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appears that, for now, the woody vegetation in Exclosures 3, 4, and 5 has reach a developmental <br />plateau where competition for space and the race to dominate the largest possible light coliection <br />area is the primary growth pattern which will determine the future chazacter of the trees in each area. <br />But in Exclosure 1 the first stage of competition is in operation where young plants are jostling for <br />position and resources, while competition for light is not of much importance. The density has <br />plummeted in the last year in Exclosure 1, as expected, but in the three older exclosures density <br />changes are probably more due to minor sampling errors than actual changes in the numbers of <br />plants. Exclosure 2 remains somewhat of an anomaly in this series. It is still gaining density, <br />probably as a result of the very severe browsing impact it received in the past. Although the plants in <br />Exclosures 3, 4, and 5 were severely impacted by browsing, it is likely that the woody vegetation in <br />Exclosure 2 was so severely impacted it appeared to be a marginal habitat for cottonwood. In fact, it <br />is quite a good cottonwood habitat and now that it has been protected from cattle it is starting to <br />demonstrate that with significant gains in density. Exclosure 1 was never impacted br grazing to the <br />extent Exclosure 2 was and that difference primarily is due to the lush growth in the wetland adjacent <br />to Exclosure 2. The cattle loved that wetland and its moist forage and readily available water, but <br />because it is 99% herbaceous the cattle never did much damage to that area. But young cottonwoods <br />trying to develop in adjacent habitat were heavily impacted by the cattle as they moved around the <br />entire riparian zone in this area. <br />This year, the dense grass growth that developed as a result of both a good growth year and <br />the removal of cattle seems to have had an impact on reducing the extent of the leafy spurge <br />infestation. The strong competition offered by the bromegrasses in the riparian corridor largely <br />overwhelmed the spurge in many areas where the grass is thick. Spurge even declined noticeably in <br />more open areas where sod forming grasses, mainly western wheatgrass, developed more strongly <br />without the degrading effects of the cattle. However, those areas will not likely see much progress <br />toward elimination of spurge as could be seen in the bromegrass dominated vegetation. <br />The scary Tamarix invasion appeass to have been cut off, although some plants persist. <br />Continued control efforts with this species aze necessary along with making sure no new populations <br />appear downstream or even upstream. <br />In the stream channel realignment area the stream channel has largely recovered. However, <br />the growth in the reconfigured areas, as strong as it is, still shows some signs of vulnerability to <br />scouring flows. Density needs to be higher, but as this yeaz was the first full yeaz it had the <br />opportunity to develop the density is quite good, thanks to a wet winter. Another fair to good year of <br />growth and development should provide some resilience to scouring flows. Of course, no stream <br />channel vegetation is ever completely protected from scouring flows and is always vulnerable to <br />complete destruction if the flood is big enough. But the more growth and the more mature that <br />growth, the larger a flow it takes to destroy the growth. <br />2007 Annual Report Coal Creek Wetland Mitigation Permit DA 198811488 Page 24 <br />