LOCATION EAGLEPOINT MN

Established Series
Rev. PWK-DJP-JJB
09/2013

EAGLEPOINT SERIES

The Eaglepoint series consists of very deep, poorly drained soils that formed in clayey calcareous lacustrine sediments on glacial lake plains. Slope ranges from 0 to 2 percent. Mean annual precipitation is about 575 millimeters. Mean annual air temperature is about 5 degrees C.

TAXONOMIC CLASS: Very-fine, smectitic, frigid Typic Calciaquerts

TYPICAL PEDON: Eaglepoint clay in a slightly convex position in a level lake plain with a slope of less than 1 percent in a cultivated field. (Colors are moist unless otherwise stated)

Ap--0 to 10 inches; black (5Y 2.5/1) clay, very dark gray (5Y 3/1) dry; strong coarse and medium subangular blocky structure; very firm; many very fine roots throughout; few fine and medium calcium carbonate threads and concretions on faces of peds and in pores; strongly effervescent; slightly alkaline; clear wavy boundary. (7 to 12 inches thick)

Bkss1--10 to 22 inches; olive gray (5Y 5/2) clay; moderate thin platy structure parting to strong very fine angular blocky; very firm; common very fine roots in peds and pores; many very fine tubular pores; few distinct intersecting slickensides tilted at less than 45 degrees from horizontal; cracks 1/4 to 3 inches wide and 2 to 4 feet apart filled with Ap material; many carbonate coats throughout; violently effervescent; moderately alkaline; gradual wavy boundary.

Bkss2--22 to 29 inches; olive gray (5Y 5/2) clay; few fine distnct light olive brown (2.5Y 5/4) redoximorphic concentrations; moderate fine prismatic structure parting to strong very fine angular blocky; very firm; common very fine roots in peds and pores; many very fine tubular pores; few distinct intersecting slickensides tilted at less than 60 degrees from horizontal; cracks 1/4 to 2 inches wide and 2 to 4 feet apart filled with Ap material; many carbonate coats throughout; violently effervescent; moderately alkaline; gradual wavy boundary. (Combined Bkss horizons 12 to 40 inches thick)

Bk1--29 to 40 inches; dark grayish brown (2.5Y 4/2) clay; common fine prominent yellowish brown (10YR 5/6) redoximorphic concentrations; moderate fine prismatic structure parting to strong very fine angular blocky; very firm; few very fine roots in peds and pores; common very fine tubular pores; common carbonate coats throughout; strongly effervescent; slightly alkaline; gradual wavy boundary.

Bk2--40 to 48 inches; dark grayish brown (2.5Y 4/2) clay; few fine prominent strong brown (7.5YR 5/6) and common fine prominent yellowish brown (10YR 5/6) redoximorphic concentrations; moderate fine prismatic structure parting to strong very fine angular blocky; very firm; few very fine tubular pores; common carbonate coats throughout; strongly effervescent; moderately alkaline; clear wavy boundary. (Combined Bk horizons 8 to 16 inches thick)

BC--48 to 55 inches; dark grayish brown (2.5Y 4/2) silty clay; common fine prominent yellowish brown (10YR 5/6) and many fine prominent strong brown (7.5YR 5/6) redoximorphic concentrations; moderate medium platy structure parting to moderate fine subangular blocky; firm; few very fine tubular pores; common fine and medium masses of carbonate; strongly effervescent; moderately alkaline; clear wavy boundary. (0 to 10 inches thick)

C--55 to 82 inches; grayish brown (2.5Y 5/2) silty clay; common fine prominent reddish brown (5YR 4/4) and many fine prominent strong brown (7.5YR 5/6) redoximorphic concentrations; medium platy and fine angular blocky soil fragments; very firm; few fine and medium masses of carbonate; slightly effervescent; slightly alkaline.

TYPE LOCATION: Marshall County, Minnesota; about 3 miles west of Stephen; 400 feet west and 1684 feet north of the southeast corner of Sec. 3, T.157N., R.49W.; USGS Stephen, MN quadrangle; lat. 48 degrees, 26 minutes and 50 seconds N. and long. 96 degrees 57 minutes and 25 seconds W, NAD 83.

