LOCATION CADOMA WY COEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Sodic Ustic Haplocambids
TYPICAL PEDON: Cadoma silty clay loam - rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 10 cm (0 to 4 inches); light brownish gray (2.5Y 6/2) silty clay loam, dark grayish brown (2.5Y 4/2) moist; strong fine granular structure; slightly hard, very friable, very sticky and very plastic; strongly effervescent, calcium carbonate disseminated; strongly alkaline (pH 8.6); gradual smooth boundary. (3 to 6 inches thick)
Bw--10 to 46 cm (4 to 18 inches); light yellowish brown (2.5 6/4) silty clay, olive brown (2.5Y 4/4) moist; moderate coarse prismatic structure parting to moderate medium angular blocky; hard, firm, very sticky and very plastic; few thin glossy patches on faces of peds; strongly effervescent, calcium carbonate as few fine soft masses; very strongly alkaline (pH 9.6); clear smooth boundary. (9 to 18 inches thick)
Bky--46 to 61 cm (18 to 24 inches); light brownish gray (2.5Y 6/2) silty clay; dark grayish brown (2.5Y 4/2) moist; massive; extremely hard, very firm, very sticky and very plastic; strongly effervescent, some visible secondary calcium carbonate and calcium sulfate occurring as soft rounded masses and in small crystals; strongly alkaline (pH 8.8); gradual wavy boundary. (6 to 20 inches thick)
Cr--61 to 150 cm (24 to 60 inches; dark gray, soft calcareous sodic clay shale.
TYPE LOCATION: Johnson County, Wyoming; NW1/4, NW1/4 of sec. 1, T. 46 N., R. 80 W.
RANGE IN CHARACTERISTICS:
Soil moisture: dry more than half the time which occurs about April 21-27; and is dry in all parts of the moisture control section for at least 60 consecutive days from July 15 to October 25 and for at least 90 cumulative days during this period
Depth to calcareous material: 0 to 5 inches.
Depth to the base of the cambic horizon: 12 to 24 inches.
Depth to paralithic content: 20 to 40 inches.
The mean annual soil temperature: 47 to 53 degrees F.
Exchangeable sodium: 15 to 25 percent below the A horizon. Sodium is authegenic.
Calcium carbonate: less than 15 percent by weight.
Gypsum: less than 5 percent by weight.
Particle-size control section (weighted average):
Clay content: 35 to 60 percent
Sand content: 15 to 25 percent
Rock fragments: less than 15 percent by volume.
A horizon:
Hue: 2.5Y or 10YR
Value: 5 to 7 dry, 3 to 5 moist
Chroma: 2 to 4
Reaction: neutral to very strongly alkaline.
Electrical Conductivity: 0 to 4 mmhos/cm
Bw horizon:
Hue: 2.5Y or 10YR
Value: 5 or 6 dry,4 or 5 moist
Chroma: 2 to 5
Texture: silty clay, silty clay loam, clay loam, or clay
Reaction: strongly alkaline or very strongly alkaline
Electrical Conductivity: 4 to 16 mmhos/cm
Bk or Bky horizons:
Hue: 5Y to 10YR
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 2 to 4
Texture: heavy silty clay loam, silty clay, clay loam, or clay
Reaction: strongly alkaline or very strongly alkaline
Electrical Conductivity: 4 to 16 mmhos/cm
Note: This horizon has an accumulation of secondary sodium calcium carbonate and/or gypsum.
Some soils have a C horizon above the paralithic contact. Properties are similar to the Bk or Bky horizons described above.
COMPETING SERIES:
Currently there are no competing series
GEOGRAPHIC SETTING:
Landform: shale uplands
Slope: 1 to 30 percent.
Parent material: fine textured alluvium and residuum weathered from calcareous and gypsiferous shale high in sodium.
Elevation: 3,800 to 6,500 feet.
Average annual precipitation: 10 to 16 inches
Precipitation pattern: over half of the annual precipitation falling in April, May, and June and less than one inch falling in each month of July, August, September, and October.
Frost-free period: 110 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS:
These are the
Bahl,
Samday,
Savageton and
Silhouette soils.
Savageton and Silhouette soils have less than 15 percent exchangeable sodium.
Bahl and Samday soils lack cambic horizons.
Bahl soils have vertic cracking properties.
DRAINAGE AND PERMEABILITY:
Drainage: Well drained
Runoff: medium when the soil is dry and structural cracks are well developed and rapid or very rapid when the soil is saturated
Permeability: slow or very slow
USE AND VEGETATION: Livestock grazing and wildlife habitat. Native vegetation is birdfoot sagebrush, Gardner saltbush, woody aster, Sandberg bluegrass, and western wheatgrass at the type location.
DISTRIBUTION AND EXTENT: Central and eastern Wyoming and eastern Colorado. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Johnson County (Southern Part), Wyoming; 1971.
REMARKS:
Diagnostic horizons and features recognized in this profile are:
Cambic horizon: 10 to 46 cm (4 to 18 inches) (Bw horizon)
Paralithic contact: 61 to 150 cm (24 to 60 inches) (Cr horizon)
Updated the classification, competing series and placed in semitab format. LRM 03/01
This OSD had the classification, pedon description and type location changed but there is no record of why it was changed and no supporting documentation. With this update the classification is being again revised. Original classification was fine, montmorillonitic, mesic Ustollic Camborthids. The revision in 2001 or earlier changed it to a fine, smectitic, mesic Ustic Natrargids. The pedon description changed a B2 horizon with glossy patches to a Bn horizon with clay films and a C1ca to a Bkny but there is no documentation that it was done in the field. This update changes the pedon description back to what closely resembles the original, and changes the classification to the 10th Edition of Keys to Soil Taxonomy equivalent of the original classification. WAW 08/2008