LOCATION BORDEAUX WYEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Torriorthentic Haplustolls
TYPICAL PEDON: Bordeaux fine sandy ioam
Al--0 to 8 inches; grayish-brown (lOYR 5/2) fine sandy loam, very dark grayish-brown (lOYR 3/2) moist; moderate very fine granular structure; soft dry, very friable moist; noncalcareous, pH 7.6; clear smooth boundary. 6 to 15 inches thick.
Clca--8 to 18 inches; grayish-brown (lOYR 5/2) fine sandy loam, very dark grayish-brown (lOYR 4/2) moist; weak coarse prismatic structure breaking to weak medium subangular blocks; slightly hard dry, very friable moist; a weak ca horizon with some visible calcium carbonate occurring mostly as small seams; calcareous, pH 8.2; abrupt smooth boundary. 6 to 18 inches thick.
II C2ca--18 to 60 inches; pale brown (lOYR 6/3) loam, brown (lOYR 5/3) moist; massive or very weak coarse subangular blocky structure; slightly hard dry, very friable moist; S percent Brule; a weak ca horizon w;th visible calcium carbonate occurring as concretions, and in thin seams and streaks; calcareous, pH 8.4. Several feet thick.
TYPE LOCATION: 90 feet north and 90 feet west of the south quarter corner sec 16, T. 24 N., R. 68 W,, Goshen County, Wyoming.
RANGE IN CHARACTERISTICS: Color of the Al horizon may range in hue from 2.5Y to IOYR, in chroma from 1.5 to 3, and in value from 4 to 5.5 dry and 2 to 3.5 moist. Hue of the Cca horizon ranges from 2.5Y to lOYR. Reaction of the A horizon ranges from calcareous to noncalcareous with pH ranging from 7.6 to 8.2. Reaction of the Cca horizon ranges from pH 8.0 to pH 8.6. Calcium carbonate equivalent of the strongest part of the Cca horizon is typically 5 to 6 percent, but may range from 2 to 12 percent. Texture of the upper part of the control section is typically a fine sandy loam with clay ranging from 5 to 18 percent, silt from 5 to 35 percent, and sand from 50 to 80 percent, but excluding loamy very fine sand or textures having less than 35 percent fine sand or coarser. The lower part of the control section is typically a loam or very fine sandy loam with clay ranging from 10 to 25 percent, silt from 25 to 6O percent, and sand from 20 to 60 percent, but excluding any texture having more than 35 percent fine sand or coarser. Materials like those described for the lower part of the control section must constitute at least 1/4 of the control section, and there must be some inf1uence from Brule sediments in the upper portion as well. Organic carbon content of the mollic epipedon ranges from 0.6 percent to 2 percent decreasing uniformly with depth. E.S P. is usually less than 3 percent throughout, but may increase slightly with depth. Conductivity is usually less than 1 millimho in the upper control section, but may exceed 1 mlllimho below the lithologic discontinuity. The soil is usually base saturated with exchangeable sodium and potassium increasing with depth and exceeding exchangeable hydrogen. Base exchange capacity/clay ratio is greater than 1 in the upper control section and exceeds 1.5 in the lower part. Content of ash exceeds amounts definitive of Andic subgroups. Thickness of the mollic epipedon ranges from 6 to 15 inches, depth to calcareous material ranges from O to 20 inches, and there should
be no bedrock above 40 inches in these soils.
COMPETING SERIES: These include Esquatzel, Powder, and Mitchell series. They differ from the Esquatzel and Powder series in having polylithologic parent materials with sandier upper control sections. They differ from the Mitchell series in having a mollic epipedon, in having a polylithoiogic type of parent material, and in having coarser textures in the upper control section.
SETTING: The Bordeaux series occurs on gently to moderately sloping alluvial fans below exposures of Brule and fine-gra ined sandstone. Slopes range from 2 to lO percent. They are developing in polylithologic parent materials in which the upper material is a fine sandy loam derived either as alluvium or aeolian sediments, while the lower part of the regolith is alluvial fan sediments derived principally from Brule bedrock. At the type location the average annual precipitation is 16 inches, 10 to 11 inches of which falls during the period April through August. The average annual soil temperature is 51 degrees F., and the average summer soil temperature is 71 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the Bayard, Otero, and Keota series. They differ from the Bayard series in having finer textured lower control sections, in having polylithologic parent materials, and in having portions of the regolith strongly influenced by sediments containing volcanic ash. They differ from the Otero series in having a mollic epipedon, in having a polylithologic type of parent material in which the lower part of the control section is finer textured, and in containing a considerable amount of sediment which contain volcanic ash. They differ from the Keota series in having no bedrock above 40 inches, in having polylithologic parent materials in which the upper portion of the control section is coarser textured, and in having a mollic epipedon.
DRAINAGE AND PERMEABILITY: Well-drained. Runoff is slow to medium, and permeability is medium to rapid.
USE AND VEGETATION: These soils are used principally as rangeland, but may be tilled locally. Native vegetation includes blue grama, western wheat, and cactus.
DISTRIBUTION AND EXTENT: Present known distribution limited to southeastern Wyoming. The series is of limited extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Platte County, Wyoming, 1926.
REMARKS: Exact source of series name is unknown, but it is presumed to be a local place name in Platte County, Wyoming.
OSED scanned by NSSQA. Last revised by state on 1/65.