LOCATION CONTRARY MO+KSEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Dystric Eutrudepts
TYPICAL PEDON: Contrary silt loam, on a convex slope of 12 percent, in a pasture. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 20 centimeters (0 to 8 inches); dark brown (10YR 3/3) silt loam, brown (10YR 5/3) dry; weak fine granular structure; friable; many fine roots; few faint very dark grayish brown (10YR 3/2) organic coatings on faces of peds; slightly acid; abrupt smooth boundary. [10 to 23 centimeters (4 to 9 inches) thick]
BE--20 to 36 centimeters (8 to 14 inches); brown (10YR 4/3) silt loam; weak fine subangular blocky structure parting to weak fine granular; friable; common fine roots; few fine faint grayish brown (10YR 5/2) relict iron depletions; few faint very dark grayish brown (10YR 3/2) organic coatings on faces of peds; moderately acid; clear smooth boundary. [0 to 20 centimeters (0 to 8 inches) thick]
Bw1--36 to 53 centimeters (14 to 21 inches); brown (10YR 4/3) silt loam; weak fine subangular blocky structure; friable; few fine roots; few fine prominent strong brown (7.5YR 5/6) relict masses of iron accumulation and common fine distinct grayish brown (2.5Y 5/2) relict iron depletions; few faint very dark grayish brown (10YR 3/2) organic coatings on faces of peds; slightly acid; clear smooth boundary.
Bw2--53 to 69 centimeters (21 to 27 inches); grayish brown (2.5Y 5/2) silt loam; moderate medium subangular blocky structure; friable; few fine roots; common fine prominent strong brown (7.5YR 5/6) relict masses of iron accumulation and distinct gray (10YR 6/1) relict iron depletions; slightly acid; gradual smooth boundary.
Bw3--69 to 81 centimeters (27 to 32 inches); grayish brown (2.5Y 5/2) silt loam; moderate fine and medium subangular blocky structure; friable; many medium distinct brown (10YR 5/3) and common medium prominent yellowish brown (10YR 5/6) relict masses of iron accumulation and common fine distinct gray (10YR 6/1) relict iron depletions; neutral; gradual smooth boundary.
Bw4--81 to 94 centimeters (32 to 37 inches); grayish brown (2.5Y 5/2) silt loam; moderate medium subangular blocky structure; friable; common medium distinct light olive brown (2.5Y 5/4) and many fine prominent strong brown (7.5YR 5/6) relict masses of iron accumulation and common fine distinct gray (10YR 6/1) relict iron depletions; neutral; gradual smooth boundary. [Combined thickness of the Bw horizon is 51 to 122 centimeters (20 to 48 inches).]
BC--94 to 114 centimeters (37 to 45 inches); grayish brown (2.5Y 5/2) silt loam; weak medium subangular blocky structure; friable; few fine distinct light olive brown (2.5Y 5/4) and few fine prominent strong brown (7.5YR 5/6) relict masses of iron accumulation and common fine distinct gray (10YR 6/1) relict iron depletions; slightly acid; gradual smooth boundary. [0 to 25 centimeters (0 to 10 inches) thick]
C--114 to 152 centimeters (45 to 60 inches); grayish brown (2.5Y 5/2) silt loam; massive with some distinct vertical faces; friable; many medium distinct light olive brown (2.5Y 5/4) and few fine prominent strong brown (7.5YR 5/6) relict masses of iron accumulation and common fine distinct light brownish gray (10YR 6/2) relict iron depletions; neutral.
TYPE LOCATION: Major Land Resource Area (MLRA) 107; Buchanan County, Missouri; about 1.5 miles west of Willow Brook; about 335 meters (1,100 feet) west and 375 meters (1,230 feet) north of the center of sec. 33, T. 56 N., R. 35 W.
