Wetlland classification, identification, delineation-2005

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Modifier"Y" Saturated/Semipermanent/Seasonal(No comparable Cowardin category) Exhibits features of the Saturated,Semipermanent and Seasonal water regimes(Santos and Gauster 1993,pg 32). Modifier"U" Unknown (No comparable Cowardin category) The water regime is not known(Santos and Gauster 1993,pg 32). Discussion Type VIL, The description provided for Type 1 wetlands and the reference to the absence of wetland vegetation in basins that are only flooded very temporarily raises a regulatory question.One of the criteria for a jurisdictional wetland is the presence of hydrophytic vegetation(1987 Manual pp 16-26). Type 1 wetlands often are found in agricultural fields and often are determined to be jurisdictional on the basis of an aerial 35mm slide review; the quality of the slides is poor under the very best of circumstances..The determination of regulatoryjurisdiction is based on normal circumstances or as defined by the COE, being agriculturally cropped 51 out of 100 years (i.e. by inference lacking sufficient hydrology for either 5 or 12.5 percent of the growing season). The Wetland Conservation Act(WCA)determines normalcy as agricultural cropping for 6 out of 10 years (MnRules 8420.0110, Subp 53; 8420.0122 Subp.l, A and B). Typically, normalcy on agricultural lands is determined by the review of the aforementioned low quality 35mm aerial slides and judgments are made as to whether an area is cropped or if the crops are subject to hydrological stresses.The process is highly subjective and can be biased by excessive precipitation that may occur early in the crop growth cycle. Field examination of these areas may indicate the presence of smartweed and some of the other indicated species in seasonally abnormally wet years whereas in normal years, hydrophytic vegetation is absent. It is highly probable that the process of determination of Type 1 wetlands as jurisdictional in many cases is extending beyond the legitimate definition of Type 1 wetlands and the intent of the 1987 Manual. Does a Type 1 basin need to be flooded for 5 percent of the growing season(the lower definitional bound for jurisdictional hydrology)or 12.5 percent(the upper definitional bound for jurisdictional hydrology) in order for hydrophytic vegetation to develop? In practice, the St. Paul District of the Corps of Engineers(COE)(also applied in practice under the Wetland Conservation Act)applies the 5 percent hydrological definition but if that is too short to allow the development of hydrophytic vegetation under normal conditions than the absence of hydrophitic vegetation would make those Type 1 wetlands non jurisdictional.