LOCATION MODALE IA+MO NE SDEstablished Series
TAXONOMIC CLASS: Coarse-silty over clayey, mixed, superactive, calcareous, mesic Aquic Udifluvents
TYPICAL PEDON: Modale silt loam, on a slope of about 1 percent, in a cultivated field, at an elevation of 995 feet above sea level. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 7 inches, very dark grayish brown (2.5Y 3/2) silt loam, grayish brown (10YR 5/2) dry; weak fine granular structure; very friable; slightly effervescent; slightly alkaline; abrupt smooth boundary. (6 to 9 inches thick)
C1--7 to 24 inches; stratified dark grayish brown (10YR 4/2) and grayish brown (10YR 5/2) silt loam; massive with weak thin alluvial stratification; very friable; few fine distinct yellowish brown (10YR 5/4) and few fine prominent yellowish brown (10YR 5/6) redoximorphic concentrations; strongly effervescent; moderately alkaline; abrupt smooth boundary. (12 to 21 inches thick)
2C2--24 to 60 inches; very dark grayish brown (2.5Y 3/2) and dark grayish brown (2.5Y 4/2) silty clay; massive with weak thin alluvial stratification; very firm; dark gray (N 4/0) coatings on faces of some peds; few fine distinct dark yellowish brown (10YR 4/4) redoximorphic concentrations; strongly effervescent; moderately alkaline.
TYPE LOCATION: Pottawattamie County, Iowa; about 1 mile south and 3.5 miles west of Loveland; about 1,340 feet east and 700 feet north of the southwest corner of sec. 12, T. 77 N., R. 45 W.; USGS Loveland quadrangle; lat. 41 degrees 28 minutes 43 seconds N. and long. 95 degrees 58 minutes 13 seconds W., NAD 27
RANGE IN CHARACTERISTICS:
Depth to carbonates--less than 10 inches
Depth to clayey alluvium--18 to 30 inches
Content of clay in the upper third to upper half of the particle-size control section (weighted average)--10 to 18 percent
Content of clay in the lower half to lower two thirds of the particle-size control section (weighted average)--40 to 60 percent
Content of sand in the particle-size control section (weighted average)--less than 15 percent fine sand and sand coarser than fine sand
Ap or A horizon:
Hue--10YR or 2.5Y
Value--3
Chroma--1 to 3
Texture--silt loam, loam, very fine sandy loam, or silty clay loam
Clay content--10 to 30 percent
Sand content--15 to 70 percent, mostly very fine sand
Reaction--slightly alkaline or moderately alkaline
Calcium carbonate equivalent--0 to 15 percent
C or Cg horizon:
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--2 to 4
Texture--silt loam, loam, very fine sandy loam, or is stratified with these textures
Clay content--10 to 18 percent
Sand content--15 to 70 percent, mostly very fine sand, less than 15 percent fine sand and sand coarser than fine sand
Calcium carbonate equivalent--5 to 20 percent
Reaction--slightly alkaline or moderately alkaline
Some pedons have thin strata of very fine sand or silty clay
2C or 2Cg horizon:
Hue--10YR, 2.5Y, 5Y, or is neutral
Value--3 to 5
Chroma--0 to 3
Texture--silty clay or clay
Clay content--50 to 75 percent
Sand content--1 to 20 percent, mostly very fine sand
Calcium carbonate equivalent--1 to 15 percent
Reaction--slightly alkaline or moderately alkaline
Some pedons have strata of darker colored silt loam, 2 to 4 inches thick
3Bgb horizon (if it occurs):
Hue--2.5Y, 5Y, or is neutral
Value--4 or 5
Chroma--0 to 2
Texture--silty clay or clay
Clay content--50 to 75 percent
Sand content--1 to 15 percent
Calcium carbonate equivalent--1 to 20 percent
Reaction--slightly alkaline or moderately alkaline
3Cg horizon (if it occurs):
Hue--2.5Y, 5Y, or is neutral
Value--4 or 5
Chroma--0 to 2
Texture--silty clay or clay
Clay content--50 to 75 percent
Sand content--1 to 15 percent
Calcium carbonate equivalent--0 to 20 percent
Reaction--slightly alkaline or moderately alkaline
COMPETING SERIES: This is the
Moville series.
Moville--have buried horizons with a matrix color value of 3 or less and chroma of 1 or less within a depth of 18 to 32 inches
GEOGRAPHIC SETTING:
Parent material--18 to 30 inches of silty alluvium and the underlying clayey alluvium
Landform--flood plains
Slopes--0 to 2 percent
Elevation--950 to 1,150 feet above sea level
Mean annual air temperature--47 to 56 degrees F.
Mean annual precipitation--20 to 36 inches
Frost-free period--150 to 175 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Albaton,
Grable,
Haynie,
Percival, and
Sarpy soils.
Albaton--are at the slightly lower elevations and have a clay content of 60 to 70 percent throughout the particle-size control section
Grable--are at the slightly higher elevations and have a sand content of 65 to 95 percent in the lower two thirds of the series control section
Haynie--are at the slightly higher elevations and have a clay content of 15 to 18 percent throughout the particle-size control section
Percival--are in similar landscape positions to those of the Modale soils and have a clay content of 2 to 12 percent in the lower two thirds of the particle-size control section
Sarpy--are at the higher elevations and have a clay content of 2 to 5 percent throughout the particle-size control section
DRAINAGE AND PERMEABILITY:
Drainage class--somewhat poorly drained--a saturated zone occurs within a depth of 1 to 3 feet during April to June in most years and is considered apparent
Permeability--moderate in the silty alluvium and slow or very slow in the underlying clayey alluvium
Surface runoff potential--low
Flooding--rarely flooded or occasionally flooded for very brief or brief periods during the months of February to November
USE AND VEGETATION:
Most areas are cultivated. The principal crops are corn and soybeans, oats and hay. A few areas are irrigated. The native vegetation is big bluestem, little bluestem, indiangrass, switchgrass, and other grasses of the tall grass prairie.
DISTRIBUTION AND EXTENT:
LRR M, MLRA107; western Iowa, Nebraska, South Dakota, and Missouri. This series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Monona County, Iowa, 1957.
REMARKS:
Particle-size control section--the zone from a depth of 10 to 40 inches (C1 and 2C2 horizons);
Series control section--the zone from the surface to a depth of 60 inches (Ap, C1, and 2C2 horizons).
Diagnostic horizons and features recognized in this pedon:
ochric epipedon--the zone from surface to a depth of 7 inches (Ap horizon);
udic moisture regime.
Cation-exchange class is inferred from lab data for similar soils in the surrounding area.
Taxonomy version--second edition, 1999.
This series is not considered to meet the saturation requirements of the Aquents suborder.
ADDITIONAL DATA:
Laboratory data--Iowa State University Experiment Station, Ames, IA, file numbers 17328 to 17329 and 17352.