LOCATION FOSTORIA IA+MNEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Aquic Hapludolls
TYPICAL PEDON: Fostoria loam, on a slope of about 1 percent, in a cultivated field. (Colors are for moist conditions unless otherwise stated.)
Ap--0 to 18 centimeters; black (N 2/0) loam, very dark gray (10YR 3/1) dry; moderate fine and medium granular structure; friable; common very fine and fine roots; neutral; abrupt smooth boundary.
A1--18 to 38 centimeters; black (N 2/0) loam, very dark gray (10YR 3/1) dry; weak fine granular structure; friable; common very fine and fine roots; neutral; gradual smooth boundary.
A2--38 to 48 centimeters; black (10YR 2/1) loam, dark gray (10YR 4/1) dry; some mixing of dark grayish brown (2.5Y 4/2); weak very fine subangular blocky and weak fine granular structure; friable; common very fine and fine roots; neutral; gradual smooth boundary. (Combined thickness of the A horizon is 30 to 49 centimeters.)
BA--48 to 61 centimeters; dark grayish brown (2.5Y 4/2) loam; very weak fine subangular blocky structure; friable; common very fine roots; many distinct very dark grayish brown (10YR 3/2) organic coats on faces of peds; neutral; gradual smooth boundary. (0 to 20 centimeters thick)
Bg--61 to 74 centimeters; dark grayish brown (2.5Y 4/2) loam; weak fine subangular blocky structure; friable; common very fine roots; common fine distinct olive brown (2.5Y 4/4) redoximorphic concentrations; neutral; gradual smooth boundary. (10 to 50 centimeters thick)
Bk--74 to 86 centimeters; olive brown (2.5Y 4/4) loam; weak fine and medium subangular blocky structure; friable; common very fine roots; common fine and medium very pale brown (10YR 8/2) calcium carbonate concretions; common fine distinct light olive brown (2.5Y 5/6) redoximorphic concentrations; strongly effervescent; moderately alkaline; abrupt wavy boundary. (0 to 20 centimeters thick)
2C--86 to 107 centimeters; light olive brown (2.5Y 5/4) silt loam; massive; friable; common fine and medium very pale brown (10YR 8/2) rounded calcium carbonate concretions; common fine distinct yellowish brown (10YR 5/6) and common fine prominent yellowish brown (10YR 5/8) redoximorphic concentrations; common medium distinct gray (10YR 5/1) redoximorphic depletions; strongly effervescent; moderately alkaline; gradual smooth boundary.
2Cg1--107 to 152 centimeters; gray (10YR 5/1) silt loam; massive; friable; common fine and medium very pale brown (10YR 8/2) calcium carbonate concretions; many fine and medium prominent yellowish brown (10YR 5/6) and yellowish brown (10YR 5/8) redoximorphic concentrations; strongly effervescent; moderately alkaline; gradual smooth boundary.
2Cg2--152 to 173 centimeters; grayish brown (2.5Y 5/2) silt loam; massive; friable; many fine and medium prominent light olive brown (2.5Y 5/6) redoximorphic concentrations; strongly effervescent; moderately alkaline; abrupt wavy boundary.
3C--173 to 200 centimeters; yellowish brown (10YR 5/6) loam; massive; firm; common fine prominent grayish brown (2.5Y 5/2) redoximorphic depletions; about 3 percent gravel; strongly effervescent; moderately alkaline.
TYPE LOCATION: Major Land Resource Are (MLRA) 107A-Iowa and Minnesota Loess Hills, Clay County, Iowa subset; about 1 mile west and 1 mile north of Everly; located about 125 feet north and 150 feet west of the southeast corner of section 29, T. 97 N., R. 38 W.; USGS Everly, Iowa topographic quadrangle; lat. 43 degrees 11 minutes 03 seconds N. and long. 95 degrees 20 minutes 55 seconds W., NAD 83.
