LOCATION DILTS ND+MTEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, acid, frigid, shallow Aridic Ustorthents
TYPICAL PEDON: Dilts clay - On a 3 percent convex north-facing slope in native grassland. When described the soil was dry throughout. (Colors are for dry soil unless otherwise stated)
A--0 to 5 inches; olive gray (5Y 5/2) clay, olive gray (5Y 4/2) moist; weak medium subangular blocky and moderate fine granular structure; very hard, firm, sticky and very plastic; common fine roots; few small shale chips; medium acid; clear wavy boundary. (3 to 6 inches thick)
C--5 to 19 inches; olive gray (5Y 5/2) channery clay, olive gray (5Y 4/2) moist; weak coarse subangular blocky structure parting to moderate medium and fine platy; extremely hard, very firm, sticky and very plastic; few roots; about 25 percent by volume partly weathered shale channers; strongly acid; gradual boundary. (8 to 14 inches thick)
Cr--19 to 40 inches; gray (5Y 6/1) shale bedrock; common yellow stains on surfaces of plates; very strongly acid.
TYPE LOCATION: Bowman County, North Dakota; about 8 1/2 miles north and 3 1/2 miles east of the southwest corner of North Dakota, 1,455 feet east and 1,220 feet south of the northwest corner, sec. 20, T. 130 N., R. 106 W.
RANGE IN CHARACTERISTICS: The depth to claystone or shale is less than 20 inches. The control section is clay or silty clay and averages about 50 percent clay.
The A horizon has hue of 5Y or 2.5Y, value of 4 to 6 and 3 to 5 moist, and chroma of 1 or 2. It is clay or silty clay and has moderate or strong granular structure. It ranges from neutral to medium acid.
The C horizon has hue of 5Y or 2.5Y, value of 4 to 6 and 4 or 5 moist, and chroma of 1 to 3. It has weak or moderate blocky or platy structure and is strongly or very strongly acid. In some pedons few to many yellow and yellowish brown stains are on the surfaces of the plates, along vertical cracks and faces of peds. The bedrock is strongly or very strongly acid.
COMPETING SERIES: There are no other series in the family. Other competing series are the
Cabbart,
Lisam and
Yawdim
series. These soils are calcareous. In addition, Cabbart soils are loamy and Yawdim soils contain less than 50 percent clay.
GEOGRAPHIC SETTING: The Dilts soils are on nearly level to steep sedimentary plains. Slopes range from 1 to 60 percent. The Dilts soils formed in material weathered from claystone or shale bedrock. Mean annual temperature is 40 to 45 degrees F, and mean annual precipitation is 12 to 16 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Lisam and Yawdim soils on nearby uplands.
DRAINAGE AND PERMEABILITY: Well drained. Medium or rapid runoff. Slow or very slow permeability.
USE AND VEGETATION: Used for rangeland. Native vegetation consists of western wheatgrass, other perennial grasses, a few cedars and sagebrush in places.
DISTRIBUTION AND EXTENT: Southwestern North Dakota and southeastern Montana. The soil is of large extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Bowman County, North Dakota, 1969.
REMARKS: Revised 11/92.
Diagnostic horizons and features recognized in the pedon are: ochric epipedon - the zone from the surface of the soil to a depth of 5 inches (A horizon).