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In fact, it is probably a bit more complex than this and a good deal more examination of <br />different factors at each site would be needed to determine the true relationships. <br />EXCLOSURES 3, 4 AND 5 - <br />As stated earlier, no data analysis was done on these three exclosures in 2011. Therefore, <br />reliance on the photographic documentation is needed. Discussions of changes will be derived from <br />the photographs and from impressions acquired during the annual inspection. <br />A comparison with last year's report photos shows that not much has changed in these <br />exclosures. The trees are a little larger, but other than that the exclosures are very much like they <br />were in 2010. <br />CONCLUSIONS OF STUDIES TO THIS POINT - <br />One of the original stated purposes of this mitigation program was to establish islands of <br />riparian forest from which additional riparian forest could be established in the event grazing was <br />removed at some point in the future. The exclosures, as shown by the data gathered over six <br />sampling periods, have certainly achieved that goal, although Exclosures 1 and 2 are a bit behind the <br />other three exclosures primarily due to age differences. <br />As it turned out, the Colorado Board of Land Commissioners cancelled the grazing lease <br />shortly after this project began. Since that time, the riparian corridor has recovered as if it had been <br />fully enclosed and grazing not allowed. In effect, the exclosures became defined concentrated study <br />locations where the recovery processes could be followed. Actually, the entire project could have <br />ended at that point, the fences removed and recovery allowed to proceed. But all of that is in <br />retrospect. As a result of this project and the examinations performed in the exclosures that were <br />actually not needed a great deal has been learned about the recovery process. Combining this <br />information with yet earlier experiences with both mitigation and mining of the sand resource a <br />complete picture can now be drawn. From that picture it has become apparent what is feasible and <br />what should not be done during the utilization of the riparian corridors of ephemeral streams. So, lets <br />follow that history. <br />Early on in the mining, excavation went quite deep into the streambed. This resulted in a <br />dramatic and rapid decline of the water table on adjacent land. Such a drastic change in the <br />environment resulted in the death of about 3 acres of mature riparian forest. That, in turn, resulted in <br />the earlier mitigation program with the two large exclosures complete with extensive cottonwood <br />replanting to replace the cottonwood lost in the deep mining of the stream corridor. <br />Those exclosures and that mitigation program was successful. But we can now see that the <br />primary factor of that success had little to do with planting cottonwood trees and everything to do <br />2011 Annual Report Coal Creek Wetland Mitigation Permit DA 198811488 Page 12 <br />