LOCATION LANKIN NDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Pachic Hapludolls
TYPICAL PEDON: Lankin loam - on a plane slope of less than 1 percent under cropland. (Colors are for moist soil unless otherwise stated. Where described the soil was moist throughout.)
A--0 to 11 inches; black (10YR 2/1) loam, very dark gray (10YR 3/1) dry; weak coarse and medium subangular blocky structure parting to weak very fine subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; many roots; many fine pores; neutral; clear smooth boundary. (7 to 14 inches thick)
Bw-11 to 17 inches; very dark brown (10YR 2/2) loam, very dark grayish brown (10YR 3/2) dry; weak coarse prismatic structure parting to weak and moderate medium subangular blocky; hard, friable, slightly sticky and slightly plastic; common roots; common fine pores; neutral; gradual smooth boundary.
Bw2--17 to 21 inches; very dark grayish brown (10YR 3/2) loam, dark grayish brown (10YR 4/2) dry; common fine faint gray (5Y 5/1) and few fine distinct grayish brown (2.5Y 5/2) mottles; weak coarse prismatic structure parting to weak fine subangular blocky; hard, friable, slightly sticky and slightly plastic; few roots; common fine pores; mildly alkaline; clear wavy boundary.
2Bw3--21 to 24 inches; very dark grayish brown (2.5Y 3/2) loam, grayish brown (2.5Y 5/2) dry; weak medium and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; intermittent lenses of sand; few rock fragments 1/8 to 10 inches in diameter; undersides of rock fragments coated with carbonates; few soft masses of carbonates; slight effervescence; mildly alkaline; clear irregular boundary. (Combined Bw horizons 7 to 22 inches thick)
2Bk--24 to 38 inches; light brownish gray (2.5Y 6/2) clay loam, white (2.5Y 8/2) dry; common medium distinct gray (5Y 5/1) and olive brown (2.5Y 4/4) mottles increasing to common fine prominent yellowish brown (10YR 5/4) and olive gray (5Y 5/2) mottles at 34 to 38 inches; weak medium and fine subangular blocky structure; hard, firm, slightly sticky and slightly plastic; 5 percent coarse fragments; violent effervescence; moderately alkaline; gradual wavy boundary. (6 to 20 inches thick)
2C--38 to 60 inches; light olive brown (2.5Y 5/4) clay loam, light yellowish brown (2.5Y 6/4) dry; many medium prominent gray (5Y 5/1) and yellowish brown (10YR 5/6) mottles; massive; very hard, firm, sticky and plastic; 5 percent coarse fragments; common gypsum crystals; slight effervescence; moderately alkaline.
TYPE LOCATION: Walsh County, North Dakota; about 5 1/2 miles east and 4 miles south of Park River; 825 feet east and 110 feet north of southwest corner, sec. 8, T. 156 N., R. 54 W.
RANGE IN CHARACTERISTICS: Typically, a sandy, gravelly, or stony layer is at the contact between the friable loam lacustrine material and the firm loam or clay loam till material. Stony phases are recognized.
The A horizon has hue of 10YR; value of 2, 3, or 4 dry; and chroma of 1.
The Bw horizon has hue of 10YR or 2.5Y; value of 2 to 4 and 3 to 5 dry; and chroma of 1 or 2. It is loam, silt loam, or clay loam. Some pedons do not have a 2Bw horizon.
The 2Bk or Bk horizons have hue of 10YR, 2.5Y, or 5Y, value of 7 or 8 dry and 5 or 6 moist; and chroma of 1 to 4. They are loam or clay loam.
The 2C horizon has hue of 2.5Y, or 5Y, value of 4 to 7 and 6 to 8 dry, and chroma of 1 to 4. It has few to many distinct to prominent mottles. It is firm loam or clay loam. It contains 2 to 10 percent coarse fragments.
COMPETING SERIES These are the Aastad, Darnen, Delette, Lismore, Svea, and Walsh series in the same family and the Emrick, Gardena, Kittson, and Wyard series. Aastad soils have Bw horizons averaging between 28 and 35 percent clay and moderate to strong prismatic structure and have formed entirely in till. Darnen soils do not have mottles with low chroma in the Bw horizon and formed in colluvial sediments. Delette soils do not have carbonates and formed in alluvium or colluvium. Lismore soils formed in silt mantle over friable till. Svea soils formed in friable loam till and do not have mottles with low chroma in the Bw horizon. Walsh soils formed in shaly materials and do not have Bk horizons or mottles with low chroma in the Bw horizon. Emrick soils are coarse-loamy. Gardena soils are coarse-silty. Kittson soils have mollic epipedons less than 16 inches thick. Wyard soils have an aquic moisture regime.
GEOGRAPHIC SETTING: Lankin soils are on level and nearly level glacial lake plains and interbeach areas. Slope gradients range from 0 to 3 percent. The soil formed in lacustrine sediments, 20 to 40 inches thick, over till. The climate is cool and subhumid. Mean annual temperature ranges from 38 to 45 degrees F, and mean annual precipitation from 16 to 22 inches. Most of the moisture comes in the spring and summer.
GEOGRAPHICALY ASSOCIATED SOILS: These are the competing Gardena soils and the Embden, Gilby, Kratka, Tiffany, Tonka, Towner, and Vallers soils. Gardena soils are on nearby areas of the lake plain where the lacustrine sediments are more than 40 inches thick. Embden and Towner soils are on higher lying beach and lake areas where sand deposits are thicker. Gilby soils have calcic horizons within depths of 16 inches. They are in slight depressions adjacent to the Lankin soils. Kratka and Tiffany soils are wetter and are in nearby swales and depressions. In addition, Tiffany soils are coarse-loamy. Tonka and Vallers soils are on lower lying glacial ground moraines and have formed in clay loam glacial till. Tonka soils have albic and argillic horizons. Vallers soils have calcic horizons within depths of 16 inches.
DRAINAGE AND PERMEABILITY: Moderately well drained. Runoff is slow. Permeability is moderately slow. A temporary water table forms on top of the substratum in the spring when the snow melts and after periods of high rainfall.
USE AND VEGETATION: Soils are cropped to spring-seeded small grains, flax, potatoes, and sunflowers. Native vegetation was big bluestem, porcupinegrass, green needlegrass, western wheatgrass, forbs such as maximillian sunflower, and heath aster.
DISTRIBUTION AND EXTENT: Eastern North Dakota, mainly on the western edge of glacial Lake Agassiz. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Walsh County, North Dakota, 1972.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of 24 inches (A, Bwl, Bw2, and Bw3 horizons).