loam, brown (10YR 4/3) moist; moderate coarse prismatic structure parting to moderate coarse subangular blocky; slightly hard, friable; strong effervescence; moderately alkaline (pH 8.2); clear wavy boundary. (8 to 23 centimeters (3 to 9 inches) thick)
Ck--36 to 152 centimeters (14 to 60 inches); very pale brown (10YR 7/3) light clay loam, yellowish brown (10YR 5/4) moist; massive; slightly hard, friable; violent effervescence; moderately alkaline (pH 8.2)
TYPE LOCATION: Weld County, Colorado; 488 meters (1,600 feet) north and 716 meters (2,350 feet) east of the SW corner of Sec. 26, T. 11 N., R. 57 W.
RANGE IN CHARACTERISTICS:
These soils have a calcareous cambic horizon, or have a consistent horizon of visible secondary calcium carbonate.
The mollic epipedon has moderate prismatic or blocky structure in the lower part and contains less carbonate than the C horizon.
Depth to uniformly calcareous material ranges from 0 to 25 centimeters (0 to 10 inches), but does not exceed one-half the thickness of the mollic epipedon and is not deeper than the upper boundary of the cambic horizon.
Rock fragments range from 0 to 15 percent and are typically less than 5 percent.
The mean annual soil temperature ranges from 10 to 12 degrees C. (50 to 53 degrees F.)
Some pedons have a paralithic contact at 102 to 152 centimeters (40 to 60 inches).
A horizon:
Hue: 5Y to 7.5YR
Value: 4 or 5, 2 or 3 moist
Chroma: 1 to 3
Reaction: neutral to moderately alkaline
Bw horizon:
Hue: 5Y to 7.5YR
Value: 5 to 7, 4 to 6 moist
Chroma: 2 to 4
Texture: typically light clay loam, but the clay increase is not large enough to qualify as an argillic horizon.
Clay content: 18 to 35 percent
Silt content: 20 to 55 percent
Sand content: 20 to 55 percent with less than 35 percent being fine or coarser sand.
Reaction: moderately alkaline
C horizon:
Hue: 7.5YR to 2.5Y
Reaction: moderately alkaline
COMPETING SERIES: These are the
Connerton(WY),
Hightower(NM),
Ralphston(NM), and
Tarryall(CO) series.
Connerton soils have hue of 5YR or redder in a majority of sub-horizons. Hightower and Tarryall soils have a lithic contact at a depth of less than 40 inches.
Ralphston soils have more than 35 percent fine sand or coarser sand in the particle-size control section.
GEOGRAPHIC SETTING:
Landform: on uplands
Slopes: 0 to 25 percent
Parent material: thick, calcareous, medium and moderately fine textured materials derived predominantly from sedimentary rock
Average annual precipitation: 28 to 36 centimeters (11 to 14 inches) with peak periods of precipitation during the spring and early summer
Mean annual precipitation: up to 43 centimeters (17 inches)
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Ascalon,
Curabith, and
Platner soils.
Ascalon soils have an argillic horizon.
Curabith soils lack a cambic horizon and have a calcic horizon.
Platner soils have a fine textured argillic horizon.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: well drained
Runoff: medium or moderately rapid
Saturated Hydraulic Conductivity: moderately high and high
USE AND VEGETATION: These soils are used principally for rangeland.
There are small areas of irrigated or non-irrigated cropland.
Native vegetation consists mainly of blue grama, snakeweed, prickly pear, and buffalograss.
DISTRIBUTION AND EXTENT: Northeastern Colorado and southeastern Wyoming. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Montrose County, Colorado; 1946.
REMARKS: Diagnostic horizon and features recognized in this pedon are:
Mollic epipedon: 0 to 20 centimeters (0 to 8 inches) (A horizon)
Cambic horizon: with carbonates 20 to 36 centimeters (8 to 14 inches)
Soil last updated by the state 10/93.
Modified format by LRM in 7/2006 to include metric conversion and change permeability to saturated hydraulic conductivity.