LOCATION KORONIS                 MN

Established Series
Rev. ROP-CKS-ELB-KDS
07/2012

KORONIS SERIES


The Koronis series consists of very deep, well drained soils formed in loamy glacial till on moraines. The permeability is moderate or moderately rapid. Slopes range from 2 to 40 percent. Mean annual temperature is about 47 degrees F. Mean annual precipitation is about 26 inches.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Mollic Hapludalfs

TYPICAL PEDON: Koronis loam on a 4 percent west facing convex slope in a cultivated field at an elevation of 1120 feet. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 8 inches; very dark grayish brown (10YR 3/2) loam, grayish brown (10YR 5/2) dry; moderate medium subangular blocky structure; friable; about 3 percent gravel; slightly acid; abrupt smooth boundary. (6 to 9 inches thick)

Bt1--8 to 17 inches; brown (10YR 4/3) loam, moderate fine and medium subangular blocky structure; friable; about 4 percent gravel; many thin faint dark brown (10YR 3/3) clay films on faces of peds; slightly acid; clear smooth boundary.

Bt2--17 to 26 inches; dark yellowish brown (10YR 4/4) fine sandy loam, weak medium prismatic structure parting to moderate medium subangular blocky; friable; about 5 percent gravel; many thin faint dark brown (10YR 3/3) clay films on ped faces; moderately acid; clear smooth boundary.

Bt3--26 to 31 inches; yellowish brown (10YR 5/4) fine sandy loam; moderate coarse prismatic structure parting to moderate medium subangular blocky; friable; about 5 percent gravel; many moderately thick distinct dark brown (10YR 3/3) clay films on vertical ped faces and common thin faint brown (10YR 4/3) clay films on other ped faces; neutral; clear wavy boundary. (Combined thickness of Bt horizons is 10 to 30 inches.)

Bk1--31 to 35 inches; light olive brown (2.5Y 5/4) fine sandy loam; few fine prominent strong brown (7.5YR 5/6) Fe concentrations; weak coarse prismatic structure parting to weak medium subangular blocky; very friable; about 8 percent gravel; few moderately thick distinct brown (10YR 4/3) clay films on vertical prism ped faces and common moderately thick prominent dark brown (10YR 3/3) clay films in tubular pores; strongly effervescent; slightly alkaline; clear wavy boundary.

Bk2--35 to 43 inches; light olive brown (2.5Y 5/4) fine sandy loam; few fine prominent yellowish red (5YR 5/8) Fe concentrations; weak medium subangular blocky structure; very friable; about 8 percent gravel; common fine irregular shaped very pale brown (10YR 8/2) threads of soft lime masses; strongly effervescent; moderately alkaline; clear smooth boundary.

C--43 to 80 inches; light olive brown (2.5Y 5/4) fine sandy loam; common fine distinct strong brown (7.5YR 5/6) Fe concentrations; weak thick platy structure; very friable; about 8 percent gravel; strongly effervescent; moderately alkaline.

TYPE LOCATION: Meeker County, Minnesota; about eight miles north of Litchfield; about 1,055 feet west and 2,400 feet north of the southeast corner, sec. 34, T. 121 N., R. 31 W.; USGS Litchfield North quadrangle; lat. 45 degrees 14 minutes 46 seconds N. and long. 94 degrees 33 minutes 3 seconds W., NAD27.

RANGE IN CHARACTERISTICS: Depth to free carbonates ranges from 16 to 36 inches. Rock fragments of mixed lithology comprise 2 to 15 percent by volume of the control section and typically range from 3 to 15 mm. in size.

The Ap or A horizon has hue of 10YR, value of 2 or 3 and chroma of 1 to 3. The dry color has value of 4 or 5 and chroma of 2 or 3. It is sandy loam, fine sandy loam or loam. Reaction is moderately acid to neutral.

An E horizon is present in most uncultivated pedons. It is typically sandy loam, fine sandy loam or loam with a high sand content. Reaction is neutral to moderately acid.

Some pedons have a BA horizon.