RANGE IN CHARACTERISTICS:
Thickness of the mollic epipedon--30 to 49 centimeters
Depth to carbonates--60 to 120 centimeters
Clay content in the particle-size control section (weighted average)--18 to 25 percent
Sand content in the particle-size control section (weighted average)--30 to 50 percent
Rock fragment content in the series control section--0 percent
Ap and A horizon:
Hue--10YR or neutral
Value--2 or 3
Chroma--0 or 1
Texture--loam, silt loam, or clay loam
Clay content--18 to 28 percent
Sand content--25 to 45 percent
Reaction--slightly acid or neutral
AB or BA horizon:
Hue--10YR or 2.5Y
Value--3 or 4
Chroma--2
Texture--loam, silt loam, or clay loam
Clay content--18 to 28 percent
Sand content--25 to 45 percent
Reaction--slightly acid or neutral
Bg, Bw, or Bk horizon:
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--1 to 4
Texture--loam or silt loam, and includes fine sandy loam or sandy loam in the lower part
Clay content--15 to 25 percent
Sand content--8 to 55 percent
Reaction--slightly acid to moderately alkaline
Some pedons have a 2Bw horizon
2C or 2Cg horizon:
Hue--10YR or 2.5Y
Value--4 to 6
Chroma--1 to 6
Texture--silt loam, loam, or sandy loam
Clay content--15 to 25 percent
Sand content--6 to 55 percent
Reaction--slightly alkaline or moderately alkaline
3C horizon:
Hue--10YR or 2.5Y
Value--5 or 6
Chroma--1 to 6
Texture--loam
Clay content--18 to 27 percent
Sand content--20 to 45 percent
Reaction--slightly alkaline or moderately alkaline
Lacustrine substratum, below a depth of 150 centimeters (when present):
Hue--2.5Y or 5Y
Value--4 or 5
Chroma--1 to 4
Texture--silt loam, silty clay loam, silty clay or clay
Clay content--20 to 35 percent
Sand content--2 to 20 percent
Reaction--slightly alkaline or moderately alkaline
COMPETING SERIES: These are the
Arkton,
Crippin,
Kensett,
Merton,
Nicollet,
Normania,
Ottosen,
Readlyn,
Snider,
Stone,
Walnut Grove, and
Wilmonton series.
Arkton--have a clay content that averages 27 to 35 percent in the particle-size control section
Crippin--slightly alkaline or moderately alkaline in the upper half of the series control section
Kensett--have a lithic contact with limestone within a depth of 100 centimeters
Merton--have a rock fragment contact of 2 to 15 percent in the lower half of the series control section
Nicollet--have a rock fragment contact of 1 to 8 percent throughout the series control section
Normania--have a rock fragment contact of 2 to 8 percent throughout the series control section
Ottosen--have a clay content that averages 30 to 35 percent in the particle-size control section
Readlyn--have a rock fragment contact of 2 to 12 percent in the lower half of the series control section
Snider--do not have carbonates within a depth of 150 centimeters
Stone--have a lithic contact with limestone within a depth of 150 centimeters
Walnut Grove--have a rock fragment contact of 1 to 8 percent throughout the series control section
Wilmonton--have a rock fragment contact of 2 to 8 percent in the lower half of the series control section
GEOGRAPHIC SETTING:
Parent material--loamy glacial sediments of mixed lithology
Landform--nearly level to slightly concave positions on till plains
Slope--0 to 3 percent
Elevation--300 to 520 meters above sea level
Mean annual air temperature--6 to 10 degrees C
Mean annual precipitation--585 to 890 millimeters
Frost-free period--155 to 200 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Afton,
Gillett Grove,
Ocheyedan, and
Roine soils.
Afton--are on lower landscape positions in nearly level upland drainageways and have a mollic epipedon 60 to 90 centimeters thick
Gillett Grove--are on lower landscape positions in nearly level upland flats and swales and are frequently saturated from the surface to a depth of 0.3 meter during the wettest periods of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Ocheyedan--are on slightly higher landscape positions and have a frequently saturated zone between depths of 1.0 and 1.8 meters during the wettest periods of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Roine--are on slightly higher landscape positions and have a clay content that averages 8 to 18 percent in the particle-size control section
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--somewhat poorly drained--in a natural condition, a frequently saturated zone occurs between depths of 0.3 and 1.0 meters during the wettest periods of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Saturated hydraulic conductivity--1.0 to 10.0 micrometers per second
USE AND VEGETATION:
Most areas are cultivated. The principal crops are corn and soybeans. The native vegetation is big bluestem, little bluestem, switchgrass, and other grasses of the tall grass prairie.
DISTRIBUTION AND EXTENT:
Physiographic Division--Interior Plains
Physiographic Province--Central Lowland
Physiographic sections--Dissected till plains and Western lake section
MLRAs--Central Iowa and Minnesota Till Prairies (103) and Iowa and Minnesota Loess Hills (107A)
LRR M--northwestern Iowa and southern Minnesota
Extent--moderate
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana; MLRA SSO 10-6 (Atlantic, Iowa)
SERIES ESTABLISHED: Clay County, Iowa, 1975.
REMARKS:
Particle-size control section--the zone from a depth of 25 to 100 centimeters;
series control section--the zone from the surface to a depth of 150 centimeters.
Diagnostic horizons and features recognized in this pedon include:
mollic epipedon--the zone from the surface of the soil to a depth of 48 centimeters (Ap, A1 and A2 horizons);
cambic horizon--the zone from a depth of 48 to 86 centimeters (BA, Bg and Bk horizons);
udic moisture regime.
A lacustrine substratum phase was correlated in Clay County, Iowa and is of very minor extent. It is on a lake plain.
Cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.
Taxonomy version--Keys to Soil Taxonomy, tenth edition, 2006.