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youngest of the five exclosures are developing well and reaching toward the goals, but the growth is <br />not yet there. Photographic monitoring is provided for the other three exclosures. <br />In 2010 it was found that Exclosures 1 and 2 continued to show significant gains, but seem to <br />be developing in different directions. New tree seedlings are still found, as would be expected, and <br />this is especially true in Exclosure 1. Exclosure 1 is continuing to shift strongly toward a willow <br />dominance that is probably reducing the growth rates of the cottonwood. Nevertheless, cottonwood <br />still makes significant gains where the local microenvironment is more suited to cottonwood. In <br />wetter soils though willow seems to be winning the competition battle. <br />In Exclosure 2 where willow forms a far less dominant cover and density, cottonwood <br />continues to make strong gains, but once again only in the somewhat drier portion of the exclosure. <br />Here the main competitor with both willow and cottonwood are herbaceous wetland plants that <br />dominate the western edge and the northwestern corner of the exclosure. Elsewhere, cottonwood and <br />willow made significant gains in height, but density did not change very much, if any. <br />This report covers the 2011 growing season. Because of the density of the growth in <br />exclosures 1 and 2, the sampling method had to be changed from a transect method to a more or less <br />randomized point sample method. The problem was that transects became extremely difficult to <br />establish with a straight line as the measuring tape had to be carefully woven through the vegetation, <br />especially in exclosure 1. This resulted in a transect line that would have bends. Thus a different <br />transect than had been used in the past was established that produced a limited amount of <br />comparison with prior data sets. So long as that was the case it was reasoned that the entire exclosure <br />had might as well be sampled. This also allowed for creating a picture of the whole exclosure rather <br />than just repeated transects. Although earlier and new data would not be precisely comparable, at <br />least some comparison could be done. Also, as the project was clearly drawing to a close it was <br />deemed important to examine the entire exclosure to determine whether the general results obtained <br />in the transects held reasonably true for the rest of the exclosure. <br />The 2011 Growing Season: The winter of 2010/2011 was unusual due to the effects from a fairly <br />strong La Nina cycle in the equatorial Pacific. Winter was unusually dry with far below average <br />snowfall through most of the winter. In Denver, only about half of the normal annual snowfall had <br />been received by the end of winter. This is fairly typical of La Nina years. The mountains on the <br />other hand received record snowfall in many places. There was an almost constant northwesterly <br />wind flow which is somewhat downslope and drying. As a result, by the time spring came, the soil <br />moisture deficit was reaching drought conditions. But the La Nina pattern was declining and general <br />atmospheric flow patterns were returning to a more neutral ENSO pattern. <br />By the time May arrived, the precipitation patterns dramatically changed. The prairies that <br />appeared to be headed for a brown summer were drenched in prodigious and prolonged rainfall. The <br />soil moisture deficit plunged as the soils were often saturated with moisture. Growth resumed and <br />2011 Annual Report Coal Creek Wetland Mitigation Permit DA 198811488 Page 2 <br />