LOCATION DRAKNAB WY+NEEstablished Series
TAXONOMIC CLASS: Sandy, mixed, mesic Ustic Torrifluvents
TYPICAL PEDON: Draknab loamy sand-on an east facing, very gently sloping flood plain utilized as rangeland. (Colors are for dry soil unless otherwise stated)
A--0 to 2 inches; yellowish brown (10YR 5/4) loamy sand, brown (10YR 4/3) moist; weak medium and fine granular structure; soft, very friable, nonsticky and nonplastic; strongly effervescent; carbonates disseminated throughout; moderately alkaline (pH 8.0); abrupt smooth boundary. (2 to 6 inches thick)
AC--2 to 8 inches; yellowish brown (10YR 5/4) sandy loam, brown (10YR 4/3) moist; weak medium subangular blocky structure parting to weak medium granular; soft, very friable, nonsticky and nonplastic; slightly effervescent; carbonates disseminated throughouot; moderately alkaline (pH 8.0); clear wavy boundary. (0 to 10 inches thick)
C1--8 to 18 inches; very pale brown (10YR 7/3) sand, yellowish brown (10YR 5/4) moist; single grain; loose, nonsticky and nonplastic; strongly effervescent; carbonates disseminated throughout; moderately alkaline (pH 8.0); clear wavy boundary. (6 to 15 inches thick)
C2--18 to 26 inches; pale brown, loamy coarse sand, dark yellowish brown (10YR 4/4) moist; massive; soft, very friable, nonsticky and nonplastic; strongly effervescent; carbonates disseminated throughout; moderately alkaline (pH 8.2) gradual smooth boundary. (0 to 24 inches thick)
C3--26 to 60 inches; very pale brown (10YR 7/3), stratified coarse sand and loamy sand, pale brown (10YR 6/3) moist; single grain; loose, nonsticky and nonplastic; strongly effervescent; carbonates disseminated thoughout; moderately alkaline (pH 8.0).
TYPE LOCATION: Converse County, Wyoming; 1,900 feet north and 400 feet east of the southwest corner of section 5, T. 40 N., R. 74 W. 43 degrees, 27 minutes, 52 seconds north latitude and 105 degrees, 47 minutes, 7 seconds west longitude.
RANGE IN CHARACTERISTICS: Carbonates occur throughout the profile, but the surface to depths of 10 inches may be free of carbonates, depending upon the source material of the most recent deposition. Organic matter content decreases irregularly with depth. Thin, highly variable textural strata usually occur between depths of 10 and 30 inches. Rock fragments are gravel size and typically are less than 5 percent throughout the profile, but may range to 15 percent. The soil is dry in the moisture control section more than half the time cumulative that the soil temperature at a depth of 20 inches is 41 degrees F. and is never moist in some or all parts for as long as 60 consecutive days when the soil temperature at a depth of 20 inches is 41 degrees F., which occurs about April 21-27, but 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. The mean annual soil temperature is 47 to 52 degrees F. and the soil temperature at a depth of 20 inches is 41 degrees F or more for 175 to 192 days. EC ranges from 0 to 4 mmhos/cm throughout the soil.
The A horizon has hue of 2.5Y, 10YR or 7.5YR, value of 5 to 7 and 3 to 6 moist, and chroma of 2 to 4. Texture is loamy sand, sandy loam, loamy fine sand, fine sandy loam, very fine sandy loam or loam. Reaction is neutral to moderately alkaline.
The C horizon has hue of 2.5Y, 10YR or 7.5YR, value of 5 to 7 and 4 to 7 moist, and chroma of 2 to 4. Texture is loamy sand, loamy coarse sand, coarse sand, loamy fine sand or sand. Manu pedons have stratification of varying thickness and texture, very fine sandy loam and sandy loam being the more common. Reaction ranges from slightly alkaline to strongly alkaline.
COMPETING SERIES: These are the Bankard, Ellicott, Escavada and Kwakina series. Bankard are moist in some or all parts for as long as 60 consecutive days when the soil at 20 inches is 41 degrees or more. Ellicott soils are noncalcareous. Escavada soils are intermittently moist in some parts of the moisture control section from July to October. Kwakina soils are drier in May and June.
GEOGRAPHIC SETTING: Draknab soils are on flood plains and low terraces adjacent to flood plains. Slopes are 0 to 6 percent. The soils formed in coarse textured recent stream alluvium derived originally from sandstone-dominated sedimentary rock. Elevations are 3,500 to 6,000 feet. The average annual precipitation is 12 inches with 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. Precipitation ranges from 10 to 14 inches. The mean annual temperature is about 46 degrees F, but ranges from 44 to 49 degrees F. The frost-free season is about 105 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Clarkelen, Dwyer, Haverdad and Orpha soils. Clarkelen soils have coarse-loamy control sections. Dwyer and Orpha soils have a more uniform texture and organic carbon decreases with depth. In addition, Orpha soils are noncalcareous. Haverdad soils have fine-loamy control sections. Clarkelen and Haverdad are on similar landscape positions and Dwyer and Orpha are on higher landscape positions than the Draknab soils.
DRAINAGE AND PERMEABILITY: Moderately well, well or excessively drained; runoff is negligible or very low depending on slope; rapid permeability. These soils are subject to rare to frequent flooding for very brief or brief periods during prolonged, high intensity storms in the spring and early summer.
USE AND VEGETATION: These soils are dominantly used for grazing. Potential vegetation is slender wheatgrass, needleandthread with scattered cottonwoods.
DISTRIBUTION AND EXTENT: The flood plains and low terraces of streams in the Powder River Basin and adjacent areas of northeastern and north-central Wyoming. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Converse County, Wyoming, Northern Part; 1983.
REMARKS: Diagnostic horizons and features recognized in this pedon are: Ochric epipedon - 0 to 2 inches (A horizon). Usually dry, but moist in some or all parts of the moisture control section for 48 or more days from April 30 to October 30 in most years.
SIR- WY0853
LRR- G