LOCATION MCKEEN NDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, frigid Typic Fluvaquents
TYPICAL PEDON: Mckeen loam - on a level slope under grassland. When described the soil was moist from 12 to 60 inches. (Colors are for moist soil unless otherwise stated)
A--0 to 2 inches; very dark grayish brown (10YR 3/2) loam, grayish brown (10YR 5/2) dry; moderate very fine and fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and common fine roots; common very fine pores; very slight effervescence; slightly alkaline; clear smooth boundary. (2 to 6 inches thick)
C--2 to 12 inches; stratified dark grayish brown (2.5Y 4/2) loam, light brownish gray (2.5Y 6/2) dry; many fine faint grayish brown (2.5Y 5/2) redox depletions and many fine prominent yellowish brown (10YR 5/8) redox concentrations; moderate medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and few fine roots; common very fine pores; slight effervescence; slightly alkaline; abrupt smooth boundary.
Ab--12 to 15 inches; very dark grayish brown (2.5Y 3/2) silty clay, grayish brown (2.5Y 5/2) dry; few fine prominent yellowish brown (10YR 5/8) redox concentrations; strong fine subangular blocky structure; hard, firm, very sticky and very plastic; few very fine and fine roots; few very fine pores; slight effervescence; slightly alkaline; clear smooth boundary. (0 to 7 inches thick)
Cg1--15 to 23 inches; stratified olive gray (5Y 4/2) silty clay loam, olive gray (5Y 5/2) dry; few fine prominent dark yellowish brown (10YR 4/4) redox concentrations; massive; hard, firm, sticky and plastic; few very fine and fine roots; few very fine pores; slight effervescence; slightly alkaline; clear smooth boundary.
Cg2--23 to 45 inches; stratified dark olive gray (5Y 3/2) and olive gray (5Y 4/2) loam, olive gray (5Y 5/2) and light olive gray (5Y 6/2) dry; common fine distinct gray (5Y 5/1) redox depletions and common fine prominent dark yellowish brown (10YR 4/4) redox concentrations; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; few very fine pores; slight effervescence; slightly alkaline; clear smooth boundary.
Cg3--45 to 54 inches; stratified olive gray (5Y 4/2) loam, olive gray (5Y 5/2) dry; many fine faint gray (5Y 5/1) redox depletions and many fine prominent dark yellowish brown (10YR 4/4) redox concentrations; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; few very fine pore; slight effervescence; slightly alkaline; clear smooth boundary.
Cg4--54 to 60 inches; stratified olive gray (5Y 4/2) loamy fine sand, light olive gray (5Y 6/2) dry; common fine faint gray (5Y 5/1) redox depletions and common fine prominent dark yellowish brown (10YR 4/4) redox concentrations; massive; soft, very friable, nonsticky and nonplastic; few very fine roots; few very fine pores; very slight effervescence; slightly alkaline.
TYPE LOCATION: Morton County, North Dakota; about 16 miles southeast of Mandan; 80 feet south and 230 feet east of the northwest corner, sec. 32, T. 137 N., R. 79 W.
RANGE IN CHARACTERISTICS: Depth to carbonates ranges form 0 to 6 inches. The 10-to 40-inch control section typically is stratified with loam, silt loam, silty clay loam or clay loam textures averaging between 18 to 30 percent clay and more than 15 percent fine and coarser sand. Thin strata of coarser or finer textures are common. Some pedons have an O horizon.
The A horizon has hue of 10YR or 2.5Y, value of 2 to 4 and 3 to 6 dry, and chroma of 1 or 2. It is loam, silt loam, silty clay loam or very fine sandy loam and less commonly fine sandy loam or silty clay. It is neutral or slightly alkaline.
The C and Cg horizons have hue of 2.5Y or 5Y, value of 3 to 6 and 4 to 7 dry, chroma of 1 or 2. They typically have redox depletions and concentrations. Textures are loam, silt loam, silty clay loam or clay loam. Coarser or finer textures occur as thin strata or are below a depth of 40 inches. The C and Cg horizons are slightly alkaline or moderately alkaline.
COMPETING SERIES: These are the Bigsandy and Hagga series. Bigsandy soils have an EC of 4 mmhos/cm or more at depths as shallow as 2 inches. Hagga soils occur at elevations over 5,800 feet.
GEOGRAPHIC SETTING: Mckeen soils are on low flats on the floodplain of the Missouri River. Slope gradients are 0 to 1 percent. The soils formed in stratified, loamy alluvium. They are artificially saturated due to dams on the Missouri River. The mean annual temperature ranges from 39 to 45 degrees F and the mean annual precipitation ranges from 13 to 18 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Banks, Havrelon, Lallie and Lohler soils. None of these soil, except Lallie, have an aquic moisture regime. In addition, Banks soils are sandy and Lallie and Lohler soils are fine. Banks soils are on levees adjacent to the river. Havrelon and Lohler soils are on higher lying positions on the floodplain. Lallie soils are in oxbows.
DRAINAGE AND PERMEABILITY: Very poorly drained. Runoff is slow or ponded. Permeability is moderate. A seasonal high water table is at the surface to a depth of 1 foot at some time during the period of January through December. Ponded phases have a seasonal high water table that ranges from 3 feet above the surface to a depth of 1 foot at some time during the period of January through December. The water table depth and duration is affected by fluctuations in the levels of Lake's Oahe and Sakakawea.
USE AND VEGETATION: Used for hayland and wildlife. Native vegetation is reed canary grass, western wheat grass and willow trees.
DISTRIBUTION AND EXTENT: Central and western North Dakota adjacent to the Missouri River. The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Morton County, North Dakota, 1998.
REMARKS: Diagnostic horizons and features recognized in this pedon are: ochric epipedon - the zone from the surface of the soil to a depth of two inches (A horizon); aquic suborder criteria - chroma of 2 and redox concentrations in 40 to 50 cm layer (Cg1 horizon); irregular decrease in organic carbon with depth - indicated by stratifications within C horizon layers and color and texture differences between C horizons.
The wetness of this series is a result of waters of Lake's Oahe and Sakakawea being backed up due to dams on the Missouri River. These soils would have been the Havrelon series prior to the dams on the river. These soils were most probably mapped as Havrelon or variants of Havrelon and Neche in Emmons and Burleigh Counties.