Wetland Classification/Ident/Delineation

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Morrisontown quadrangle; lat. 44 degrees 7 minutes 57 seconds N. and long. 93 de�rees 26 minutes 45 seconds W., NAD27. RANGE IN CHARACTERISTICS: Depth to free carbonates ranges from 22 to 55 inches. The thickness of the mollic epipedon ranges from 10 to 18 inches. Rock fragment content is 1 to 8 percent by volume throughout and is of mixed lithology. The A horizon has hue of l OYR, value of 2 or 3, and chroma of 1 or 2. The A horizon is clay loam, loam, silt loam, or silty clay loam. It has 20 to 30 percent clay. It is moderately acid to neutral. An E horizon as much as 3 inches thick is in some pedons. The AB horizon has characteristics similar to the A and the Bt. The upper part of the Bt horizon has hue of lOYR or 2.SY, value of 3 to 5, and chroma of 2 or 3. The lower part of the Bt horizon has a hue of 2.SY, value of 4 or 5, and chroma of 2 to 4. The Bt horizon is mostly clay loam or loam. The argillic horizon averages between 24 and 35 percent clay and from 15 to 40 percent fine sand or coarser. The Bt horizon is strongly acid to slightly acid in the upper part and strongly acid to neutral in the lower part. The bulk density ranges from 1.30 to 1.45 gm/cc. Some pedons have a BC or Bk horizon. The C horizon has hue of 2.SY or SY, value of 4 to 6, and chroma of 2 to 4. It is loam or clay loam. It is slightly alkaline or moderately alkaline. The bulk density ranges from 1.45 to 1.60 gm/cc. COMPETING SERIES: These are the Andres, Aurand(T), Aztalan, Crane, Darr-o�h, Gilboa, Houstei�ac��;r(T), La Ho�ue, Marcellon, Mokena, Nachusa, Nenno, Ncwhaven, Odell, Protivin, Tidcrishi, Vig�3r, and Wilmer series. The Aurand(T) and Tiderishi series are presently not in the OSD file. The Andres, Aztalan, and Mokena soils have silty clay loam lower B and C horizons. Aztalan soils also have hue of 7.SYR in the B and C horizons. Crane soils have more than 8 percent rock fra�nents in the lower part of the argillic horizon. Darroch soils have C horizons of stratified silty and sandy sediments within the series control section. Gilboa soils have silt loam and silty clay loam in the upper part of the series control section. Houstenader soils have 30 to 40 percent gavel in the lower third of the series control section. La Hogue soils have less than 20 percent clay in the lower part of the series control section. Marcellon soils have less than 24 percent clay in the argillic horizon. Nachusa soils do not have rock fragments in the upper part of the series control section. Nenno soils have more than 8 percent rock fragments in the lower part of the series control section. Newhaven soils do not have free carbonates in the series control section. Odell soils have hue of lOYR in the lower B and C horizons and higher chroma in the upper B horizon. Protivin soils have bulk density greater than 1.60 gm/cc in the lower part of the series control section. Vigar soils have a mollic epipedon greater than 24 inches thick. Wilmer soils have more than 40 percent fine sand or coarser in the argillic horizon. GEOGRAPHIC SETTING: The Le Sueur soils have slightly concave, plane, or slightly convex slopes on moraines within the Des Moines lobe and Grantsburg sublobe of the Late Wisconsin glaciation. They formed in a calcareous, loamy till. Slopes range from 1