LOCATION BURR MNEstablished Series
TAXONOMIC CLASS: Fine, smectitic, mesic Typic Calciaquolls
TYPICAL PEDON: Burr silty clay loam, on a level slope, at an elevation 1,170 feet, on a glacial lake plain, in a cultivated field. (Colors are for moist soil unless otherwise stated.)
Apy--0 to 7 inches; black (N 2/0) silty clay loam, dark gray (10YR 4/1) dry; weak very fine subangular blocky structure; friable, sticky; common gypsum crystals (16 percent); strongly effervescent; slightly alkaline; abrupt smooth boundary.
A1ky--7 to 13 inches; black (N 2/0) silty clay loam, very dark gray (N 3/0) dry; moderate very fine subangular blocky structure; friable; common gypsum crystals (16 percent); violently effervescent; slightly alkaline; clear wavy boundary.
A2y--13 to 25 inches; mixed very dark gray (N 3/0) and black (N 2/0) silty clay loam, dark gray (10YR 4/1) dry; weak very fine subangular blocky structure; friable; many grayish brown (2.5Y 5/2) gypsum crystals (28 percent); strongly effervescent; slightly alkaline; clear wavy boundary.
A3--25 to 30 inches; very dark gray (N 3/0) silty clay, dark gray (10YR 4/1) dry; weak very fine and fine subangular blocky structure; friable; few gypsum crystals (3 percent); strongly effervescent; slightly alkaline; clear smooth boundary. (20 to 48 inches, combined thickness of A horizons)
A4--30 to 35 inches; dark olive gray (5Y 3/2) silty clay; weak fine subangular blocky structure; friable; few gypsum crystals (2 percent); few fine distinct olive brown (2.5Y 4/4) Fe concentrations; strongly effervescent; slightly alkaline; clear smooth boundary. (0 to 10 inches thick)
Cg1--35 to 45 inches; olive gray (5Y 5/2) silty clay loam; massive; firm; trace of gypsum; few fine manganese oxide concretions; common fine distinct olive brown (2.5Y 4/4) Fe concentrations; strongly effervescent; slightly alkaline; gradual smooth boundary.
Cg2--45 to 60 inches; olive gray (5Y 5/2) clay; massive; firm; trace of gypsum; few 5-25 mm masses of lime; common medium distinct brown (7.5YR 4/4) Fe concentrations; strongly effervescent; slightly alkaline.
TYPE LOCATION: Yellow Medicine County, Minnesota; about 1 mile north and 2 miles east of Canby; about 1,850 feet west and 950 feet north of the southeast corner of section 25, T. 115 N., R. 45 W.; USGS Porter quadrangle; lat. 44 degrees 44 minutes 08 seconds N. and long. 96 degrees 13 minutes 24 seconds W., NAD 83.
RANGE IN CHARACTERISTICS: The mollic epipedon ranges from 20 to 48 inches in thickness. The gypsic horizon begins within depths of 16 inches. Free carbonates are in all parts of the profile. The calcium carbonate equivalent is 5 to l5 percent in the control section. The control section typically has less than l5 percent fine sand and coarser particles. However, some pedons have more than 15 percent of such particles, but most are gypsum crystals. The content of gypsum in the control section typically is 5 to 20 percent with an extreme range to 30 percent. The control section has 35 to 45 percent clay. Bulk density is less than 1.6 g/cc.
The A horizon has hue of 10YR through 5Y, value of 2 or 3, and chroma of 1 or 2. It has weak or moderate granular or subangular blocky structure. It is typically silty clay loam or silty clay. Some pedons have an Ab horizon 6 to 20 inches thick.
Some pedons have an AC horizon or Bg horizon. Properties are similar to the A and C horizon respectively.
The C horizon has hue of 2.5Y or 5Y, value of 4 through 6 and chroma of 3 or less. It is typically silty clay loam or silty clay. Some subhorizons can be clay, clay loam, silt loam or loam.
COMPETING SERIES: This is the Corvuso series. Corvuso soils have a bulk density of greater than 1.6 g/cc in the underlying material.
GEOGRAPHIC SETTING: These soils are nearly level and have plane or slightly concave slopes. These soils are on glacial lake plains. They formed in calcareous clayey, glacial lacustrine sediments. The climate is subhumid continental with warm summers and cold winters. Mean annual air temperature is 45 to 48 degrees F, and mean annual precipitation is 22 to 26 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Calco soils on similar landscapes and Du Page soils on slightly higher landscapes than Burr soils. Both of these soils lack the high content of gypsum in the solum. Du Page soils are better drained and are adjacent to the streams that cross lake plains.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Poorly drained. Seasonal high saturation occurs as high as 6 inches during the months of April to June in normal years. Runoff is low. Saturated hydraulic conductivity, expressed in inches per hour, is 0.2 to 0.6. Occasional flooding from overland flow may occur in some areas.
USE AND VEGETATION: Most areas are cropped to corn, soybeans, and small grains. Native vegetation was a mixture of water-tolerant tall grass prairie species.
DISTRIBUTION AND EXTENT: Southwestern Minnesota. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Yellow Medicine County, Minnesota, 1979.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from o to 35 inches (Apy, A1ky, A2y, A3 and A4 horizons); Gypsic horizon - the zone from 0 to 25 inches; Aquic moisture regime.
These soils were included with Oldham and Colvin soils in a few places in the past.
ADDITIONAL DATA: For results of some laboratory analysis refer to MN. Agr. Exp. Sta. Control file Code Nos. 2518 for some data on the typical pedon, and 1138, 1144, and 1944 for data on three additional pedons.