LOCATION OSSIAN                  IA+MN WI

Established Series
Rev. RJK-LDC-RJB
06/2015

OSSIAN SERIES

The Ossian series consists of very deep, poorly drained soils formed in silty alluvium. These soils are on flood plains, low stream terraces, upland drainageways, and lake basins. Slope ranges from 0 to 4 percent. Mean annual air temperature is about 9 degrees C. Mean annual precipitation is about 850 millimeters.

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

TYPICAL PEDON: Ossian silt loam, on a slope of about 1 percent, on a flood plain, in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 23 centimeters; black (N 2/0) silt loam, very dark gray (10YR 3/1) dry; moderate very fine and fine granular structure; friable; common very fine and fine tubular pores; neutral; abrupt smooth boundary.

A--23 to 38 centimeters; black (N 2/0) silt loam, very dark gray (10YR 3/1) dry; moderate fine granular structure; friable; common very fine and fine tubular pores; neutral; clear wavy boundary. [Combined thickness of the A horizon is 30 to 50 centimeters (12 to 20 inches).]

AB--38 to 58 centimeters; very dark gray (10YR 3/1) silt loam, gray (10YR 5/1) dry; moderate fine subangular blocky structure; friable; common very fine and fine tubular pores; common distinct black (N 2/0) organic coats on faces of peds and on surfaces along pores; neutral; clear wavy boundary. (0 to 20 centimeters thick)

Bg1--58 to 81 centimeters; grayish brown (2.5Y 5/2) silt loam; moderate fine subangular blocky structure; friable; common very fine and fine tubular pores; common distinct dark gray (2.5Y 4/1) organic coats on faces of peds and on surfaces along pores; common fine and very fine prominent yellowish brown (10YR 5/6) redoximorphic concentrations; neutral; gradual wavy boundary.

Bg2--81 to 104 centimeters; light olive gray (5Y 6/2) silt loam; weak fine prismatic structure parting to weak fine subangular blocky; friable; common very fine tubular pores; few distinct olive gray (5Y 5/2) coats on faces of peds and on surfaces along pores; common fine dark reddish brown (5YR 3/4) masses of iron-manganese; common fine prominent yellowish brown (10YR 5/6) redoximorphic concentrations; neutral; gradual wavy boundary.

Bg3--104 to 168 centimeters; light olive gray (5Y 6/2) silt loam; weak medium prismatic structure parting to weak fine and medium subangular blocky; friable; common very fine tubular pores; few distinct olive gray (5Y 5/2) coats on faces of peds and on surfaces along pores; common fine dark reddish brown (5YR 3/4) masses of iron-manganese; common fine and medium prominent strong brown (7.5YR 5/8) redoximorphic concentrations; neutral; gradual wavy boundary. (Combined thickness of the Bg horizon is 15 to 127 centimeters.)

BCg--168 to 203 centimeters; light olive gray (5Y 6/2) silt loam; weak coarse prismatic structure; friable; common very fine tubular pores; few fine dark reddish brown (5YR 3/4) masses of iron-manganese; common fine and medium prominent yellowish brown (10YR 5/6) redoximorphic concentrations; slightly effervescent; slightly alkaline.

TYPE LOCATION: Major Land Resource Area (MLRA) 105-Northern Mississippi Valley Loess Hills, Winneshiek County, Iowa subset; about 1 mile east of Ossian; located about 1,630 feet south and 1,306 feet west of the northeast corner of section 12, T. 96 N., R. 8 W.; USGS Postville NW topographic quadrangle; lat. 43 degrees 8 minutes 59.4 seconds N. and long. 91 degrees 43 minutes 44.6 seconds W., NAD 83.

RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon--40 to 60 centimeters
Depth to carbonates--more than 100 centimeters
Clay content in the particle-size control section (weighted average)--18 to 27 percent
Sand content in the particle-size control section (weighted average)--less than 15 percent very fine sand or fine sand
Ratio of coarse silt to fine silt is variable throughout the particle-size control section

A or Ap horizon:
Hue--10YR, 2.5Y, 5Y, or is neutral
Value--2
Chroma--0 or 1
Texture--silt loam or silty clay loam
Clay content--10 to 30 percent
Sand content--0 to 15 percent
Organic matter content--5 to 7 percent
Reaction--moderately acid to neutral

AB or BA horizon (when present):
Hue--10YR or 2.5Y
Value--2 to 5
Chroma--1 or 2
Texture--silt loam or silty clay loam
Clay content--18 to 30 percent
Sand content--0 to 15 percent
Organic matter content--4 to 7 percent
Reaction--moderately acid to neutral

Bg horizon:
Hue--2.5Y, 5Y, or is neutral
Value--4 to 6
Chroma--0 to 2
Texture--silt loam or silty clay loam
Clay content--18 to 30 percent
Sand content--0 to 15 percent
Reaction--moderately acid to neutral

BCg horizon and Cg horizon (when present):
Hue--2.5Y, 5Y, or is neutral
Value--4 to 6
Chroma--0 to 2
Texture--silt loam
Clay content--18 to 27 percent
Sand content--0 to 15 percent
Reaction--slightly acid to slightly alkaline