The Bt horizon has hue of 10YR, 2.5Y or 7.5YR, value of 3 to 5 and chroma of 3 or 4. The dry color has value of 5 or 6 and chroma of 3 or 4. Redoximorphic features are present in the lower subhorizon in some pedons. It typically is sandy clay loam, sandy loam, fine sandy loam or loam. The argillic horizon has 18 to 24 percent clay and 45 to 65 percent sand. The B/A clay ratio ranges from 1.2 to 1.4. This horizon has thin through moderately thick and few through many clay films on faces of peds and in pores. Coatings of clean sand and silt particles are in the upper part of some pedons. The Bt horizon ranges from moderately acid to neutral. The BC horizon, when present, is slightly or moderately alkaline.

The Bk or C horizon has hue of 10YR or 2.5Y, value of 5 or 6 and chroma of 2 to 4. It is sandy loam, fine sandy loam, or loam with less than 20 percent clay and 50 to 70 percent sand. It lacks redox features in some pedons.

COMPETING SERIES: These are the Angus, Argyle, Baltimore, Bassett, Blooming, Caleb, Dowagiac, Dunbridge, Gara, Lauramie, Lester, Longlois, Lydick, Mohawk, Neda, Newcomer, Oneco, Orwood, Racine, Razort, Sebbo, Taopi, Waucoma, and Winneshiek soils. Angus and Sebbo soils have saturation in the lower third of the series control section. Argyle, Baltimore and Oneco soils have B horizons with 7.5YR or redder hue. Bassett soils are very strongly acid to moderately acid in the upper part of the Bt horizon. Blooming and Racine soils have 15 to 35 percent sand in the upper part of the particle-size control section. Caleb soils have some subhorizons that have more than 45 percent sand in the lower part of the control section. Dowagiac soils have less than 24 percent clay in the lower one third of the particle-size control section. Dunbridge, Waucoma, Newcomer and Winneshiek soils have bedrock at depths above 60 inches. Gara soils average less than 2 percent rock fragments in the control section. Longlois, Lydic and Neda soils have more than 45 percent sand in some subhorizon in the middle part of the control section. Mohawk soils have a higher content of silt and have dark colors in the B horizon which apparently are inherited from dark shale. Orwood soils have no rock fragments in the particle-size control section. Razort soils have less than 30 percent sand in the control section.

GEOGRAPHIC SETTING: These soils generally are on convex slopes of moraines. Slopes range from 2 to 40 percent. The Koronis soils formed in calcareous high sand, low clay glacial till of the Late Wisconsinan Age. Mean annual temperature is about 45 to 52 degrees F. Mean annual precipitation is about 25 to 30 inches. Frost free days range from 125 to 165. Elevations above sea level range from 900 to 1600 feet.

GEOGRAPHICALLY ASSOCIATED SOILS: These include Cordova, Glencoe, Marcellon, and Sunburg soils which formed in similar parent materials and Terril soils formed in loamy colluvium derived from glacial till of mixed mineralogy. The poorly drained Cordova soils are on flats and upper drainageways with a seasonal high water table. The very poorly drained Glencoe soils are mostly in depressions. The somewhat poorly drained Marcellon soils are on slightly depressed elevated flats and gentle slopes. The well drained Sunburg soils are on the most convex peaks and knolls. The moderately well drained Terril soils are on concave toe slopes.

DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate or moderately rapid. Surface runoff is low to high.

USE AND VEGETATION: Used for cropping of corn, soybeans and small grains and hay. Some is in pasture and forest. Native vegetation was savanna or prairie later succeeded by mixed hardwood forest.

DISTRIBUTION AND EXTENT: Associated with, but not confined to, the Alexandria Moraine complex in Central Minnesota. Extent is small.

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

SERIES ESTABLISHED: Stearns County, Minnesota, 1981.

REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic subgroup-zone from the surface to 8 inches (Ap horizon); argillic horizon-zone from 8 to 31 inches (Bt1,Bt2,Bt3 horizons); udic moisture regime. Minor edits only July 2012.


National Cooperative Soil Survey
U.S.A.