LOCATION OGBORN MO

Tentative Series
JDC
06/2012

OGBORN SERIES

The Ogborn series consists of very deep, somewhat poorly drained soils that formed in loess over clayey residuum from dolomite. The Ogborn soils are on divides and interfluves. Slopes range from 1 to 5 percent. Mean annual temperature is 15 degrees C, and the mean annual precipitation is 1055 mm.

TAXONOMIC CLASS: Fine, mixed, active, mesic Aeric Albaqualfs

TYPICAL PEDON: Ogborn silt loam on a linear slope of 3 percent, in a cultivated field, at an elevation of 227 meters. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 15 cm; brown (10YR 4/3) silt loam; moderate very fine and fine granular structure; friable; common yellowish red (5YR 5/6) masses of oxidized iron; common black (10YR 2/1) iron-manganese concretions; slightly acid; clear smooth boundary.

AB--15 to 43 cm; yellowish brown (10YR 5/4) silt loam; moderate very fine and fine subangular blocky structure; friable; very few light gray (10YR 7/2) silt coats; common yellowish red (5YR 5/6) masses of oxidized iron; slightly acid; abrupt smooth boundary.

2Bt1--43 to 64 cm; brown (10YR 5/3) silty clay; strong medium prismatic structure parting to moderate very fine and fine subangular blocky; firm; few distinct dark yellowish brown (10YR 4/4) clay films on all faces of peds and few light gray (10YR 7/2) silt coats; common yellowish brown (10YR 5/6) masses of oxidized iron; common black (10YR 2/1) iron-manganese masses; extremely acid; gradual wavy boundary.

2Bt2--64 to 107 cm; brown (10YR 5/3) silty clay loam; strong medium prismatic structure parting to moderate very fine and fine subangular blocky; firm; few distinct dark yellowish brown (10YR 4/4) clay films on all faces of peds and few light gray (10YR 7/2) silt coats; many strong brown (7.5YR 5/6) masses of oxidized iron; many grayish brown (10YR 5/2) iron depletions; common black (10YR 2/1) iron-manganese masses; very strongly acid; gradual wavy boundary.

2Btg1--107 to 130 cm; 60 percent grayish brown (10YR 5/2) and 40 percent yellowish brown (10YR 5/4) silt loam; moderate medium subangular blocky structure; firm; few faint dark grayish brown (10YR 4/2) clay films on all faces of peds and few light gray (10YR 7/2) silt coats; many strong brown (7.5YR 5/6) masses of oxidized iron; common black (10YR 2/1) iron-manganese masses; 1 percent chert gravel; very strongly acid; clear wavy boundary.

2Btg2--130 to 168 cm; 80 percent grayish brown (10YR 5/2) and 20 percent yellowish brown (10YR 5/4) silty clay loam; moderate medium subangular blocky structure; firm; few faint dark grayish brown (10YR 4/2) clay films on all faces of peds and few light gray (10YR 7/2) silt coats; many strong brown (7.5YR 5/6) masses of oxidized iron; common black (10YR 2/1) iron-manganese masses; 1 percent chert gravel; very strongly acid; clear wavy boundary.

2Btg3--168 to 211 cm; 60 percent yellowish brown (10YR 5/6) and 40 percent gray (10YR 5/1) silty clay loam; strong very fine angular blocky structure; firm; few faint dark grayish brown (10YR 4/2) clay films on all faces of peds; many strong brown (7.5YR 5/6) masses of oxidized iron; common black (10YR 2/1) iron-manganese masses; strongly acid.

TYPE LOCATION: Bollinger County, Missouri; in a cultivated field 200 feet south and 500 feet west of the northeast corner of section 29, T. 33 N., R. 10 E.; USGS Sedgewickville, Missouri topographic quadrangle; lat. 37 degrees, 31 minutes, 26.4 seconds N and long. 89 degrees, 58 minutes, 25.0 seconds W., NAD83. Elevation is 750 feet.

RANGE IN CHARACTERISTICS:
Depth to the top of the argillic horizon is 36 to 66 cm.
Clay content of the particle-size control section (weighted average)--35 to 50 percent.
Rock fragments--(pebbles) range from 0 to 3 percent in the 2Btg horizons.

Ap horizon:
Hue--10YR
Value--4 or 5
Chroma--2 or 3, oxide segregated colors in the matrix can be as high as 7
Texture--silt loam
Reaction--5.1 to 6.0, unless limed
Thickness--10 to 25 cm

AB or E horizon:
Hue--10YR or 2.5Y
Value--5 or 6
Chroma--2 to 4, oxide segregated colors in the matrix can be as high as 7
Texture--silt loam
Reaction--5.1 to 6.0, unless limed
Thickness--12 to 30 cm

2Bt or 2Bt/E horizon:
Hue--10YR or 2.5Y
Value--4 to 6
Chroma--2 or 3, oxide segregated colors in the matrix can be as high as 7
Texture--silty clay loam or silty clay
Reaction--3.5 to 5.5
Thickness--30 to 56 cm

2Btg or C horizon:
Hue--10YR to 5Y
Value--4 to 6
Chroma--1 or 2, oxide segregated colors in the matrix can be as high as 7
Texture--silt loam or silty clay loam
Reaction--3.5 to 5.5
Thickness--more than 30 cm

COMPETING SERIES: Belews Lake. Belews Lake soils formed in alluvium on stream terraces within the Triassic Basin of the Southern Piedmont.

GEOGRAPHIC SETTING: Ogborn soils are on divides in the southeastern Ozarks. They formed in loess over clayey residuum from dolomite. Slopes range from 1 to 5 percent. Mean annual temperature ranges from 12 to 16 degrees C., and the mean annual precipitation ranges from 965 to 1145 mm. Frost-free days range from 175 to 245.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Fourche, Nicholson, and Wrengart soils. The moderately well drained Fourche, Nicholson, and Wrengart soils have a fine-silty control section and are on slightly more convex positions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained, moderate saturated hydraulic conductivity in the upper part of the solum and moderately slow in the lower part. In undrained areas, an intermittent, apparent high water table is at 1.25 to 2.0 foot below the surface from December through April in most years.

USE AND VEGETATION: Most areas are used for hay and pasture, and a few areas are in woodland or brushy idle pasture. Native vegetation is mixed deciduous, hardwood forest.

DISTRIBUTION AND EXTENT: Southeastern Ozarks, Missouri; MLRA-116C and 116A. The acreage is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia.

SERIES PROPOSED: Bollinger County, Missouri, 2012.

REMARKS: Diagnostic horizons and features in this pedon include:
Ochric epipedon - from a depth of 0 to 43 cm (Ap, AB horizons).
Argillic horizon - from a depth of 43 to 211 cm (2Bt1, 2Bt2, 2Btg1, 2Btg2, 2Btg3 horizons).
Redoximorphic features - from a depth of 0 to 211 cm (Ap, AB, 2Bt1, 2Bt2, 2Btg1, 2Btg2, 2Btg3 horizons).

ADDITIONAL DATA: Missouri Soil Characterization Lab number M0001702. These soils were previously mapped as a taxajunct to the Auxvasse series.

National Cooperative Soil Survey
U.S.A.