RANGE IN CHARACTERISTICS:
Depth to carbonates--greater than 102 centimeters (40 inches)
Content of clay in the particle-size control section (weighted average)--20 to 30 percent
Content of sand in the particle-size control section (weighted average)--less than 10 percent
A horizon:
Hue--10YR
Value--2 or 3 moist, 3 to 5 dry
Chroma--2 or 3
Texture--silt loam or silty clay loam
Clay content--20 to 35 percent
Reaction--moderately acid to neutral
BE horizon (when present):
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--1 to 3
Texture--silt loam or silty clay loam
Clay content--20 to 28 percent
Reaction--moderately acid to neutral
Special features--redoximorphic features are considered relict
Bw horizon:
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--1 to 3
Texture--silt loam or silty clay loam
Clay content--20 to 30 percent
Reaction--moderately acid to neutral
Special features--matrix colors and redoximorphic features are considered relict
BC horizon:
Hue--10YR to 2.5Y
Value--5 or 6
Chroma--2 to 4
Texture--silt loam or silty clay loam
Clay content--15 to 30 percent
Reaction--slightly acid to slightly alkaline
Special features--matrix colors and redoximorphic features are considered relict
C horizon:
Hue--10YR to 2.5Y
Value--5 or 6
Chroma--2 to 4
Texture--silt loam
Clay content--15 to 25 percent
Reaction--slightly acid to slightly alkaline
Special features--matrix colors and redoximorphic features are considered relict
COMPETING SERIES: These are the
Drury,
Exette, and
Killduff series.
Drury--have matrix hues of 7.5YR or 10YR in the cambic horizon and do not have redoximorphic features within a depth of 76 centimeters (30 inches)
Exette--are in areas that have a mean annual air temperature range of 7 to 10 degrees C (45 to 50 degrees F)
Killduff--have a clay content of 27 to 35 percent in the particle-size control section
GEOGRAPHIC SETTING:
Parent material--deoxidized and leached Wisconsin age loess
Landform--moderately sloping and strongly sloping side slopes, head slopes, nose slopes, and tops of lowered interfluves on dissected till plains
Slopes--5 to 14 percent
Elevation--243 to 366 meters (800 to 1200 feet) above sea level
Mean annual air temperature--10 to 12 degrees C (50 to 54 degrees F)
Mean annual precipitation--81 to 91 centimeters (32 to 36 inches)
Frost-free period--160 to 180 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Armstrong,
Knox, and
Marshall soils.
Armstrong--are at lower elevations on side slopes and have more clay and sand in the particle-size control section
Knox--are at higher elevations on side slopes and interfluves and have argillic horizons
Marshall--are at higher elevations on side slopes and interfluves, have mollic epipedons and do not have gray colors within a depth of 61 centimeters (24 inches)
DRAINAGE AND PERMEABILITY:
Drainage class--well drained--saturation does not occur within a depth of 1.8 meters (6 feet) during the wettest periods of most years
Saturated hydraulic conductivity--moderately high
Surface runoff potential--medium
USE AND VEGETATION:
Most areas are cultivated. The principal crops are corn, soybeans, small grains, hay, and pasture. The native vegetation is big bluestem, little bluestem, switchgrass, indiangrass, other grasses of the tall grass prairie, and deciduous hardwood trees.
DISTRIBUTION AND EXTENT:
Physiographic Division--Interior Plains
Physiographic Province--Central Lowland
Physiographic section(s)--Dissected till plains
MLRA(s)--Nebraska and Kansas Loess-Drift Hills (106), Iowa and Missouri Deep Loess Hills (107)
LRR M; northwest Missouri and northeastern Kansas
Extent--moderate
MLRA OFFICE RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Buchanan County, Missouri, 1984.
REMARKS:
Particle-size control section--the zone from a depth of 25 to 100 centimeters (10 to 40 inches) (BE, Bw1, Bw2, Bw3, Bw4, and BC horizons);
series control section--the zone from the surface to a depth of 150 centimeters (60 inches) (Ap, BE, Bw1, Bw2, Bw3, Bw4, BC, and C horizons).
Diagnostic horizons and features recognized in this pedon:
ochric epipedon--the zone from the surface to a depth of 20 centimeters (0 to 8 inches) (Ap horizon);
cambic horizon--the zone from a depth of 36 to 94 centimeters (14 to 37 inches) (Bw1, Bw2, Bw3 and Bw4 horizons);
udic soil moisture regime.
Cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.
Taxonomy version--second edition, 1999.
The gray colors described in this pedon were not used in the classification of this soil as they are considered to be inherited from a relict deoxidized and leached weathering zone.