LOCATION MCCREATH                IA+MN

Established Series
Rev. RCG-DJP-AAC
03/2013

MCCREATH SERIES


The McCreath series consists of very deep, somewhat poorly drained soils formed in 100 to 150 centimeters (40 to 60 inches) of loess overlying glacial till. The McCreath soils are on broad, nearly level to convex upland areas with little dissection on till plains and on treads and risers on stream terraces. Slope ranges from 0 to 5 percent. Mean annual air temperature is about 8 degrees C (47 degrees F). Mean annual precipitation is about 685 millimeters (27 inches).

TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Aquic Hapludolls

TYPICAL PEDON: McCreath silty clay loam, in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 15 centimeters (0 to 6 inches); black (10YR 2/1) silty clay loam, very dark gray (10YR 3/1) dry; weak fine granular and weak fine subangular blocky structure; friable; slightly acid; clear smooth boundary.

A1--15 to 28 centimeters (6 to 11 inches); black (10YR 2/1) silty clay loam, very dark gray (10YR 3/1) dry; moderate fine granular structure; friable; moderately acid; gradual smooth boundary.

A2--28 to 43 centimeters (11 to 17 inches); very dark brown (10YR 2/2) silty clay loam, dark grayish brown (10YR 4/2) dry, some mixing of very dark grayish brown (10YR 3/2) and very dark grayish brown (2.5Y 3/2) peds near bottom of horizon; moderate fine subangular blocky structure; friable; few fine dark concretions (oxides); moderately acid; gradual wavy boundary. (Combined thickness of the A horizon is 16 to 20 inches.)

Bw1--43 to 64 centimeters (17 to 25 inches); dark grayish brown (10YR 4/2) silty clay loam; moderate fine subangular blocky structure; friable; many narrow, very dark gray streaks, apparently old worm casts and root channels; many fine dark concretions (oxides); many fine and few medium tubular pores; neutral; gradual smooth boundary.

Bw2--64 to 89 centimeters (25 to 35 inches); olive brown (2.5Y 4/3) silty clay loam; weak medium prismatic structure parting to weak fine subangular blocky; friable; many very fine faint brown (10YR 5/3) Fe concentrations; many soft dark accumulations (oxides); many fine and very fine tubular pores; slightly alkaline; gradual smooth boundary. [Combined thickness of the Bw horizon is 30 to 51 centimeters (12 to 20 inches).]

Bk--89 to 112 centimeters (35 to 44 inches); light olive brown (2.5Y 5/4) silt loam; weak coarse prismatic structure parting to weak subangular blocky; friable; common fine faint grayish brown (2.5Y 5/2) Fe depletions and common very fine distinct brown (10YR 5/3) Fe concentrations; common calcium carbonate concretions up to 1 cm in diameter; many soft dark accumulations (oxides); many fine and few medium tubular pores; strongly effervescent; moderately alkaline; clear wavy boundary.[0 to 25 centimeters (0 to 10 inches) thick.]

2BC--112 to 124 centimeters (44 to 49 inches); light olive brown (2.5Y 5/4) gravelly loam; moderate medium prismatic structure; friable; common fine faint grayish brown (2.5Y 5/2) Fe depletions; common fine and medium tubular pores; pebble band with material 3/4 to 3 inches in diameter, most pebbles have carbonate coats about 1 mm thick on lower surfaces; strongly effervescent; moderately alkaline; clear smooth boundary. [0 to 15 centimeters (0 to 6 inches) thick]

2C--124 to 150 centimeters (49 to 60 inches); yellowish brown (10YR 5/4) clay loam; massive; firm; common fine distinct grayish brown (2.5Y 5/2) Fe depletions; few lime concretions; some pebbles and stones; strongly effervescent; moderately alkaline.

TYPE LOCATION: O'Brien County, Iowa; about 3 miles west of Hartley; located about 146 meters (480 feet) north and 540 meters (1,770 feet) west of the southeast corner of section 34, T. 97 N., R. 40 W.; USGS Plessis topographic quadrangle; lat. 43 degrees 10 minutes 20 seconds N. and long. 95 degrees 33 minutes 06 seconds W., NAD 83.

