LOCATION LEBSACK CO+KSEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Pachic Haplustolls
TYPICAL PEDON: Lebsack silty clay loam - cultivated field. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 6 inches; grayish brown (10YR 5/2) silty clay loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure parting to moderate fine granular; slightly hard, very friable; calcareous; moderately alkaline; abrupt smooth boundary. (5 to 8 inches thick)
Bw--6 to 34 inches; grayish brown (10YR 5/2) heavy silty clay loam, very dark grayish brown (10YR 3/2) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; slightly hard, friable; individual peds are hard; few thin patchy clay films on vertical faces of peds; calcareous; moderately alkaline; gradual wavy boundary. (12 to 30 inches thick)
Ck--34 to 60 inches; light gray (2.5Y 6/1) heavy silty clay loam, gray (2.5Y 5/1) moist; massive; hard, friable; visible secondary calcium coarbonate occurring as nodules and in thin seams and streaks; few crystals of calcium sulfate; calcareous; moderately alkaline.
TYPE LOCATION: Logan County, Colorado; approximately 450 feet south and 120 feet east of the N1/4 corner of Sec. 10, T. 6 N., R. 53 W.
RANGE IN CHARACTERISTICS: Mean annual soil temperature is about 50 degrees F. The mollic epipedon ranges from 20 to 40 inches thick and depth to calcareous material ranges from 0 to 6 inches. Organic carbon in the mollic epipedon ranges from .8 to 2 percent and decreases uniformly as depth increases. Cation exchange capacity ranges from approximately 70 to 100 milliequivalents per 100 grams of clay. The particle size control section is typically heavy silty clay loam or light silty clay and has 35 to 50 percent clay, 20 to 50 percent silt, and 10 to 40 percent sand. Rock fragments range from 0 to 15 percent and are typically less than 1 percent.
The A horizon has hue of 2.5Y or 10YR, value of 4 or 5, 2 or 3 moist, and chroma of 1 through 3. Normally the horizon has fine granular structure but has weak subangular blocky structure where plowed. It is soft to slightly hard.
The Bw horizon has hue of 10YR or 2.5Y, value of 4 or 5, 2 or 3 moist, and chroma of 1 or 2. It has moderate to weak prismatic or blocky structure.
The C horizon has hue of 2.5Y or 10YR. It is moderately or strongly alkaline and has 2 to 10 percent calcium carbonate equivalent. Usually there are a few crystals of calcium sulfate scattered throughout this horizon. These soils have few distinct mottles below depth of 40 inches in some pedons.
COMPETING SERIES: This is the Benclare series. This soil lacks calcareous horizons above depths of 24 inches.
GEOGRAPHIC SETTING: Lebsack soils are on alluvial fans, flood plains, or low terraces and have slope gradients of 0 to 5 percent. The soils formed in alluvial sediments. The average annual precipitation is 14 to 16 inches, with peak precipitation occurring during the spring and summer. The mean annual temperature is 47 degrees F, and the mean summer temperature is 68 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Haverson and Nunn soils. Haverson soils have a fine-loamy control section. Nunn soils have an argillic horizon.
DRAINAGE AND PERMEABILITY: Moderately well-drained; slow runoff; slow permeability.
USE AND VEGETATION: These soils are used for native pastureland or they are tilled to adapted crops.
DISTRIBUTION AND EXTENT: Eastern Colorado. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Logan County, Colorado, 1974.