LOCATION MERTON MNEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Aquic Hapludolls
TYPICAL PEDON: Merton silt loam, on a linear slope of 2 percent, in a cultivated field, at an elevation of about 378 meters above sea level. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 20 centimeters; black (10YR 2/1) silt loam; very dark gray (10YR 3/1) dry; weak medium granular structure; friable; slightly acid; abrupt smooth boundary.
A--20 to 41 centimeters; very dark gray (10YR 3/1) silt loam; dark gray (10YR 4/1) dry; weak fine subangular blocky structure; friable; slightly acid; clear wavy boundary. (Combined thickness of the A horizon is 25 to 46 centimeters thick.)
Bw1--41 to 58 centimeters; dark grayish brown (2.5Y 4/2) silt loam; weak fine subangular blocky structure; friable; few tongues of very dark grayish brown (10YR 3/2); common tubular pores; slightly acid; clear wavy boundary. (8 to 25 centimeters thick)
2Bw2--58 to 71 centimeters; grayish brown (2.5Y 5/2) loam high in content of silt; weak medium subangular blocky structure; friable; common tubular pores; about 5 percent rock fragments; slightly acid; clear wavy boundary.
2Bw3--71 to 81 centimeters; grayish brown (2.5Y 5/2) loam; weak medium subangular blocky structure; friable; dark grayish brown (2.5Y 4/2) coats on faces of peds; many fine faint light olive brown (2.5Y 5/4) masses of iron accumulation; about 5 percent rock fragments; slightly acid; clear wavy boundary.
2Bw4--81 to 91 centimeters; olive brown (2.5Y 4/4) loam; moderate medium prismatic structure; friable; about 5 percent rock fragments; slightly acid; clear wavy boundary. (Combined thickness of the 2Bw horizon is 22 to 72 centimeters.)
2BC--91 to 122 centimeters; light olive brown (2.5Y 5/4) loam; moderate medium prismatic structure; friable; about 5 percent rock fragments; slightly acid; clear wavy boundary. (0 to 50 centimeters thick)
2C--122 to 152 centimeters; light olive brown (2.5Y 5/4) loam; massive; friable; about 5 percent coarse fragments; many fine faint light olive brown (2.5Y 5/6) masses of iron accumulation; strongly effervescent; slightly alkaline.
TYPE LOCATION: Major Land Resource Area (MLRA) 103-Central Iowa and Minnesota Till Prairies; Steele County, Minnesota subset; about 9 miles east and 1 mile north of Medford; located about 1,100 feet north and 100 feet east of the southwest corner of section 2, T. 108 N., R. 19 W.; USGS Moland topographic quadrangle; lat. 44 degrees 11 minutes 07 seconds N. and long. 93 degrees 05 minutes 09 seconds W., NAD 83.
RANGE IN CHARACTERISTICS:
Mollic epipedon thickness--30 to 46 centimeters
Depth to glacial till--35 to 60 centimeters
Depth to carbonates--90 to 165 centimeters
Clay content in the particle-size control section (weighted average)--20 to 28 percent
Sand content in the particle-size control section (weighted average)--15 to 35 percent, fine sand and sand coarser than fine sand
Special feature--some pedons have a thin stone line, 2 to 13 centimeters thick with up to 10 percent rock fragments at the base of the silty or loamy sediments
Ap and A horizon:
Hue--10YR
Value--2 or 3
Chroma--1 or 2
Texture--loam, silt loam, or silty clay loam
Clay content--18 to 32 percent
Sand content--10 to 30 percent
Rock fragment content--0 to 1 percent, mixed lithology
Reaction--moderately acid to neutral
Bw horizon:
Hue--10YR. or 2.5Y
Value--4 or 5
Chroma--2 or 3
Texture--loam, silt loam, or silty clay loam
Clay content--18 to 30 percent
Sand content--10 to 30 percent
Rock fragment content--0 to 1 percent, mixed lithology
Reaction--moderately acid to neutral
2Bw or 2BC (when present) horizon:
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--2 to 4
Texture--loam or clay loam
Clay content--18 to 27 percent
Sand content--30 to 45 percent
Rock fragment content--2 to 15 percent, mixed lithology
Reaction--moderately acid to slightly alkaline
2C horizon:
Hue--2.5Y
Value--4 or 5
Chroma--2 to 5
Texture--loam or sandy loam
Clay content--18 to 27 percent
Sand content--45 to 70 percent
Rock fragment content--2 to 15 percent, mixed lithology
Calcium carbonate equivalent--5 to 15 percent
Reaction--moderately acid to slightly alkaline
Moist bulk density--1.5 to 1.7 gm/cc
COMPETING SERIES: These are the
Arkton,
Crippin,
Floyd,
Fostoria,
Kensett,
Nicollet,
Normania,
Ottosen,
Readlyn,
Snider,
Stone, and
Wilmonton series.
