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1 <br /> � 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 classitication. <br /> The NWI paper maps do not use the water regime modifier"E" 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 l, 1L, 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 rnuch 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 floodplains. Within floodplains, flooding may occur in late fall, <br /> � winter or spring. In upland contexts,basins ar flats may be water filled during heavy rain events or <br /> following spring snow melt. Vegetation rypes 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 basins 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 basins or flats,wet <br /> � meadow, bottomland hardwoods and shallow freshwater swamps. The water regimes are described <br /> as temporarily tlooded (A) or intermittently t7ooded (J). <br /> � The Minnesota DepaRment of Natural Resources (D1VR), within the regulatory framework of the <br /> ProCected Waters and Public Wetlands framework has added the Type 1L designator to more clearly <br /> clarify the Circular 39 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 /> 1 Inland fresh meadows(Type 2)wetlands have soil that is usually without standing water during most <br /> � Svoboda Bcological Resources 74�t Brown Road North <br /> Project No.: 2007-081-03 32 Ted Sehultze <br /> � � <br />