LOCATION ONEGA                   MN

Established Series
JJM-RTR-KDS
12/2010

ONEGA SERIES

The Onega series consists of very deep, poorly drained soils that formed in eolian or glaciolacustrine deposits on flats near dunes on glacial lake plains. Slope ranges from 0 to 1 percent. Mean annual air temperature is 4 degrees C. Mean annual precipitation is about 670 millimeters.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, nonacid, frigid Humic Endoaquepts

TYPICAL PEDON: Onega mucky very fine sandy loam, on a linear flat with a slope of 1 percent, on a glacial lake plain, in a cultivated field, at an elevation of about 393 meters. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 15 centimeters; black (10YR 2/1) mucky very fine sandy loam, very dark gray (10YR 3/1) dry; weak fine and medium granular structure; friable; common coarse roots; moderately acid; abrupt smooth boundary. (10 to 15 centimeters thick)

Bg1--15 to 23 centimeters; gray (2.5Y 5/1) very fine sandy loam; weak fine and medium subangular blocky structure; friable; few fine and coarse roots; common fine prominent light olive brown (2.5Y 5/6) redoximorphic concentrations; moderately acid, clear wavy boundary.

Bg2--23 to 81 centimeters; grayish brown (2.5Y 5/2) and light olive brown (2.5Y 5/3) loamy very fine sand; weak fine and medium subangular blocky structure; friable; few fine roots; common fine prominent yellowish brown (10YR 5/6) redoximorphic concentrations; neutral; clear wavy boundary. (Combined thickness of the Bg horizon ranges 50 to 100 centimeters)

Bw--81 to 99 centimeters; light olive brown (2.5Y 5/3) very fine sandy loam; weak fine and medium subangular blocky structure; friable; few fine roots; many medium prominent dark yellowish brown (10YR 4/6) redoximorphic concentrations and many medium distinct gray (10YR 5/1) redoximorphic depletions; neutral, gradual wavy boundary. (Combined thickness of the Bw horizon ranges 0 to 25 centimeters)

Cg--99 to 203 centimeters; gray (2.5Y 5/1) loamy very fine sand; massive; friable; many fine prominent strong brown (7.5YR 5/6) and common fine prominent dark yellowish brown (10YR 4/4) redoximorphic concentrations; neutral.

TYPE LOCATION: Major Land Resource Area (MLRA) 88-Northern Minnesota Glacial Lake Basins; St. Louis County, Minnesota; about 9 miles northwest of Meadowlands; located about 2240 feet south and 2000 feet east of the northwest corner, section 15, T. 54 N., R. 20 W.; USGS Toivola topographic quadrangle, latitude 47 degrees 9 minutes 40 seconds N., longitude 92 degrees 51 minutes 59 seconds W., NAD83.

RANGE IN CHARACTERISTICS:
Depth to carbonates-greater than 203 centimeters
These soils do not have rock fragments

Ap or A horizon:
Hue--10YR
Value--2 or 3, dry 3 to 5
Chroma--1 or 2
Texture--very fine sandy loam, loamy very fine sand or their mucky analogs
Reaction--moderately acid to neutral.

Bg horizon:
Hue--2.5Y or 5Y
Value--4 to 6
Chroma--1 or 2
Texture--very fine sandy loam, loamy very fine sand, or very fine sand
Reaction--moderately acid to neutral
The Bg horizon typically has distinct to prominent redoximorphic concentrations. .

Bw horizon when present:
Hue--2.5Y or 5Y
Value--4 to 6
Chroma--2 or 3
Texture--very fine sandy loam, loamy very fine sand, or very fine sand. Reaction--slightly acid to neutral
The Bw horizon typically has distinct to prominent redoximorphic concentrations and or depletions

Cg horizon:
Hue--2.5Y or 5Y
Value--5 or 6
Chroma--1 to 3
Texture--very fine sandy loam, loamy very fine sand, or very fine sand. Reaction--slightly acid to neutral
The C horizon typically has distinct to prominent redoximorphic concentrations and or depletions.

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING:
Parent material--eolian or glaciolacustrine deposits
Landform--flats on glacial lake plains near dunes
Slope--0 to 1 percent
Elevation--350 to 490 meters above sea level
Mean annual air temperature--3 to 5 degrees C
Mean annual precipitation--635 to 711 millimeters
Frost-free period--95 to 125 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Wawina, Cedar Valley and Cowhorn soils which formed in the same parent material as Onega soils. The Wawina, Cedar Valley and Cowhorn soils form a hydrosequence with the Onega soils. Wawina, Cedar Valley and Cowhorn soils are on nearby convex dunes.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--poorly drained--these soils have a frequently saturated zone within a depth of 0.15 meter below the surface during the wettest periods of years when precipitation is within one standard deviation of the 30 year mean of annual precipitation
Saturated hydraulic conductivity--4.23 to 141.14 micrometers per second

USE AND VEGETATION: Most areas are used for hay or for pasture.

DISTRIBUTION AND EXTENT:
Physiographic Division--Interior Plains or Laurentian Upland
Physiographic Province--Central Lowland Province or Superior Upland
MLRA--Northern Minnesota Glacial Lake Basins (88)
LRR--K; northern Minnesota
Extent--moderate

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

SERIES ESTABLISHED: St. Louis County, Minnesota, 2009. The source of the name is a small village in northwestern Minnesota.

REMARKS:
Particle-size control section--the zone from a depth of 25 to 100 centimeters
Series control section--the zone from surface of the soil to a depth of 150 centimeters

Diagnostic horizons and features recognized in this pedon include:
Ochric epipedon-the zone from the surface to a depth of 15 centimeters
Cambic horizon--the zone from a depth of 15 to 99 centimeters
aquic moisture regime

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

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National Cooperative Soil Survey
U.S.A.