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materialized, this was the only method available to differentiate between wetlands of different types. The Board of Water and Soil Resources (BWSR) cross-reference table (8420.0549 subp. 2.) indicates that Circular 39 Type 3 wetlands have a"C" water regime modifier. This is an inaccurate cross-reference and the intent of this technical paper is a clarification of the correct interpretation. There is also a common tendency to refer to bottomland hardwoods as Type 7 wetlands. This is also an inaccurate classification. The NWI paper maps do not use the water regime modifier "E" because it was difficult to interpret from the inherent limitations imposed by the remote sensed imagery. Therefore, most if not all Type 3 wetlands were given the designation "C". However, the following discussion will examine and clarify the differences between Circular 39 Types l, 1L, 2, 3, and 7 and the appropriate Cowardin water regime modifying terms. Circular 39 Wetland Types Type 1/1L—Seasonally Flooded Basins or Flats Type 1 wetlands are characterized by soil that is covered with water or is waterlogged during variable seasonal periods but is usually well drained during much of the growing season (italics added for emphasis). These wetlands may be found in upland depressions as well as in overflow bottomlands, i.e. river and stream floodplains. Within floodplains, flooding may occur in late fall, winter or spring. In upland contexts, basins or flats may be water filled during heavy rain events or following spring snow melt. Vegetation types vary greatly according to the season and the duration of flooding. Included within Type 1 are bottomland hardwoods as well as some herbaceous growths. Where the water has receded early in the growing season, smartweeds, fall panicum, tealgrass, chufa, redroot cypress and weeds (such as marsh elder, ragweed and cockleburs) are likely to occur. Shallow basins that are submerged only very temporarily usually develop little or no wetland vegetation (Shaw and Fredine 1956, p30). Since Circular 39 was developed for national application, the description of Type 1 wetlands covers a broad range of geographic contexts hence the reference to winter flooding. Cowardin et al (p. 28) in Table 4 describe Type 1 wetlands as seasonally flooded basins or flats, wet meadow, bottomland hardwoods and shallow freshwater swamps. The water regimes are described as temporarily flooded (A) or intermittently flooded (J). The Minnesota Department of Natural Resources (DNR), within the regulatory framework of the Protected Waters and Public Wetlands framework has added the Type 1 L designator to more clearly clarify the Circular 39 classification method and to allow an accurate distinction to be made between bottomland hardwoods, seasonally flooded non-vegetated or herbaceous vegetated basins and hardwood swamps. The distinction on the basis of hydrology is clear and it was the intent of the DNR to differentiate between forested bottomland hardwoods and non-forested wetlands.