LOCATION MASSBACH IL+IA MNEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Mollic Hapludalfs
TYPICAL PEDON: Massbach silt loam. (Colors are for moist soil unless otherwise stated.)
A--0 to 18 centimeters; very dark gray (10YR 3/1) silt loam, very dark grayish brown (10YR 3/2) when crushed, grayish brown (10YR 5/2) dry; moderate fine and medium granular structure; friable; abundant roots; neutral; clear smooth boundary. (12 to 26 centimeters thick)
E--18 to 28 centimeters; dark grayish brown (10YR 4/2) and brown (10YR 4/3) silt loam; moderate fine and medium granular structure; friable; abundant roots; some light gray (10YR 7/2) dry silt coats; slightly acid; clear smooth boundary. (4 to 16 centimeters thick)
BE--28 to 36 centimeters; brown (10YR 4/3) and dark yellowish brown (10YR 4/4) silty clay loam; moderate fine subangular blocky structure; firm; abundant roots; some light gray (10YR 7/2) dry silt coats; moderately acid; clear smooth boundary. (7 to 16 centimeters thick)
Bt1--36 to 61 centimeters; brown (10YR 4/3) silty clay loam; moderate fine and medium subangular blocky structure; firm; plentiful roots; few light gray (10YR 7/1) dry silt coats on faces of peds; continuous dark brown (10YR 3/3) clay films on faces of peds; moderately acid; clear smooth boundary.
Bt2--61 to 84 centimeters; dark yellowish brown (10YR 4/4) silty clay loam; moderate fine and medium subangular blocky structure; firm; plentiful roots; common worm casts of very dark gray (10YR 3/1); few light gray (10YR 7/1) dry silt coats on faces of peds; thin discontinuous brown (10YR 4/3) clay films on faces of peds; moderately acid; clear smooth boundary.
Bt3--84 to 99 centimeters; dark yellowish brown (10YR 4/4) silty clay loam; moderate fine and medium subangular blocky structure; firm; few fine roots; few light gray (10YR 7/1) dry silt coats on faces of peds; thin discontinuous brown (10YR 4/3) clay films on faces of peds; few black (10YR 2/1) iron-manganese stains and concretions; moderately acid; abrupt smooth boundary. (Combined thickness of the Bt horizon is 60 to 85 centimeters.)
2Bt4--99 to 117 centimeters; pale olive (5Y 6/4) silty clay; moderate medium subangular blocky structure; very firm; few fine roots; thin discontinuous dark brown to brown (10YR 4/3) clay films on ped faces; common medium distinct strong brown (7.5YR 5/6) masses of iron and manganese oxide accumulation; slightly acid; abrupt smooth boundary. Horizon is mostly weathered shale. (12 to 26 centimeters thick)
2Cr--117 to 150 centimeters; pale olive (5Y 6/4), yellowish brown (10YR 5/8) and brownish yellow (10YR 6/8) silty clay; massive; very firm; calcareous shale.
TYPE LOCATION: Major Land Resource Area (MLRA) 105-Northern Mississippi Valley Loess Hills, Stephenson County, Illinois subset; about 4 miles northeast of Pearl City; located about 530 feet south and 760 feet west of the northeast corner of section 35, T. 27 N., R. 5 E.; USGS Kent topographic quadrangle; lat. 42 degrees 17 minutes 48 seconds N. and long. 89 degrees 53 minutes 05 seconds W., NAD 83.
RANGE IN CHARACTERISTICS:
Thickness of loess--75 to 125 centimeters
Depth to paralithic contact--100 to 150 centimeters
Clay content in the particle-size control section (weighted average)--25 to 35 percent
Sand content in the particle-size control section (weighted average)--less than 10 percent
Rock fragment content--0 percent
A or Ap horizon:
Hue--10YR
Value--2 or 3, moist and 4 or 5, dry
Chroma--1 or 2
Texture--silt loam or silty clay loam
Clay content--22 to 30 percent
Sand content-- less than 10 percent
Reaction--moderately acid to neutral
E horizon:
Hue--10YR
Value--4 or 5
Chroma--2 or 3
Texture--silt loam
Clay content--15 to 25 percent
Sand content--less than 10 percent
Reaction--moderately acid to neutral
Bt horizon:
Hue--7.5YR or 10YR
Value--4 or 5
Chroma--3 or 4
Texture--silty clay loam or silt loam
Clay content--25 to 35 percent
Sand content--less than 10 percent
Reaction--moderately acid to slightly alkaline
Redoximorphic depletions with chroma of 2 or less are below a depth of 75 centimeters
2Bt horizon:
Hue--10YR, 2.5Y, 5Y, 5G, 5GY, or 5BG
Value--4 to 6
Chroma--2 to 4
Texture--silty clay loam, silty clay, or clay
Clay content--35 to 50 percent
Sand content--less than 10 percent
Reaction--slightly acid to slightly alkaline
Hues of 5Y, 5GY, 5G, and 5BG are inherited from the shale bedrock
The 2Bt commonly has masses of iron and manganese accumulation with high chroma
Some pedons have 2C horizons in residuum from shale
The 2Cr horizon is calcareous silty clay or clay shale
COMPETING SERIES: These are the
Batavia,
Bowes,
Churchtown,
Deroin,
Downs,
Ella,
Festina,
Frankville,
Gladek,
Greenbush,
Harvard,
Hersey,
Knox,
Luana,
Mannon,
Mellott,
Mt. Carroll,
Myrtle,
Nasset,
Newhouse,
Oak Center,
Watkins,
Waubeek, and
Yutan series.
