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adverse effect on existing riparian forest, but as most of that forest is on the decline anyway, <br />simply due to old age, even without mining the riparian forest would largely disappear from <br />this valley unless it is provided a means to establish replacements. At some point limited <br />grazing might be allowed to return during specified and highly controlled periods during the <br />year, but year round open range that includes the riparian areas essentially seals the demise <br />of these forests. <br />The best developed wetland vegetation is found in the mitigation enclosures, but the <br />primary differences between the wetlands in the mitigation areas and the wetlands outside <br />the mitigation areas lies in the strong woody vegetation development in the mitigation areas. <br />If the woody vegetation was removed from the mitigation areas the distinction between the <br />wetlands in the mitigation areas and unprotected wetlands would be insignificant. The <br />herbaceous vegetation in the natural wetlands, redeveloped and unprotected wetlands, and <br />redeveloped and protected wetlands are virtually indistinguishable. <br />From a management point of view, to create the very best wetland vegetation as well as <br />replace and maintain the riparian forest units the best course of action would be to allow <br />limited amounts of sand mining in the stream bed to remove as much of the sand source as <br />possible. No extraction should occur below the clay seam and quite possibly no sand extraction <br />should occur at all where the clay seam is not present. Possibly the clay seam could be <br />replaced with upland clays after sand removal, but that is probably an action that comes with <br />considerable risk. Unless the type of clay that is present in the clay seam can be closely <br />duplicated and the clay can be spread at the correct elevation it could actually create more <br />problems than it solves. This should be examined much more closely before being tried on a <br />large scale. But it might made to work with care. <br />Second, all areas where riparian forest is desired should be fenced to keep cattle out of <br />the area for a period of not less than ten years. It is probably not necessary to fence existing <br />forest areas as they are on the decline anyway, even where mining influences are not present. <br />It would probably take at least ten years for developing trees and shrubs to achieve a size <br />where they could maintain themselves against cattle. Fifteen years might actually be a safer <br />number to use. Alternatively, simply judge when grazing might occur again based on the <br />dimensions of redeveloped trees. <br />It is probably not necessary to plant any trees if grazing protection is provided. It would <br />be wiser to put the money that would be spent on trees into better fences. The rate of invasion <br />of both cottonwood and willow is very high and more than adequate to produce the numbers of <br />mature plants needed to replace dying forests. <br />After the young replacement forest has developed grazing should still be restricted to <br />those periods when the least damage will occur. It has been repeatedly shown that riparian <br />cottonwood forest and grazing are compatible, but the grazing period must be restricted to a <br />Coal Creek Wetlands and Wetland Mitigation DA Permit 198811488 August 2003 Page 15 of 23 <br />