COMPETING SERIES: These are the Chalmers, Chetomba, Dolbee, Drummer, Dunham, Elpaso, Elvira, Garwin, Gillett Grove, Hartsburg, Madelia, Marcus, Mascoutah, Maxcreek, Maxfield, Maxmore, Patton, Pella, Rushmore, Sable, and Wacousta series.
Chalmers--have a clay content of 12 to 18 percent and have matrix hues of 10YR in the lower third of the series control section
Chetomba--have carbonates within a depth of 100 centimeters
Dolbee--have a mollic epipedon in which the content of organic matter is 2 to 3 percent and have more than 15 percent fine and medium sand in the lower third of the series control section
Drummer--have 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 clay content that averages 27 to 35 percent in the particle-size control section
Elvira--have a sand content greater than 15 percent in the lower third of the series control section
Garwin--have a clay content that averages 27 to 35 percent in the particle-size control section
Gillett Grove--have a sand content of 25 to 45 percent 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 clay content that averages 30 to 35 percent in the particle-size control section
Mascoutah--have a clay content that averages 27 to 35 percent in the particle-size 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 25 to 50 percent in the lower third of the series control section
Maxmore--have a sand content of 30 to 70 percent in the lower third of the series control section
Patton--have a clay content that averages 27 to 35 percent in the particle-size control section
Pella--have carbonates within a depth of 100 centimeters
Rushmore--have carbonates within a depth of 90 centimeters
Sable--have a clay content that averages 27 to 35 percent in the particle-size control section
Wacousta--have carbonates within a depth of 50 centimeters

GEOGRAPHIC SETTING:
Parent material--silty alluvium
Landform--flood plains, low stream terraces, upland drainageways, and lake basins
Slope--0 to 4 percent
Elevation--200 to 400 meters above sea level
Mean annual air temperature--6 to 11 degrees C
Mean annual precipitation--735 to 965 millimeters
Frost-free period--145 to 205 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cannek, Colo, Otter, Richwood, and Rowley soils.
Caneek--are in landform positions similar to those of the Ossian soils, do not have a mollic epipedon, and are calcareous
Colo--are in landform positions similar to those of the Ossian soils and have a mollic epipedon 90 centimeters or more thick
Otter--are in landform positions similar to those of the Ossian soils and have a mollic epipedon 60 to 125 centimeters thick
Richwood--are at higher landform positions, do not have a frequently saturated zone within a depth of 1.8 meters in normal years, and have a sand content of 50 to 90 percent in the lower third of the series control section
Rowley--are at higher landform positions, have a frequently saturated zone at a depth of 0.3 meter during the wettest periods of normal years, and have a sand content of more than 50 percent in the lower third of the series control section

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--poorly drained--these soils are frequently saturated at the soil surface during the wettest periods of normal years and is considered apparent
Saturated hydraulic conductivity--1.00 to 10.00 micrometers per second
Surface runoff potential--low
Flooding--frequent or occasional flooding for brief or very brief periods during the months of February to November in normal years resulting from precipitation events and snowmelt
Ponding--the ponded phase has up to 0.3 meter of water above the surface during late winter and spring in normal years and after heavy precipitation events

USE AND VEGETATION:
Where drained, most areas are cultivated. The principal crops are corn, soybeans, oats, and meadow. Some areas are used for permanent pasture. The native vegetation is big bluestem, western wheatgrass, sedges, blue grama and other species of the tall grass prairie that are tolerant of excessive wetness. See Additional Data section for native vegetative cover in Iowa and Minnesota.

DISTRIBUTION AND EXTENT:
Physiographic Division--Interior Plains
Physiographic Province--Central Lowland
Physiographic sections--Wisconsin Driftless section, Dissected till plains
MLRAs--Eastern Iowa and Minnesota Till Prairies (104), Northern Mississippi Valley Loess Hills (105), and Illinois and Iowa Deep Loess and Drift (108)
LRR M; eastern Iowa, southeast Minnesota, and southern Wisconsin
Extent--moderate

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota

SERIES ESTABLISHED: Green County, Wisconsin, 1969.

REMARKS:
Particle-size control section--the zone from a depth of 25 to 100 centimeters (A, AB, Bg1 and Bg2 horizons);
series control section--the zone from the surface to a depth of 203 centimeters (Ap, A, AB, Bg1, Bg2, Bg3, and BCg horizons).

Diagnostic horizons and features recognized in this pedon include:
mollic epipedon--the zone from the surface to a depth of 58 centimeters (Ap, A, and AB horizons);
cambic horizon--the zone from a depth of 58 to 203 centimeters (Bg1, Bg2, Bg3, and BCg horizons).

Aquic suborder based on matrix color of mollic epipedon and aquic conditions in normal years within a depth of 50 centimeters.

Cation-exchange class is inferred from lab data for similar soils in the surrounding area.

Taxonomy version--Keys to Soil Taxonomy, tenth edition, 2006.

The Ossian OSD site was moved in May of 2002 due to a location description error in the previous description.

ADDITIONAL DATA: In Iowa and Minnesota, 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. Source: Iowa State Office, Natural Resources Conservation Service, Des Moines, IA.

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National Cooperative Soil Survey
U.S.A.