LOCATION LURA MN
Established Series
Rev. HRF-TCJ-AGG
03/2014
LURA SERIES
The Lura series consists of very deep, very poorly drained and poorly drained soils that formed in clayey glacial lacustrine sediments on glacial lake plains, and ground moraines. They have slopes of 0 to 2 percent. Mean annual precipitation is about 711 mm (28 inches). Mean annual air temperature is about 9 degrees C (48 degrees F).
TAXONOMIC CLASS: Fine, smectitic, mesic Cumulic Vertic Epiaquolls
TYPICAL PEDON: Lura silty clay with a concave slope of about 1/4 percent in a depression on a lacustrine-mantled ground moraine in a cultivated field. (Colors are for moist conditions unless otherwise stated.)
Ap--0 to 25 cm (0 to 10 inches); black (N 2/0) silty clay, black (10YR 2/1) dry; moderate very fine subangular blocky structure; friable, plastic, sticky; neutral; abrupt smooth boundary.
A1--25 to 51 cm (10 to 20 inches); black (10YR 2/1) silty clay, very dark gray (10YR 3/1) dry; moderate very fine angular blocky structure; firm, plastic, sticky; neutral; clear smooth boundary.
A2--51 to 66 cm (20 to 26 inches); black (10YR 2/1) clay, very dark gray (10YR 3/1) dry; about 30 percent coarse inclusions of very dark gray (5Y 3/1); weak coarse prismatic structure parting to moderate very fine angular blocky; firm, plastic, sticky; few fine prominent olive (5Y 5/4) Fe concentrations; neutral; clear smooth boundary.
A3--66 to 117 cm (26 to 46 inches); black (5Y 2/1) clay, very dark gray (5Y 3/1) dry; moderate very fine angular blocky structure; firm, plastic, sticky; neutral; clear smooth boundary.
A4--117 to 147 cm (46 to 58 inches); very dark gray (5Y 3/1) silty clay, olive gray (5Y 4/2) dry; moderate very fine angular blocky structure; firm, plastic, sticky; neutral; clear smooth boundary. [Combined thickness of A horizons is 61 to 155 cm (24 to 66 inches).]
Bg--147 to 183 cm (58 to 72 inches); gray (5Y 5/1) silty clay; weak, coarse, subangular blocky structure; firm, plastic, sticky; many fine faint olive gray (5Y 5/2) Fe depletions and common fine distinct olive (5Y 5/4) Fe concentrations; neutral.
TYPE LOCATION: Blue Earth County, Minnesota; about 5 miles west and 4 miles south of Mapleton; 244 m (800 feet) south and 110 m (360 feet) west of center of sec. 26, T. 105 N., R. 27 W., USGS Delavan quadrangle, lat. 43 degrees 52 minutes 02 seconds N., long. 94 degrees 02 minutes 25 seconds W., NAD 27.
RANGE IN CHARACTERISTICS: Typically the depth to free carbonates ranges from 102 to 203 cm (40 to 80 inches), but in the firm substratum phase the depth is as shallow as 51 cm (20 inches). Depth to loam or clay loam glacial till containing 2 to 8 percent of rock fragments ranges from 40 to 120 inches or more. The mollic epipedon ranges from 61 to 168 cm (24 to 66 inches) in thickness. Between depths of 25 and 102 cm (10 and 40 inches), the average content of clay is 45 to 60 percent and the content of sand is less than 15 percent. When undrained, the soil moisture control section is not dry in all parts during the 120 days following the summer solstice.
The A horizon has hue of 10YR to 5Y, value of 2 in the upper part and 3 in the lower part, and chroma of 1 or is N 2/ or N 3/. It has redoximorphic features in some pedons. It is clay, silty clay, or silty clay loam. It is slightly acid or neutral.
A Bg horizon has a matrix with hue of 5Y, value of 4 or 5, and chroma of 1 or 2. It typically is silty clay or clay but the lower part of it in some pedons is clay loam or silty clay loam. It is slightly acid or neutral in the upper part and slightly alkaline in the lower part.
Some pedons have Bkg and Cg horizons. They have a matrix with hue of 2.5Y, 5Y or BGY, value of 5 or 6, and chroma of 1 or 2. It is silty clay loam, silty clay, or clay. It is slightly alkaline or moderately alkaline. A firm till phase of clay loam with a moist bulk density of 1.6 to 1.9 gm/cc is recognized.
COMPETING SERIES: This is the
Danielson and
Swanberger series. Danielson soils do not have saturation in the upper 15 cm (6 inches) of the series control section. Swanberger soils have a Bk horizon within the upper 76 cm (30 inches) of the series control section.
GEOGRAPHIC SETTING: Lura soils primarily are in depressions on glacial lake plains and lacustrine-mantled till plains or ground moraines, but some are along drainageways. They have slopes of 0 to 2 percent. These soils formed primarily in clayey lacustrine sediments of Late Wisconsinan Age. Calcareous loam or clay loam glacial till underlies the lacustrine sediments at depths ranging from 102 to 305 cm (40 inches to 10 feet) or more. Mean annual precipitation ranges from 660 to 813 mm (26 to 32 inches). Mean annual air temperature ranges from 7 to 11 degrees C (45 to 52 degrees F). Frost-free days range from 155 to 200. Elevation above sea level ranges from 213 to 479 m (700 to 1570 feet).
GEOGRAPHICALLY ASSOCIATED SOILS: The
Beauford,
Collinwood,
Guckeen,
Marna, and
Waldorf soils are the main ones. The poorly drained Beauford soils contain more clay than the Lura soils and are associated with them in a few places. The somewhat poorly drained Collinwood and the poorly drained Waldorf soils formed in 122 cm (48 inches) or more of lacustrine sediments and have sola with texture similar to that of the Lura soils. The somewhat poorly drained Guckeen and the poorly drained Marna soils formed in a mantle of clayey lacustrine sediments and have loamy glacial till within depths of 102 cm (40 inches).
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Very poorly drained and poorly drained. Surface runoff is negligible. Saturated hydraulic conductivity, measured in cm per hour is .15 to .51 (.06 to .2 inches). Seasonal high saturation for the undrained phase is at the surface during the months of November to June in normal years for the very poorly drained phase and 15 to 46 cm (.5 feet to 1.5 feet) for the poorly drained phase.
USE AND VEGETATION: Most areas are artificially drained and cultivated. The principal crops are corn and soybeans. Reed canarygrass commonly dominates partially drained pasture. Native vegetation is predominantly wet-site tall prairie species such as prairie cordgrass, switchgrass, big bluestem, wooly sedge, giant goldenrod and Canada goldenrod. The native vegetation on very poorly drained phases is herbaceous marsh species tolerant of excessive wetness such as, cattails, bulrushes, giant burreed, giant reed grass and hydrophytic sedges.
DISTRIBUTION AND EXTENT: MLRA-103, South central Minnesota and possibly north-central Iowa. Moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Faribault County, Minnesota, 1950.
REMARKS: Diagnostic features recognized in this pedon are: mollic epipedon - zone from the surface to 147 cm (58 inches) (Ap and A horizons); cambic horizon - zone from 147 to 152 cm (58 to 60 inches) (Bg horizon). Other features: aquic moisture regime - low chroma below the mollic epipedon; mesic temperature regime.
A firm till substratum is recognized in the geomorphic surface landform of the Kandiyohi till.
ADDITIONAL DATA: Refer to pedon S69MN-7-7 for results of some laboratory analyses of the typical pedon.
National Cooperative Soil Survey
U.S.A.