RANGE IN CHARACTERISTICS: The mollic epipedon ranges from 7 to 12 inches thick. Free carbonates are found in all parts. The particle-size control section averages between 60 and 85 percent clay. These soils do not have rock fragments and contain less than 8 percent sand. The depth to the calcic horizon ranges from 7 to 12 inches.

The A horizon has hue of 10YR, 2.5Y, 5Y or is neutral; value of 1 to 3 moist and 3 to 5 dry; chroma of 0 to 2, moist or dry. Most pedons contain evidence of cracks filled with A material extend into the Bkss horizon. Reaction is slightly alkaline or moderately alkaline. Some pedons have an AB horizon.

The Bkss horizon has hue of 2.5Y or 5Y, value of 3 to 5, and chroma of 1 or 2. Texture is clay or silty clay. Reaction is moderately alkaline in the upper part and slightly alkaline or moderately alkaline in the lower part. Redoximorphic features are few or common and distinct or prominent. The calcium carbonate equivalent ranges from 20 to 40 percent in the upper part and 10 to 30 percent in the lower part.

The Bk and BC horizons have hue of 2.5Y or 5Y, value of 3 or 4, and chroma of 1 or 2. Texture is silty clay or clay. Reaction is slightly or moderately alkaline. Redoximorphic features are common or many and distinct or prominent. Some pedons do not have a BC horizon.

The C horizon has hue of 2.5Y or 5Y, value of 4 or 5, and chroma of 1 to 3. Texture is silty clay or clay. Reaction is slightly alkaline or moderately alkaline. Redoximorphic features are common or many and distinct or prominent.

COMPETING SERIES: There are no other series in the same family.

GEOGRAPHIC SETTING: Eaglepoint soils are in slightly convex or planar areas formed in clayey lacustrine sediments on glacial lake plains. Slopes range from 0 to 2 percent. Mean annual air temperature ranges from 3 to 7 degrees C. Mean annual precipitation ranges from 500 to 650 millimeters. Most of the moisture falls in the spring and summer. Frost-free days range from 110 to 160. Elevation ranges from 230 to 540 meters above sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These include the poorly drained Northcote soils which are mapped in a complex with Eaglepoint soils. Eaglepoint soils occupy slightly higher positions than Northcote and contain a calcic horizon. Minor associated soils are Bearden, Colvin, Fargo, Gunclub, Hegne, and Nielsville which contain less clay.

DRAINAGE AND PERMEABILITY: Poorly drained. Surface runoff is very slow. Saturated hydraulic conductivity measured in inches per hour is .01 to .06. Permeability is very slow. Depth to an apparent seasonal high water table is 0.5 to 1.5 feet at some time from April to July in most years.

USE AND VEGETATION: This soil is used to grow small grains, sugar beets and sunflowers. Native vegetation is mixed prairie grass.

DISTRIBUTION AND EXTENT: Mainly in the Red River Valley in northwestern Minnesota. It is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota

SERIES ESTABLISHED: Marshall County, Minnesota, 1994.

REMARKS: This series replaces the Hegne series when mapped in a complex with Northcote clay.

Diagnostic horizons and features recognized in this pedon are: Mollic epipedon - the zone from the surface to 10 inches (Ap horizon); calcic horizon - the zone from 10 inches to 29 inches (Bkss1 and Bkss2 horizons); aquic suborder based on low chroma in the lower part of the mollic epipedon; very fine family - more than 60 percent clay in the particle-size control section; Vertisol criteria - cracks and slickensides extend through the Bkss horizon.

The MLRA 56 steering committee has recommended classification be revised to the Typic subgroup. The typical site appears to classify as Typic. In addition, the landscape position of Eaglepoint does not warrant a label of somewhat poorly drained. This revision will make the Eaglepoint-Northcote catena analogous to that of Hegne-Fargo.

ADDITIONAL DATA: Soil Interpretation Record is MN0746.

National Cooperative Soil Survey
U.S.A.