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The Board of Water and Soil Resources(BWSR)cross-reference table(8420.0549 subp.2.)indicates <br /> that Circular 39 Type 3 wetlands have a"C"water regime modifier. This is an inaccurate cross- <br /> reference and the intent of this technical paper is a clarification of the correct interpretation.There is <br /> also a common tendency to refer to bottomland hardwoods as Type 7 wetlands. This is also an <br /> inaccurate classification. <br /> The NWI paper maps do not use the water regime modifier`B"because it was difficult to interpret <br /> from the inherent limitations imposed by.the remote sensed imagery.Therefore,most if not all Type <br /> 3 wetlands were given-the designation "C". However,the following discussion will examine and <br /> clarify the differences between Circular 39 Types 1, 1 L, 2, 3, and 7 and the appropriate Cowardin <br /> water regime modifying terms. <br /> Circular 39 Wetland Types <br /> Type 1/1L—Seasonally Flooded Basins or Flats <br /> Type 1 wetlands are characterized by soil that is covered with water or is waterlogged during <br /> variable seasonal periods but is usually well drained during much of the growing season (italics <br /> added for emphasis). These wetlands may be found in upland depressions as well as in overflow <br /> bottomlands,i.e. river and stream floodplain.Within floodplain, flooding may occur in late fall, <br /> winter or spring. In upland contexts,basin or flats may be water filled during heavy rain events or <br /> following spring snow melt.Vegetation types vary greatly according to the season and the duration <br /> of flooding.Included within Type 1 are bottomland hardwoods as well as some herbaceous growths. <br /> Where the water has receded early in the growing season,smartweeds,fall panicum,tealgrass,chufa, <br /> redroot cypress and weeds (such as marsh elder, ragweed and cockleburs) are likely to occur. <br /> Shallow basin that are submerged only very temporarily usually develop little or no wetland <br /> vegetation(Shaw and Fredine 1956,p30). <br /> Since Circular 39 was developed for national application,the description of Type 1 wetlands covers <br /> a broad range of geographic contexts hence the reference to winter flooding. <br /> Cowardin et al(p.28)in Table 4 describe Type 1 wetlands as seasonally flooded basin or flats,wet <br /> meadow,bottomland hardwoods and shallow freshwater swamps.The water regimes are described <br /> as temporarily flooded(A) or intermittently flooded(J). <br /> The Minnesota Department of Natural Resources (DNR), within the regulatory framework of the <br /> Protected Waters and Public Wetlands framework has added the Type 1 L designator to more clearly <br /> clarify the Circular 3 9 classification method and to allow an accurate distinction to be made between <br /> bottomland hardwoods, seasonally flooded non-vegetated or herbaceous vegetated basins and <br /> hardwood swamps. The distinction on the basis of hydrology is clear and it was the intent of the <br /> DNR to differentiate between forested bottomland hardwoods and non-forested wetlands. <br /> Type 2—Inland Fresh Meadows <br /> Inland fresh meadows(Type 2)wetlands have soil that is usually without standing water during most <br /> of the growing season but is waterlogged to within at least a few inches of its surface. Vegetation <br />