LOCATION SEWARD                  OH+IN MI WI

Established Series
Rev. DRM-RAR
01/2017

SEWARD SERIES

The Seward series consists of very deep, moderately well drained soils that are moderately deep or deep to dense till. These soils formed in 63 to 102 cm of sandy glaciolacustrine sediments or eolian material and the underlying till. They are on beach ridges and dunes on lake plains, wave-worked till plains, water-lain moraines, and till plains of late Wisconsinan age. Slope is typically 0 to 6 percent, but ranges to 18 percent. Mean annual precipitation is about 838 mm, and mean annual air temperature is about 11 degrees C.

TAXONOMIC CLASS: Loamy, mixed, active, mesic Arenic Oxyaquic Hapludalfs

TYPICAL PEDON: Seward loamy fine sand, on a convex, 4 percent slope in a cultivated field at an elevation of 226 meters above mean sea level. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 25 cm; dark grayish brown (10YR 4/2) loamy fine sand, light brownish gray (10YR 6/2) dry; weak fine granular structure; friable; many fine roots; slightly acid; abrupt smooth boundary. 15 to 30 cm thick)

E1--25 to 53 cm; yellowish brown (10YR 5/4) loamy fine sand; single grain; loose; common fine roots; few fine faint dark yellowish brown (10YR 4/4) masses of iron accumulation in the matrix in lower part of the horizon; slightly acid; clear wavy boundary.

E2--53 to 66 cm; brown (7.5YR 4/4) loamy fine sand; weak medium subangular blocky structure; very friable; few fine roots; many fine distinct pale brown (10YR 6/3) iron depletions in the matrix; many fine faint yellowish brown (10YR 5/4) and dark yellowish brown (10YR 4/4) masses of iron accumulation in the matrix; few prominent black (5YR 2.5/1) iron and manganese oxide stains on faces of peds; slightly acid; gradual wavy boundary. (Combined thickness of the E horizon is 20 to 66 cm.)

Bt1--66 to 86 cm; yellowish brown (10YR 5/4) fine sandy loam; weak medium subangular blocky structure; friable; common distinct brown (10YR 4/3) clay films on faces of peds and in pores; many medium faint pale brown (10YR 6/3) iron depletions in the matrix; many medium faint brown (7.5YR 4/4) masses of iron accumulation in the matrix; neutral; abrupt smooth boundary. (13 to 25 cm thick)

2Bt2--86 to 102 cm; dark yellowish brown (10YR 4/4) clay; moderate medium subangular blocky structure; very firm; common distinct dark brown (10YR 3/3) clay films on faces of peds; many fine prominent gray (5Y 6/1) iron depletions in the matrix; many fine distinct yellowish brown (10YR 5/6) masses of iron accumulation in the matrix; 4 percent rock fragments; slightly alkaline; gradual wavy boundary. (0 to 38 cm thick)

2Cd--102 to 203 cm; brown (10YR 4/3) clay; massive with widely spaced vertical fractures; very firm; many prominent gray (5Y 5/1) and greenish gray (5GY 6/1) coatings; few distinct light gray (10YR 7/1) calcium carbonate coatings on faces of vertical fractures; common fine distinct gray (10YR 6/1) iron depletions in the matrix; 4 percent rock fragments slightly effervescent; moderately alkaline.

TYPE LOCATION: Henry County, Ohio; approximately 1 mile southwest of Ridgeville Corners, in Ridgeville Township; about 1,200 feet west and 300 feet north of the southeast corner of sec. 34, T. 6 N., R. 5 E.; USGS Ridgeville Corners, Ohio topographic quadrangle; lat. 41 degrees 25 minutes 42 seconds N. and long. 84 degrees 16 minutes 17 seconds W., NAD 27.

RANGE IN CHARACTERISTICS:
Combined thickness of the A and E horizons: 51 to 81 cm
Thickness of the solum: 89 to 127 cm and typically extends into the till
Depth to till: 63 to 102 cm
Depth to densic contact: 89 to 127 cm
Depth to carbonates: 86 to 122 cm

Ap horizon:
Hue: 10YR
Value: 3 to 5 (6 or more dry); 2 or 3 in thin A horizons, where present
Chroma: 1 to 4
Texture: loamy fine sand, fine sand, or loamy sand
Clay content: less than 10 percent
Sand content: more than 80 percent
Rock fragment content: 0 to 3 percent
Reaction: strongly acid to neutral

E horizon:
Hue: 7.5YR or 10YR
Value: 4 to 6
Chroma: 2 to 6
Texture: loamy fine sand, fine sand, or loamy sand
Clay content: less than 10 percent
Sand content: more than 80 percent
Rock fragment content: 0 to 3 percent
Reaction: strongly acid to neutral

Some pedons have a BA or BE horizon.

