LOCATION MAXMORE                 IA+MN

Established Series
Rev. ROD-SRS-RJB
06/2015

MAXMORE SERIES

The Maxmore series consists of very deep, poorly drained soils that formed in 100 to 150 centimeters of loess and the underlying glacial till. Maxmore soils are on heads of drainageways and on toe slopes in uplands. Slope ranges from 0 to 2 percent. Mean annual air temperature is about 9 degrees C. Mean annual precipitation is about 825 millimeters.

TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Typic Endoaquolls

TYPICAL PEDON: Maxmore silty clay loam, on a 1 percent slope, in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 20 centimeters; black (N 2/0) silty clay loam, black (10YR 2/1) dry; weak fine subangular blocky structure; friable; common fine roots; common very fine tubular pores; neutral; clear smooth boundary.

A1--20 to 36 centimeters; black (N 2/0) silty clay loam, black (10YR 2/1) dry; weak fine subangular blocky structure; friable; common very fine roots; common very fine tubular pores; neutral; gradual smooth boundary.

A2--36 to 51 centimeters; very dark gray (10YR 3/1) silty clay loam, dark gray (10YR 4/1) dry; weak fine subangular blocky structure; friable; few very fine roots; common very fine tubular pores; neutral; gradual smooth boundary. (Combined thickness of the A horizon is 35 to 60 centimeters.)

Btg1--51 to 66 centimeters; dark gray (2.5Y 4/1) silty clay loam; weak medium subangular blocky structure; friable; few very fine roots; common very fine tubular pores; few distinct clay films on vertical faces of peds; few fine prominent brown (7.5YR 4/4) redoximorphic concentrations; slightly acid; gradual smooth boundary.

Btg2--66 to 91 centimeters; dark gray (2.5Y 4/1) silty clay loam; weak medium subangular blocky structure; friable; few very fine roots; common very fine tubular pores; few distinct clay films on vertical faces of peds; common fine prominent yellowish red (5YR 4/6) redoximorphic concentrations; neutral; gradual smooth boundary.

Btg3--91 to 112 centimeters; dark gray (5Y 4/1) silty clay loam; weak medium subangular blocky structure; friable; common very fine tubular pores; few distinct clay films on vertical faces of peds; common fine prominent yellowish red (5YR 4/6) redoximorphic concentrations; neutral; gradual smooth boundary.

Btg4--112 to 127 centimeters; gray (5Y 5/1) silty clay loam; weak medium prismatic structure; friable; common very fine tubular pores; few distinct clay films on vertical faces of peds; discontinuous stone line consisting of rounded gravel and cobbles, 20 to 150 millimeters in diameter (5 to 10 percent of this horizon); common fine prominent yellowish red (5YR 4/6) redoximorphic concentrations; neutral; gradual smooth boundary. (Combined thickness of the Btg horizon is 40 to 120 centimeters.)

2BC--127 to 203 centimeters; about 50 percent yellowish brown (10YR 5/6) and about 50 percent grayish brown (2.5Y 5/2) loam; massive; friable; few very fine tubular pores; slightly alkaline.

TYPE LOCATION: Major Land Resource Area (MLRA) 104-Eastern Iowa and Minnesota Till Prairies; Black Hawk County, Iowa subset; about 1 mile southwest of Voorhies; located about 300 feet south and 1,700 feet east of the northwest corner of section 29, T. 87 N., R. 14 W.; USGS Reinbeck topographic quadrangle; lat. 42 degrees 19 minutes 31.1 seconds N. and long. 92 degrees 30 minutes 29.3 seconds W., NAD 83.

RANGE IN CHARACTERISTICS:
Mollic epipedon thickness--35 to 60 centimeters
Depth to glacial till--100 to 150 centimeters
Depth to carbonates--100 to more than 200 centimeters
Content of clay in the particle-size control section (weighted average)--27 to 35 percent
Content of sand in the particle-size control section (weighted average)--5 to 15 percent, fine sand and sand coarser than fine sand
Special feature--some pedons have a stone line or thin layer, 2 to 13 centimeters thick of gravelly and sandy materials at the base of the silty or loamy sediments

Ap or A horizon:
Hue--10YR or is neutral
Value--2 or 3
Chroma--0 to 2
Texture--silty clay loam or silt loam
Clay content--24 to 32 percent
Sand content--less than 15 percent
Reaction--strongly acid to neutral

Btg horizon:
Hue--2.5Y or 5Y
Value--4 or 5
Chroma--1 or 2
Texture--silty clay loam - a stone line is commonly at the lower boundary of this horizon
Clay content: 28 to 35 percent
Sand content: less than 15 percent
Rock fragment content--a thin stone line with rock fragments up to 200 millimeters in diameter is present in the upper part of this horizon, lithology is igneous, metamorphic and dolomitic
Reaction--strongly acid to neutral

2BC or 2C horizon:
Hue--7.5YR to 5Y
Value--4 to 6
Chroma--1 to 8
Texture--loam
Clay content--18 to 27 percent, mean of 22 percent
Sand content--35 to 65 percent, mean of 44 percent
Reaction--slightly acid to moderately alkaline
Rock fragment content--2 to 12 percent, igneous, metamorphic and dolomitic
Moist bulk density--1.75 g/cc to 1.90 g/cc

