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is very likely that many of what are considered individual plants in the sampling aze actually part of a <br />single plant. This is not actually a problem as this kind of growth pattern is common naturally in <br />cottonwood that are subjected to frequent intense floods. Along major rivers and streams, trees that <br />have multiple stems originating at the base aze produced by damage to the main shoot and loss of <br />apical dominance. As a result several stems become dominant and the trees grow into what amounts <br />to a very large shrub-like growth form. <br />As the photographs show, growth in this exclosure was robust in 2007. Not only aze <br />maximum heights obviously much greater than 2006, but the leaf density is several times greater. In <br />2006 the pattern of trimmed lower branches that results from grazing was still very evident even in <br />October. But in 2007 that pattern vanished and became essentially a wall of cottonwood leaves. With <br />increased food producing resources it will be interesting to see what happens in 2008 now that good <br />food reserves have undoubtedly been stored and more energy can be directed to increasing height <br />rather than producing leaves where few leaves could previously survive the cattle browsing. <br />Results: Table 3 shows the results of the sampling for 2007 and a comparison with the results <br />in 2006. Sampling in 2007 utilized the same method as was used in 2006, so only minor adjustments <br />needed to be made in the 2006 data results to make a valid comparison between the yeazs. <br />It is evident from the photographs as well as the table that the vegetation did not change <br />much in 2007 other than to become fuller and taller. On the average the cottonwoods gained two to <br />three feet in height and the willows showed compazable gains relative to their ultimate dimensions. <br />As noted above, much of the gain was due to repair of damages incurred during the long period of <br />browsing impact from cattle. <br />Density remains very high, but density here is not actually the density of the plants, other than <br />for willows, but it is shoot density. Most of the "trees" here are actually shoots from a rather few <br />individual trees. It is clear that for trees of this size to have a density of 2,000 to 4,000 individuals <br />per acre is absurd. That said, it is also clear from the data that there are small, new trees that have <br />developed primarily in the understory. This is not unusual, but there is little hope these will ever <br />become trees. Competition or shade effects will likely eliminate the new azrivals. <br />Between 2006 and 2007, a few cottonwoods (shoots) were lost and a total of 6 willows were <br />added. It is unlikely that the loss of the cottonwoods actually occurred, although it is possible. More <br />likely these "losses" were plants that were counted in the 2006 sampling but were slightly outside the <br />transect in 2007. Those kinds of minor sampling errors do occur. But the gain in willows is real. <br />Cover: Cover values for this stand of trees ranged from about 35% to 70% in the woody <br />plant occupied portion of the transect. Although somewhat higher cover will likely develop in the <br />future, those gains will not be a great deal more than what is already seen in the period expected for <br />this program. Crown dimensions will likely expand some as the trees grow and eventually cover may <br />2007 Annual Report Coal Creek Wetland Mitigation Permit DA 198811488 Page 15 <br />