Bt horizon:
Hue: 7.5YR or 10YR
Value: 4 to 6
Chroma: 3 or 4
Texture: fine sandy loam or sandy loam, with sandy clay loam in subhorizons less than 8 cm thick in some pedons
Rock fragment content: 0 to 3 percent
Reaction: strongly acid to neutral

2Bt or 2Btg horizon:
Hue: 10YR or 2.5Y
Value: 3 to 5
Chroma: 1 to 4
Texture: clay, silty clay, silty clay loam, or clay loam
Clay content: 27 to 45 percent
Rock fragment content: 1 to 8 percent
Reaction: slightly acid to slightly alkaline

2BC or 2BCg horizon, where present:
Hue: 10YR or 2.5Y
Value: 3 to 5
Chroma: 2 to 4
Texture: clay, silty clay, silty clay loam, or clay loam
Clay content: 27 to 42 percent
Rock fragment content: 1 to 8 percent
Reaction: slightly acid to slightly alkaline

2Cd or 2Cdg horizon:
Hue: 10YR or 2.5Y
Value: 4 or 5
Chroma: 2 to 4
Texture: clay, silty clay, silty clay loam, or clay loam
Clay content: 27 to 42 percent
Rock fragment content: 1 to 8 percent
Reaction: slightly alkaline or moderately alkaline

COMPETING SERIES: This is the Moon series. Moon soils do not have a densic contact within a depth of 127 cm. Other soils in similar families include the Galen, Metea, Ormas, and Prissel series. Galen and Prissel soils do not have carbonates within a depth of 122 cm. Metea soils have less than 27 percent clay in the lower part of the series control section. Ormas soils have more than 8 percent rock fragments in the lower part of the series control section. Galen series classifies as coarse-loamy, mixed, active, mesic Oxyaquic Hapludalfs. Metea, Ormas, and Prissel series classify as loamy, mixed, active, mesic Arenic Hapludalfs.

GEOGRAPHIC SETTING: Seward soils are on beach ridges and dunes on lake plains, wave-worked till plains, water-lain moraines, and till plains of late Wisconsinan age. Slope gradient is typically 0 to 6 percent, but ranges to 18 percent. They formed in sandy glaciolacustrine sediments or eolian material and in the underlying till. Mean annual precipitation ranges from 686 to 1067 mm. Mean annual air temperature ranges from 7 to 13 degrees C. Frost-free period is 135 to 180 days. Elevation is 198 to 305 meters above mean sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the somewhat poorly drained Rimer soils and the very poorly drained Wauseon soils that form a toposequence with the Seward soils, and the Hoytville, Latty, Ottokee, Spinks, and Tedrow soils. The Rimer soils are on less sloping or slightly lower areas, and the Wauseon soils are in depressions, drainageways, and on flats. The very poorly drained, fine-textured Hoytville and Latty soils are on nearby flats and depressions. The somewhat poorly drained Tedrow, the moderately well drained Ottokee, and the well drained Spinks soils are on nearby dunes and ridges that have sandy sediments more than 152 cm (5 feet) thick.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained. The depth to the top of an intermittent perched high water table ranges from 46 to 91 cm (18 to 36 inches) between January and April in normal years. The potential for surface runoff ranges from negligible to high, depending on slope gradient and thickness of the sandy materials. Saturated hydraulic conductivity is very high in the upper part of the solum, moderately low in the lower part of the solum, and low in the substratum.

USE AND VEGETATION: A large proportion is under cultivation, primarily corn, soybeans, wheat, and hay. A relatively small proportion is in pasture or woodland. Native vegetation is mixed hardwood forest, primarily oak, hickory, maple, and beech.

DISTRIBUTION AND EXTENT: Primarily in MLRAs 99 and 111B in northwestern Ohio , southeastern Michigan, and northern Indiana; and to lesser extents in MLRA 139 in northeastern Ohio, MLRAs 97 and 98 in southern Michigan, and MLRA 95B in southern Wisconsin. The type location is in MLRA 99. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: AMHERST, MASSACHUSETTS

SERIES ESTABLISHED: Paulding County, Ohio, 1957.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: from the surface to a depth of 66 cm (Ap, E horizons).
Argillic horizon: from a depth of 66 to 102 cm (Bt, 2Bt horizons).
Densic contact: at 102 cm (top of the 2Cd horizon).
Aquic conditions: low chroma iron depletions in horizons below a depth of 86 cm.

The 06/2002 revision limits the underlying material to till. The previous series concept allowed both till and lacustrine sediments in excess of 35 percent clay. Areas underlain with lacustrine sediments will be correlated as a new series during MLRA update activities. Additional field investigation is needed to collect characterization and supporting data to better define the series concept.

Updates to the pedon description were based on documented field observations. Further evaluation and collection of bulk density data is needed to better define the series concept.

A stratified substratum phase and a deep to till phase have been recognized. These phases will be recorrelated to new series when their areas of use are updated.

ADDITIONAL DATA: Laboratory characterization data from The Ohio State University Soil Characterization Laboratory is available for pedon FT-13; from the Purdue University Soil Characterization Laboratory for pedon S74IN91-6; and from the National Soil Survey Laboratory for pedon S83IN-183-004.

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National Cooperative Soil Survey
U.S.A.