LOCATION EKALAKA ND+SDEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Typic Natrustolls
TYPICAL PEDON: Ekalaka fine sandy loam - on a west-facing convex slope of 4 percent in native grass. (Colors are for dry soil unless otherwise stated. Where described the soil was dry throughout.)
A--0 to 6 inches; dark grayish brown (10YR 4/2) fine sandy loam, very dark brown (10YR 2/2) moist; weak fine granular structure; soft, very friable, slightly sticky and nonplastic; few medium and common fine and very fine roots throughout; strongly acid; clear smooth boundary. (Combined A horizons 5 to 13 inches thick)
E--6 to 12 inches; light brownish gray (2.5Y 6/2) fine sandy loam, dark grayish brown (2.5Y 4/2) moist; weak very thin platy structure; soft, very friable, nonsticky and nonplastic; many very fine roots; slightly acid; abrupt wavy boundary. (0 to 7 inches thick)
Btn--12 to 17 inches; dark grayish brown (10YR 4/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; strong coarse columnar structure parting to strong medium angular blocky; extremely hard, firm, nonsticky and slightly plastic; common fine and many very fine roots between peds; clay bridging between sand grains and light gray (10YR 7/2) sand coats on faces of peds dark grayish brown (10YR 4/2) moist; neutral; gradual wavy boundary. (3 to 18 inches thick)
Bz1--17 to 21 inches; grayish brown (10YR 5/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; moderate medium prismatic structure parting to moderate medium angular blocky; very hard, friable, nonsticky and slightly plastic; common very fine roots between peds; many threads and masses of salt; slight effervescence; slightly alkaline; gradual wavy boundary.
Bz2--21 to 25 inches; pale brown (10YR 6/3) loamy fine sand, dark grayish brown (10YR 4/2) moist; weak coarse prismatic structure parting to weak medium subangular blocky; very hard, friable, nonsticky and nonplastic; few very fine roots; few masses of salt; slight effervescence; slightly alkaline; clear wavy boundary. (Combined Bz horizons 0 to 22 inches thick)
BCz--25 to 33 inches; grayish brown (2.5Y 5/2) fine sandy loam, dark grayish brown (2.5Y 4/2) moist; massive; very hard, firm, nonsticky and nonplastic; few very fine roots throughout; few salt masses; many coarse yellowish brown (10YR 5/6) and dark yellowish brown (10YR 4/4) masses of manganese; slight effervescence; slightly alkaline; gradual wavy boundary.
C--33 to 60 inches; light gray (5Y 7/2) stratified fine sandy loam, loamy sand and sand, olive gray (5Y 4/2) moist; massive; hard, friable, nonsticky and nonplastic; few very fine roots throughout; moderately alkaline.
TYPE LOCATION: Grant County, North Dakota; 2,110 feet east and 1,300 feet north of the southwest corner of sec. 15, T. 133 N., R. 83 W.
RANGE IN CHARACTERISTICS: The thickness of the surface layers ranges from 7 to 20 inches and is the same as the depth to the Btn horizon. The mollic epipedon ranges in thickness from 7 to 25 inches.
The A horizon has hue of 10YR or 2.5Y, value of 4 or 5 and 2 or 3 moist, and chroma of 2 or 3. It is fine sandy loam, loamy fine sand, very fine sandy loam or sandy loam. It is strongly acid to moderately alkaline.
The E horizon has hue of 10YR or 2.5Y, value of 5 to 7 and 3 to 5 moist, and chroma of 1 to 3. It is loamy fine sand, fine sandy loam or very fine sandy loam. It has platy structure. It is strongly acid to moderately alkaline. Some tilled pedons do not have an E horizon.
The Btn horizon has hue of 10YR, 2.5Y, or 5Y, value of 4 to 6 and 3 to 5 moist, and chroma of 2 to 4. It is sandy loam, fine sandy loam or loam. It has strong grades of columnar or prismatic structure, which typically part to angular or subangular blocky. It is neutral to strongly alkaline. Some pedons have Btk or Btz horizons. In these horizons carbonates or salts are in few or common, fine or medium accumulations in the interior of the prisms or columns. Some pedons have Bky or Bkyz horizons.
The Bz horizon has hue of 10YR, 2.5Y or 5Y, value of 5 to 7 and 3 to 6 moist, and chroma of 2 to 4. It is fine sandy loam, loamy fine sand, fine sand or sandy loam. It is slightly alkaline to strongly alkaline. Some pedons do not have a BC horizon.
The C horizon has hue of 2.5Y or 5Y, value of 5 to 7 and 4 to 6 moist, and chroma of 2 to 4. It is stratified fine sandy loam, loamy fine sand, fine sand or sandy loam. It is slightly alkaline to strongly alkaline. Typically the soil does not have fine grained soft sandstone within a depth of 60 inches, but it is at depths of 40 to 60 inches in some pedons.
COMPETING SERIES: These are the Desart, Evridge and Portal series in the same family. Desart soils have combined A and E horizons ranging from 20 to 30 inches in thickness over the Btn horizon. Evridge soils are moderately deep to soft sandstone. Portal soils do not have stratified fine sand to fine sandy loam in the substratum and formed in glaciofluvial sediments.
GEOGRAPHIC SETTING: Ekalaka soils are on level to strongly sloping terraces, fans and uplands. Slope gradients range from 0 to 15 percent. The soils formed in stratified alkaline alluvium or residuum from soft sandstone. The climate is cool, semi-arid. The mean annual temperature ranges from 39 to 45 degrees F, and the mean annual precipitation from 13 to 18 inches. Most of the moisture falls in the spring and summer.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Desart soils and the Daglum, Ladner, Parshall, Rhoades, Sorum, Tally and Vebar soils. Desart and Ladner soils are in a complex with Ekalaka soils in some areas. Ladner soils do not have a mollic epipedon. Daglum, Rhoades and Sorum soils are on nearby terraces or uplands. Daglum and Rhoades soils are fine and Sorum soils are fine-loamy. In addition Rhoades soils have visible salts or gypsum within a depth of 16 inches. Parshall and Tally soils are on nearby upland terraces and fans and do not have natric horizons. Vebar soils are on uplands and do not have natric horizons and, in addition, have soft sandstone within depths of 40 inches.
DRAINAGE AND PERMEABILITY: Well drained or moderately well drained. Runoff is slow or medium. Permeability is slow.
USE AND VEGETATION: Some areas are cropped to small grains and feed crops, and other areas used for pasture and range. Native vegetation was needleandthread, prairie sandreed, prairie junegrass, upland sedges, blue grama, and a variety of forbs.
DISTRIBUTION AND EXTENT: Southwestern North Dakota and northwestern South Dakota. The soil is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Bowman County, North Dakota, 1969.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of 7 inches (after mixing), (A and E horizons); albic horizon- the zone from 6 to 12 inches (E horizon); natric horizon - the zone from 12 to 17 inches (Btn horizon).
ADDITIONAL DATA: Type location sample number S81ND037-10(1-7). Other sample numbers S64NDak-6-6 and S64NDak-6-7, Bowman County, North Dakota.