LOCATION TERRIL IA+IL MN WIEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Cumulic Hapludolls
TYPICAL PEDON: Terril loam, on a foot slope of about 4 percent, in a cultivated field. (Colors are for moist soil unless otherwise indicated.)
Ap--0 to 23 centimeters (0 to 9 inches); black (10YR 2/1) loam, very dark gray (10YR 3/1) dry; weak fine subangular blocky structure parting to moderate fine and medium granular; friable; neutral; abrupt smooth boundary.
A1--23 to 38 centimeters (9 to 15 inches); black (10YR 2/1) loam, very dark gray (10YR 3/1) dry; a few peds of very dark brown (10YR 2/2); weak very fine and fine subangular blocky structure parting to moderate fine and medium granular; friable; neutral; gradual smooth boundary.
A2--38 to 58 centimeters (15 to 23 inches); black (10YR 2/1) loam, very dark gray (10YR 3/1) dry; weak medium prismatic structure parting to fine and medium subangular blocky; friable; neutral; gradual smooth boundary.
A3--58 to 81 centimeters (23 to 32 inches); black (10YR 2/1) and very dark gray (10YR 3/1) loam, very dark gray (10YR 3/1) dry; weak medium prismatic structure parting to weak fine and medium subangular blocky; friable; neutral; gradual smooth boundary.
A4--81 to 91 centimeters (32 to 36 inches); very dark brown (10YR 2/2) and very dark grayish brown (10YR 3/2) loam, dark grayish brown (10YR 4/2) and very dark grayish brown (10YR 3/2) dry; weak medium prismatic structure parting to moderate fine and medium subangular blocky; friable; neutral; clear smooth boundary. [Combined thickness of the A horizon is 61 to 152 centimeters (24 to 60 inches).]
Bw1--91 to 109 centimeters (36 to 43 inches); brown (10YR 4/3) loam; weak medium prismatic structure parting to weak fine and medium subangular blocky; friable; few fine tubular pores; common distinct very dark grayish brown (10YR 3/2) coats on faces of peds; neutral; gradual smooth boundary.
Bw2--109 to 127 centimeters (43 to 50 inches); dark yellowish brown (10YR 4/4) loam; weak medium prismatic structure parting to weak medium subangular blocky; friable; few fine tubular pores; common dark yellowish brown (10YR 3/4) and few very dark grayish brown (10YR 3/2) coats on faces of peds; neutral; gradual smooth boundary. [Combined thickness of the Bw horizon is 10 to 51 centimeters (4 to 20 inches)].
BC--127 to 152 centimeters (50 to 60 inches); dark yellowish brown (10YR 4/4) loam; weak medium prismatic structure; friable; common fine tubular pores; neutral.
TYPE LOCATION: Major Land Resource Area (MLRA) 103-Central Iowa and Minnesota Till Prairies; Emmet County, Iowa subset; about 183 meters (600 feet) east and 18 meters (60 feet) south of the northwest corner of section 25, T. 99 N., R. 34 W.; USGS Wallingford quadrangle, lat. 43 degrees 22 minutes 13 seconds N. and long. 94 degrees 48 minutes 50 seconds W., NAD 83.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon--61 to 152 centimeters (24 to 60 inches)
Depth to carbonates--more than 102 centimeters (40 inches)
Clay content of the particle-size control section (weighted average)--18 to 27 percent
Sand content of the particle-size control section (weighted average)--25 to 60 percent
A horizon:
Hue--10YR
Value--2 or 3
Chroma--1 or 2
Texture--loam, silt loam high in sand, or clay loam
Clay content--18 to 30 percent
Sand content--15 to 40 percent
Rock fragment content--0 to 5 percent
Reaction--slightly acid or neutral
Some pedons have an AB or BA horizon
Bw and BC horizons:
Hue--10YR or 2.5Y
Value--3 or 4
Chroma--3 or 4
Texture--loam, clay loam, or sandy loam
Clay content--18 to 30 percent
Sand content--25 to 60 percent
Rock fragment content--0 to 5 percent
Reaction--slightly acid or neutral
Some pedons have a Bk horizon
C horizon (when present):
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--3 or 4
Texture--loam, clay loam, or sandy clay loam
Clay content--15 to 30 percent
Sand content--25 to 60 percent
Rock fragment content--0 to 5 percent
Reaction--slightly acid to moderately alkaline
COMPETING SERIES: These are the
Dameron,
Deloit,
Du Page,
Olmitz,
Racket,
Ross,
Spillco,
Spillville, and
Turlin series.