Batavia--have more than 10 percent sand in the lower third of the series control section
Bowes--have more than 30 percent sand and have a rock fragment content of more than 15 percent in the lower third of the series control section
Churchtown--have 10 to 55 percent sand in the upper half of the series control section
Deroin--have a matrix hue of 5YR or 7.5YR in the lower two thirds of the series control section
Downs--do not have a paralithic contact within a depth of 150 centimeters
Ella--have an average of 15 to 60 percent fine sand or sand coarser than fine sand in the lower third of the series control section
Festina--do not have a paralithic contact within a depth of 150 centimeters
Frankville--have a lithic contact with limestone within a depth of 100 centimeters
Gladek--do not have a paralithic contact within a depth of 150 centimeters
Greenbush--have a frequently saturated zone at a depth of 1.2 meters centimeters during the wettest periods of normal years
Harvard--have more than 15 percent sand in the lower one third of the series control section
Hersey--have a rock fragment content of 2 to 15 percent and average more than 15 percent fine sand and sand coarser than fine sand in the lower third of the series control section
Knox--are in areas that have mean annual air temperature range of 12 to 14 degrees C and do not have a paralithic contact within a depth of 150 centimeters
Luana--have a rock fragment content of 10 to 35 percent in the lower third of the series control section
Mannon--have a clay content that averages 18 to 27 percent in the particle-size control section and have a frequently saturated zone at a depth of 1.2 meters during the wettest periods of normal years
Mellott--have carbonates within a depth of 150 centimeters and have a sand content of 35 to 65 percent in the lower third of the series control section
Mt. Carroll--do not have a paralithic contact within a depth of 150 centimeters
Myrtle--have a matrix hue of 2.5YR, 5YR or 7.5YR in the lower third of the series control section
Nassett--have a lithic contact with limestone within a depth of 150 centimeters
Newhouse--have a clay content that averages 18 to 27 percent in the particle-size control section and have 5 to 35 percent chert and sandstone fragments in the lower third of the series control section
Oak Center--have a sand content of more than 35 percent within a depth of 150 centimeters
Watkins--have a clay content that averages 30 to 35 percent in the particle-size control section and have a clay content of 27 to 32 percent in the lower third of the series control section
Waubeek--have a sand content of 35 to 65 percent in the lower third of the series control section
Yutan--have a clay content of 35 to 40 percent in the ochric epipedon
GEOGRAPHIC SETTING:
Parent material--75 to 125 centimeters of loess and residuum from calcareous clayey Maquoketa or Decorah shale of Ordovician Age
Landform--gently undulating to rolling shale ridges and side slopes on uplands
Slope--0 to 35 percent
Elevation--200 to 400 meters above sea level
Mean annual air temperature--6 to 12 degrees C
Mean annual precipitation--735 to 990 millimeters
Frost-free period--145 to 210 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Eleroy,
Keltner, and
Ridott soils.
Eleroy--are on landscape positions similar to those of the Massbach soils and have a lighter-colored ochric epipedon
Keltner--are on landscape positions similar to those of the Massbach soils and have a mollic epipedon 25 to 60 centimeters thick
Ridott--are in lower landscape positions and have redoximorphic features within a depth of 0.3 meter of the surface.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained and moderately well drained--a frequently saturated zone occurs at a depth of 1.2 meters during March to June in normal years and is considered perched
Saturated hydraulic conductivity--1.00 to 10.00 micrometers per second in the loess and 0.10 to 1.00 micrometers per second in the residuum
Surface runoff potential--negligible to high
USE AND VEGETATION:
Most areas are cultivated. The principal crops are corn, soybeans, small grain and grass and legume hay. The native vegetation is mixed tall grass prairie and deciduous trees.
DISTRIBUTION AND EXTENT:
Physiographic Division--Interior Plains
Physiographic Province--Central Lowland
Physiographic sections--Eastern lake section, Wisconsin driftless section, Dissected till plains, Till plains
MLRAs--Southern Wisconsin and Northern Illinois Drift Plain (95B),
Eastern Iowa and Minnesota Till Prairies (104),
Northern Mississippi Valley Loess Hills (105), and
Illinois and Iowa Deep Loess and Drift (108)
LRR M and LRR K; northwestern Illinois and southeastern Minnesota
Extent--moderate
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Stephenson County, Illinois, 1969.
REMARKS:
Particle-size control section--the zone from a depth of 36 to 86 centimeters (Bt1, Bt2, and Bt3 horizons);
series control section--the zone from the surface to a depth of 150 centimeters (A, E, BE, Bt1, Bt2, Bt3, 2Bt4, and 2Cr horizons).
Diagnostic horizons and features recognized in this pedon include:
ochric epipedon--the zone from the surface to a depth of 36 centimeters (A, E and BE horizons);
albic horizon--the zone from a depth of 18 to 28 centimeters (E horizon);
argillic horizon--the zone from a depth of 36 to 117 centimeters (Bt1, Bt2, Bt3, and 2Bt4 horizons);
paralithic contact--the zone beginning at a depth of 117 centimeters (2Cr horizon);
udic moisture regime.
Cation-exchange class is inferred from lab data from similar soils in the surrounding area. Taxonomy version: Second Edition, 1999.
Taxonomy version--Keys to Soil Taxonomy, tenth edition, 2006.