LOCATION MIDCO                   MO

Established Series
Rev. JDG-RLT
12/2021

MIDCO SERIES

Midco series consists of very deep, somewhat excessively drained, cherty soils on flood plains. They formed in recent alluvium derived largely from upland soils underlain by cherty dolomite and sandstone. Slope gradients range from 1 to 4 percent. Mean annual temperature is about 57 degrees F. Mean annual precipitation is about 44 inches.

TAXONOMIC CLASS: Loamy-skeletal, siliceous, superactive, nonacid, mesic Typic Udifluvents

TYPICAL PEDON: Midco cherty loam - on a convex slope of 3 percent in a pine plantation at an elevation of 845 feet. (Colors are for moist soil unless otherwise stated.)

A--0 to 8 inches; dark brown (10YR 3/3) gravelly loam; pale brown (10YR 6/3) dry; weak fine granular structure; friable; many fine and medium roots; 35 percent chert fragments; slightly acid; abrupt wavy boundary. (1 to 10 inches thick)

C1--8 to 17 inches; strong brown (7.5YR 5/6) extremely gravelly sandy loam; massive; friable; common fine and medium roots; 75 percent chert fragments; moderately acid; gradual wavy boundary.

C2--17 to 26 inches; strong brown (7.5YR 5/6) very gravelly sandy loam; massive; friable; common fine roots; 50 percent chert fragments; moderately acid; clear wavy boundary.

C3--26 to 60 inches; strong brown (7.5YR 5/6) extremely gravelly sandy loam; massive; friable; few fine roots; 80 percent chert fragments; moderately acid.

TYPE LOCATION: Shannon County, Missouri; about 4 miles east and 4 miles south of Winona; 690 feet east and 1,980 feet north of the southwest corner, Sec. 13, T. 26 N., R. 3 W; USGS Fremont topographic quadrangle, latitude 36 degrees 55 minutes 10 seconds N. and longitude 91 degrees 14 minutes 14 seconds W., CONUS 27.

RANGE IN CHARACTERISTICS: Solum thickness ranges from 1 to 10 inches. Chert content 3 inches to 2 mm in size ranges from 20 to 80 percent by volume, and approximately 75 percent is 3 inches to 1/4 inch in size. Rock fragments larger than 3 inches range from 5 to 30 percent. The soil ranges from neutral to strongly acid. Some pedons have buried A horizons.

The A horizon has 10YR hue, value of 3 or 4, and chroma of 2 to 4. Texture is gravelly or very gravelly analogues of sandy loam or silt loam.

The C horizon has 10YR or 7.5YR hue, value of 4 to 6, and chroma of 3 to 6. Texture commonly is gravelly to extremely gravelly analogues of loam or sandy loam, but may be extremely gravelly sand or loamy sand in the lower part.

COMPETING SERIES: The Midco series is the only series in the family. The Elsah and Skidmore series are closely related. The Elsah and Skidmore soils have mixed mineralogy. In addition, Skidmore soils have B horizons.

GEOGRAPHIC SETTING: Midco soils occupy narrow strips of flood plains along streams. Slope gradients range from 1 to 4 percent. They formed in recent alluvium derived largely from upland soils underlain by cherty dolomite and sandstone.

GEOGRAPHICALLY ASSOCIATED SOILS: These include the Horsecreek, Newark, Melvin, and Secesh soils. Horsecreek and Secesh soils have argillic horizons and are on terraces. Newark and Melvin soils have more silt and grayer subsoils and are in slightly depressional positions.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained; very low runoff; moderately rapid permeability. The saturated hydraulic conductivity is high.

USE AND VEGETATION: Most areas are used for pasture and hay crops. Native vegetation is shortleaf pine and mixed hardwoods.

DISTRIBUTION AND EXTENT: The Ozark Highland (MLRA 116A) region of southern Missouri. The series is moderately extensive.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: INDIANAPOLIS, INDIANA

SERIES ESTABLISHED: Mark Twain National Forest Area, Missouri (parts of Carter, Oregon, Ripley, and Shannon Counties), 1972.

REMARKS: Diagnostic horizons and features recognized in this series are:
ochric epipedon - the zone from the surface of the soil to a depth of 8 inches (Ap horizon).

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National Cooperative Soil Survey
U.S.A.