RANGE IN CHARACTERISTICS:
Mollic epipedon thickness--41 to 50 centimeters (16 to 20 inches)
Depth to glacial till--100 to 150 centimeters (40 to 60 inches)
Depth to carbonates--60 to 127 centimeters (24 to 50 inches)
Clay content of the particle-size control section (weighted average)--28 to 35 percent
Sand content of the particle-size control section (weighted average)--less than 3 percent fine sand and sand coarser than fine sand
Additional feature--A coarse textured lag line may occur at the contact of the loess and till

Ap or A horizon:
Hue--10YR or is neutral
Value--2 or 3
Chroma--0 to 2
Texture--silty clay loam
Reaction--slightly acid or neutral

Bw horizon:
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--2 or 3
Texture--silty clay loam
Reaction--neutral or slightly alkaline

Bk or C horizon (when present):
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--2 to 4
Texture--silty clay loam or silt loam
Reaction--slightly alkaline or moderately alkaline
Additional feature--common to many secondary carbonate accumulations in the Bk horizon

2BC horizon (when present):
carbonate coats and/or redoximorphic features occur along prismatic structural faces

2C horizon:
Hue--10YR or 2.5Y
Value--4 or 5
Chroma--2 to 4
Texture--loam or clay loam
Clay content--24 to 32 percent
Sand content--30 to 45 percent
Reaction--slightly alkaline or moderately alkaline
Moist bulk density--1.4 to 1.7 g/cc

COMPETING SERIES: These are the Amana, Breeds, Grantcenter, Joyce, Kingston, Klinger, Klingmore, Larpenteur, Nerwoods, Okabena, Primghar, and Ransom series.
Amana--do not have a loamy glacial till materials in the series control section
Breeds--have a paralithic contact in the lower third of the series control section
Grantcenter--do not have a loamy glacial till materials in the series control section
Joyce--have coarse textured material in the lower third of the series control section
Kingston--do not have a loamy glacial till materials in the series control section
Klinger--have loamy glacial till at depths of 50 to 100 centimeters (20 to 40 inches)
Klingmore: have a bulk density of 1.8 to 2.0 g/cc in the lower third of the series control section
Larpenteur--do not have a loamy glacial till materials in the series control section
Nerwoods--have more than 10 percent sand in the upper loamy mantle
Okabena--have a bulk density of 1.4 to 1.6 g/cc in the lower third of the series control section
Primghar--do not have loamy glacial till materials in the series control section
Ransom--have loamy materials at depths of 60 to 100 centimeters (24 to 40 inches)

GEOGRAPHIC SETTING:
Parent material--100 to 150 centimeters (40 to 60 inches) of loess overlying glacial till
Landform--broad, nearly level to convex upland areas with little dissection on till plains and on treads and risers on stream terraces
Slope--0 to 5 percent
Elevation--305 to 457 meters (1,000 to 1,500) feet above sea level
Mean annual air temperature--7 to 10 degrees C (45 to 50 degrees F.)
Mean annual precipitation--610 to 762 millimeters (24 to 30 inches)
Frost-free period--145 to 170 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Annieville, Gillett Grove, and Sac soils.
Annieville--are on higher landscape positions on more convex areas and are moderately well drained
Gillett Grove--are in lower landscape positions in swales and drainageways and are poorly drained
Sac--are on higher landscape positions on more convex areas and are moderately well drained

DRAINAGE AND PERMEABILITY:
Drainage--somewhat poor - seasonal high saturation occurs in the spring of the year at depths as shallow as 30 centimeters (1 foot) in normal years
Permeability--moderate in the loess and moderate or moderately slow in the glacial till
Surface runoff potential--negligible to low

USE AND VEGETATION: Most areas are cultivated. The principal crops are corn and soybeans with some small grain and hay. The native vegetation is tall prairie grasses.

DISTRIBUTION AND EXTENT: MLRA - Iowa and Minnesota Loess Hills (107A); LRR M; northwestern Iowa and southwestern Minnesota. McCreath soils are of moderate extent.

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

SERIES ESTABLISHED: Clay County, Iowa, 2002.

REMARKS:
Diagnostic horizons and features recognized in this pedon include:
Mollic epipedon - zone from the surface to a depth of approximately 43 centimeters (17 inches) (Ap, A1, and A2 horizons);
Cambic horizon - zone from approximately 43 to 89 centimeters (17 to 35 inches) (Bw1, Bw2);
Calcic horizon - zone from 89 to 112 centimeters (35 to 44 inches) (Bk horizon);
Aquic moisture regime.

This soil was previously included in the Primghar series. Based on MLRA correlation, soils that have 100 to 150 centimeters (40 to 60 inches) of loess over glacial till will be correlated to this series. Soils that have more than 150 centimeters (60 inches) of loess will be correlated to the Primghar series.


National Cooperative Soil Survey
U.S.A.