LOCATION ORDWAY COEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, mesic Ustic Haplocambids
TYPICAL PEDON: Ordway clay - grassland. (Colors are for dry soil unless otherwise noted.)
A--0 to 4 inches; light olive brown (2.5Y 5/3) light clay, olive brown (2.5Y 4/3) moist; strong very fine granular structure; slightly hard, very friable, sticky, plastic; calcareous; moderately alkaline (pH 8.0); clear smooth boundary. (3 to 6 inches thick)
B--4 to 16 inches; light olive brown (2.5Y 5/4) clay, olive brown (2.5Y 4/4) moist; moderate medium prismatic structure that parts to moderate medium subangular blocks; slightly hard, very friable, sticky, plastic; peds are very hard, firm; few thin glossy patches on some faces of peds; calcareous; moderately alkaline (pH 8.0); gradual wavy boundary. (4 to 27 inches thick)
Bkz--16 to 35 inches; light yellowish brown (2.5Y 6/3) clay, light olive brown (2.5Y 5/3) moist; massive; very hard, firm, sticky, plastic; visible secondary calcium carbonate and much calcium sulfate occurring as concretions, as crystals, in thin seams and streaks, and in finely divided forms; calcium sulfate content approximately 4 percent; calcium carbonate equivalent approximately 10 percent; calcareous; moderately alkaline (pH 8.2); gradual wavy boundary. (10 to 33 inches thick)
2Cr--35 to 50 inches; soft very gypsiferous shale. Gypsum occurring mostly in large crystals and seams in the parent shales. Parent shales are sometimes mottled and streaked with reddish brown colors.
TYPE LOCATION: Crowley County, Colorado; approximately .1 mile north and 50 feet west of the southeast corner of Sec. 24, T. 20 S., R. 57 W.
RANGE IN CHARACTERISTICS:
Depth to calcic horizon: 7 to 26 inches
Depth to the paralithic contact: 20 to 40 inches
Exchangeable sodium: 0 to 15 percent
Particle-size control section (weighted average):
Clay content: 35 to 60 percent
Silt content: 20 to 55 percent
Sand content: 0 to 45 percent
Rock fragments: 0 to about 5 percent
Size: gravel
A horizon:
Hue: 5Y to 7.5YR
Value: 5 to 8 dry, 3 to 7 moist
Chroma: 1 to 4
Reaction: moderately to strongly alkaline (1:5 dilution unbuffered organic dye)
B horizon:
Hue: 5Y to 7.5YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 1 to 6
Reaction: moderately or strongly alkaline (1:5 dilution unbuffered organic dye).
Note: Subhorizons redder than 7.5YR occur in some pedons.
C horizon:
Hue: 5Y through 7.5YR
Gypsum content: 1.5 to about 8 percent
Calcium carbonate accumulation: 3 to 14 percent
Reaction: moderately or strongly alkaline (1:5 dilution unbuffered organic dye)
Note: Subhorizons redder than 7.5YR occur in some pedons
COMPETING SERIES:
Currently there are no competing series.
GEOGRAPHIC SETTING:
Parent Material: moderately thin calcareous gypsiferous and fine to moderately fine textured materials weathered from gypsiferous shales
Landform: nearly level to moderately sloping hills, ridges, and upland plains
Slope: 0 to 12 percent or more
Mean annual temperature: 50 degrees F.
Mean annual precipitation: about 12 inches
Precipitation pattern: peak periods of precipitation in the spring and early summer months
GEOGRAPHICALLY ASSOCIATED SOILS:
These are the
Gaynor and
Pultney soils.
Gaynor soils lack a cambic horizon and contain less than 1.5 percent gypsum by weight.
Pultney soils lack a cambic horizon and have bedrock at depths of less than 20 inches.
DRAINAGE AND PERMEABILITY:
Drainage: well drained
Runoff: medium to rapid
Permeability: moderate to slow
USE AND VEGETATION: Used as grazing land or irrigated or dry cropland. Native vegetation is blue grama, buffalo grass, snakeweed, and cactus.
DISTRIBUTION AND EXTENT: Southeastern Colorado. Series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Arkansas Valley Area, Colorado, 1936.
REMARKS: Last updated by the state 4/73.
Diagnostic horizons and features recognized in this profile are:
Calcic horizon: 16 to 35 inches (Bk horizon)
Paralithic contact: 35 to 50 inches (2Cr horizon)
Updated the classification, competing series and placed in semitab format. LRM 03/01