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results in a well defined zonation in the vegetation with willow close to the wetter areas and <br />cottonwood in slightly drier and more elevated locations. In this regard, Exclosure 1 is particularly <br />interesting because here cottonwood and willow have almost equal dominance with respect to size, <br />but the willows dominate with respect to numbers and cover. The question here is which species will <br />eventually dominate the site or will they maintain a co-dominance into maturity? The answer is many <br />years away, but it is clear that this exclosure is the most interesting and significant with regard to <br />vegetation dynamics. <br />The point here is that sampling methods and the parameters measured are being adapted to <br />how the vegetation is changing. A parameter considered important early on in the development <br />process may become less important over time and eventually become meaningless. Furthermore, it is <br />also possible that other parameters will appear that become important. For example, if disease begins <br />to attack trees then disease effects need to be measured even though initially disease was of no <br />importance. <br />Each of the exclosures have a discussion, a table that shows the changes in data over the three <br />years of the study duration to this point, and a set of photographs that compare 2008 conditions with <br />the initial conditions in 2006. The emphasis in this report is on how things have changed over the <br />three growing seasons of 2006, 2007, and 2008. <br />EXCLOSUREI- <br />General Description for 2008: This exclosure is located on the west side of the last area <br />to be mined north of the road crossing. The exclosure is long and narrow paralleling the currently <br />indefinite stream channel through this area. The exclosure can be divided into three rather vague <br />zones. The most northerly third is the wettest and has dense growths of baltic rush (Juncus balticus) <br />as well as other wetland species. Woody growth here is mostly willow with some cottonwood, <br />mainly around the edges in drier soils. In all three transects there was a small decline in cottonwood <br />and that probably indicates some stabilization in the cottonwood population. In contrast, cottonwood <br />height increased somewhat, but not dramatically so. <br />In 2007, both the vegetation inside and outside the exclosure increased dramatically <br />compared to 2006. In 2008, there appeared to still be a slight difference between the growth inside <br />and outside the exclosure, but it was also clear that, at least on a visual basis, there had been <br />considerable convergence of the growth in each area. If the summer had been more normal with <br />respect to moisture, the convergence might have been more complete. The important point is that <br />convergence is still progressing. <br />The four sets of photographs to follow demonstrate the tremendous differences between 2006 <br />and 2008. In those photos that show the fence boundary it is apparent just how little difference there <br />is between growth in the exclosure when compared to outside the exclosure. <br />2008 Annual Report Coal Creek Wetland Mitigation Permit DA 198811488 Page 5