Arkton--have carbonates within a depth of 25 centimeters
Crippin--have carbonates within a depth of 25 centimeters
Floyd--have a moist bulk density of more than 1.75 gm/cc in the lower third of the series control section
Fostoria--do not have rock fragments in the series control section
Kensett--have a lithic contact of limestone within a depth of 102 centimeters
Nicollett--have a rock fragment content of more than 1 percent in the upper third of the series control section
Normania--have a rock fragment content of more than 1 percent in the upper third of the series control section
Ottosen--have an average clay content of 30 to 35 percent in the particle-size control section
Readlyn--have a moist bulk density of more than 1.75 gm/cc in the lower third of the series control section
Snider--do not have rock fragments in the series control section
Stone--have a lithic contact of limestone within a depth of 152 centimeters
Wilmonton--have carbonates within depths of 50 to 102 centimeters
GEOGRAPHIC SETTING:
Parent material--35 to 60 centimeters of silty or loamy sediments and the underlying calcareous, loamy glacial till, sediments are Late Wisconsinan in age
Landform--linear and slightly convex slopes on ground moraines
Slope--0 to 4 percent
Elevation--305 to 427 meters above sea level
Mean annual air temperature--7 to 11 degrees C
Mean annual precipitation--700 to 820 millimeters
Frost-free period--130 to 180 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Maxcreek and
Moland soils which are members of a hydrosequence with the Merton soils.
Maxcreek--are at lower landscape positions on flat to concave slopes and are frequently saturated at the soil surface during the wettest portions of normal years
Moland--are at higher landscape positions on convex slopes and do not have a frequently saturated zone at a depth of 1 meter in normal years
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--somewhat poorly drained--a frequently saturated zone occurs at a depth of 0.45 meter in normal years and is considered apparent
Saturated hydraulic conductivity--4.23 to 14.11 micrometers per second (moderately high)
Surface runoff potential--negligible to low
USE AND VEGETATION:
Most areas are cultivated. The principal crops are corn and soybeans. The native vegetation is mixed little bluestem, indiangrass, 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 and Dissected till plains
MLRAs--Central Iowa and Minnesota Till Prairies (103) and Eastern Iowa and Minnesota Till Prairies (104)
LRR M; southeastern Minnesota and possibly northeastern Iowa
Extent--moderate
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Rice County, Minnesota, 1971.
REMARKS:
Particle-size control section--the zone from a depth of 25 to 100 centimeters (A, Bw1, 2Bw2, 2Bw3, 2Bw4, and 2BC horizons);
series control section--the zone from the surface to a depth of 150 centimeters (Ap, A, Bw1, 2Bw2, 2Bw3, 2Bw4, 2BC, and 2C horizons).
Diagnostic horizons and features recognized in this pedon include:
mollic epipedon--the zone from the surface to a depth of 41 centimeters (Ap and A horizons);
cambic horizon--the zone from a depth of 41 to 91 centimeters (Bw1, 2Bw2, 2Bw3, and 2Bw4 horizons);
udic moisture regime.
Cation-exchange activity class is inferred from lab data from similar soils in the surrounding area.
Taxonomy version--Keys to Soil Taxonomy, ninth edition, 2003.