COMPETING SERIES: These are the Chalmers, Chetomba, Dolbee, Drummer, Dunham, Elpaso, Elvira, Garwin, Gillett Grove, Hartsburg, Madelia, Marcus, Mascoutah, Maxcreek, Maxfield, Ossian, Patton, Pella, Rushmore, Sable, and Wacousta series.
Chalmers--have a clay content of 12 to 18 percent in the lower third of the series control section
Chetomba--have carbonates within a depth of 102 centimeters
Dolbee--does not have rock fragments in the series control section
Drummer--are stratified with a sand content of 15 to 80 percent in the lower third of the series control section
Dunham--have a sand content of 75 to 98 percent in the lower third of the series control section
Elpaso--have a sand content of 2 to 45 percent in the lower third of the series control section
Elvira--does not have rock fragments in the series control section
Garwin--have a sand content of less than 15 percent in the lower third of the control section
Gillett Grove--have a moist bulk density range of 1.6 to 1.8 g/cc in the lower third of the series control section
Hartsburg--have carbonates within a depth of 90 centimeters
Madelia--have carbonates within a depth of 100 centimeters
Marcus--have a sand content of less than 15 percent in the lower third of the control section
Mascoutah--have a sand content of less than 7 percent in the lower third of the control section
Maxcreek--have a sand content greater than 15 percent in the lower third of the series control section
Maxfield--have a sand content of 35 to 65 percent within a depth of 100 centimeters
Ossian--have a sand content of 0 to 15 percent in the lower third of the series control section
Patton--are stratified with a sand content of 7 to 25 percent in the lower third of the series control section
Pella--have carbonates within a depth of 100 centimeters
Rushmore--have carbonates within a depth of 90 centimeters
Sable--have a sand content of less than 8 percent in the lower third of the control section
Wacousta--have carbonates within a depth of 50 centimeters

GEOGRAPHIC SETTING:
Parent material--100 to 150 centimeters of loess and underlying glacial till
Landform--heads of drainageways and on toe slopes in uplands
Slope--0 to 2 percent
Elevation--198 to 335 meters
Mean annual air temperature--7 to 12 degrees C
Mean annual precipitation--750 to 900 millimeters
Frost-free Period--130 to 186 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dinsmore, Garwin, Klingmore, and Maxfield soils.
Dinsmore--are on higher landscape positions on convex ridges and side slopes and have a frequently saturated zone within a depth of 1 meter in normal years
Garwin--are in landscape positions similar to those of the Maxmore soils and have a sand content of less than 15 percent in the lower third of the control section
Klingmore--are on slightly higher landscape positions on convex side slopes, head slopes and nose slopes and have a frequently saturated zone within a depth of 0.3 meter in normal years
Maxfield--are in landscape positions similar to those of the Maxmore soils and have a sand content of 35 to 65 percent within a depth of 100 centimeters

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--poorly drained--these soils are frequently saturated at the soil surface during the wettest portions of normal years, both perched and apparent saturation can occur on this soil based on precipitation frequency and intensity during a given period of time
Saturated hydraulic conductivity--4.23 to 14.11 micrometers per second (moderately high) in the loess and 0.01 to 1.41 micrometers per second (low or moderately low) in the underlying glacial till
Surface runoff potential--negligible or very low

USE AND VEGETATION:
Most areas are cultivated. The principal crops are corn and soybeans. The native vegetative cover is a herbaceous wetland community commonly inhabited with Bluejoint Grasses, Fowl Bluegrasses, Green Muhlies, Fox Sedges, Field Sedges, Dudleys Rushes, Torreys Rushes, Swamp Milkweeds, False Sneezeweeds, False Asters, New England Asters, White Panicled Asters, and Wild Mints.

DISTRIBUTION AND EXTENT:
Physiographic Division--Interior Plains
Physiographic Province--Central Lowland
Physiographic section--Dissected till plains
MLRA--Eastern Iowa and Minnesota Till Prairies (104)
LRR M; northeastern Iowa and southeastern Minnesota
Extent--small

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana

SERIES ESTABLISHED: Black Hawk County, Iowa, 2001.

REMARKS:
Particle-size control section--the zone from 25 to 100 centimeters (A1, A2, Btg1, Btg2 and Btg3 horizons);
series control section--the zone from the surface to a depth of 150 centimeters (Ap, A1, A2, Btg1, Btg2, Btg3, Btg4, and 2BC horizons).

Diagnostic horizons and features recognized in this pedon include:
mollic epipedon--the zone from the surface to a depth of 51 centimeters (Ap, A1, and A2 horizons);
cambic horizon--the zone from 51 to 127 centimeters (Btg1, Btg2, Btg3, and Btg4 horizons);
aquic subgroup--low chroma in zone from 51 to 66 centimeters (Btg1 horizon);
aquic moisture regime.

The Btg horizon does not meet the 1.2 percent increase in clay requirement for an argillic horizon;

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.

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National Cooperative Soil Survey
U.S.A.