Dameron--have more than 15 percent rock fragments within a depth of 102 centimeters (40 inches)
Deloit--do not have a frequently saturated zone within a depth of 1.8 meters (6 feet) in normal years
Du Page--have carbonates within a depth of 25 centimeters (10 inches)
Olmitz--have a clay content of 28 to 34 percent in the particle-size control section
Racket--have more than 15 percent rock fragments in the lower third of the series control section
Ross--have carbonates between depths of 61 to 114 centimeters (24 to 45 inches)
Spillco--have carbonates between depths of 30 to 91 centimeters (12 to 36 inches)
Spillville--have a frequently saturated zone within depths of 0.3 to 0.6 meters (1 to 2 feet) in normal years and have a clay content of 5 to 24 percent in the lower third of the series control section
Turlin--have a frequently saturated zone within depths of 0.3 to 0.9 meters (1 to 3 feet) in normal years and have a clay content of 8 to 18 percent in the lower third of the series control section
GEOGRAPHIC SETTING:
Parent material--colluvium
Landform--base slopes, foot slopes, drainageways, swales and toe slopes on alluvial fans, and treads and risers on stream terraces
Slopes--0 to 25 percent
Elevation--305 to 442 meters (1,000 to 1,450 feet) above sea level
Mean annual air temperature--7 to 11 degrees C (45 to 52 degrees F)
Mean annual precipitation--58 to 86 centimeters (23 to 34 inches)
Frost-free period--145 to 180 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Clarion,
Colo,
Lester, and
Storden soils.
Clarion--are at higher elevations on side slopes and have mollic epipedons 25 to 56 centimeters (10 to 22 inches) thick
Colo--are at lower elevations on toe slopes and in floodplains and have a frequently saturated zone within 0.3 meters in normal years
Lester--are at higher elevations on side slopes and have dark-colored surface layers 15 to 25 centimeters (6 to 10 inches) thick
Storden--are at higher elevations on side slopes and have carbonates throughout the series control section
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--moderately well drained--a frequently saturated zone occurs within depths of 1 to 1.8 meters (3.25 to 6 feet) during March to June in normal years
Saturated hydraulic conductivity--moderately high or high
Surface runoff potential--negligible to high, depending on slope
USE AND VEGETATION:
Many areas next to steep slopes or bottom land are in permanent pasture. Other areas are cultivated. The principal crops are corn, legume meadow, oats, 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-- Western lake section, Eastern lake section, Wisconsin driftless section, Dissected till plains, and Till plains
MLRAs--Till Plains (102B), Central Iowa and Minnesota Till Prairies (103), Eastern Iowa and Minnesota Till Prairies (104), Northern Mississippi Valley Loess Hills (105), Iowa and Missouri Deep Loess Hills (107), Illinois and Iowa Deep Loess and Drift (108), and Southern Illinois and Indiana Thin Loess and Till Plain (114)
LRR M; North-central Iowa, Illinois, south-central Minnesota, and Wisconsin
Extent--large
MLRA OFFICE RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Dickinson County, Iowa, 1944
REMARKS:
Particle-size control section--the zone from a depth of 25 to 100 centimeters (10 to 39 inches) (A1, A2, A3, A4, and Bw1 horizons);
series control section--the zone from the surface to a depth of 150 centimeters (59 inches) (Ap, A1, A2, A3, A4, Bw1, Bw2, and BC horizons).
Diagnostic horizons and features recognized in this pedon:
mollic epipedon--the zone from the surface to a depth of 91 centimeters (36 inches) (Ap, A1, A2, A3, and A4 horizons);
cambic horizon--the zone from a depth of 91 to 152 centimeters (36 to 60 inches) (Bw1, Bw2, and BC horizons);
udic moisture regime.
Type location moved from Humboldt County where lab data (ISU) showed it to be coarse-loamy particle-size family. Moved to Emmet County to better typify the series concept.
Cation-exchange class is inferred from lab data for similar soils in the surrounding area.
Taxonomy version--Keys to Soil Taxonomy, ninth edition, 2003.
ADDITIONAL DATA:
Laboratory data--Iowa State University, Ames, Iowa