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EXCLOSURE2- <br />General Description for 2008: This exclosure is located about a mile, as the stream flows, <br />north and downstream from Exclosure 1. It is located in a large embayment off the main channel and <br />most of it is drier than Exclosure 1. There is a very large and highly productive wetland just to the <br />west of the exclosure and the eastern edge of that wetland encroaches into the western side of the <br />exclosure. That wetland contains very few woody plants and is mostly composed of rushes, bull <br />rushes, a few sedges, and a minor amount of wetland grasses and forbs. <br />The soil here is decidedly more sandy than Exclosure 1, but over most of the site Juncus <br />balticus is still at least moderately abundant. It is apparent there is a fairly good groundwater support, <br />but in some of the more elevated mounds the distance to groundwater diminishes just enough that <br />there is little growth in the pure sand. Cattle impact here has been severe in the past as the cattle <br />frequently grazed in the wetland to the west where there is good forage and available water. Most of <br />the larger woody plants were heavily browsed by the cattle. Those had a good root system, but little <br />top growth. In 2006 (the first year of this study) there were a fair abundance of smaller cottonwoods <br />and willows that showed only minor to moderate browsing impact. <br />In 2007, herbaceous growth increased dramatically over the entire area, mainly as a result of <br />the wet growing season. But woody growth also made considerable progress with a great deal of <br />recovery from previous browsing impacts. Leaf density on the trees and shrubs increased <br />dramatically and with the additional food producing tissues growth of new shoots as well as existing <br />shoots increased some. However, growth was not as prominent as might be expected as the plants <br />were undoubtedly putting a lot of energy into producing more short branches and leaves. <br />In 2008, the overall vegetation development trends seen in 2007 continued, but at a <br />somewhat less dramatic pace. In part this reduced development rate was due to the rapid recovery in <br />the first year after the removal of grazing which increased density up to near the holding capacity. <br />Woody plant growth however showed strong gains, in spite of the dry 2008 growing season. It <br />appears that these plants are starting to tap into the groundwater to a much higher degree. <br />Overall, woody species density here is obviously far less than in Exclosure 1. Here the woody <br />plants are widely distributed over the site, except for the very dry, sandy locations where only <br />scattered grasses are found. <br />Results of Sampling: Table 2 presents the results of sampling for 2008. As stated before, <br />the presentation format is the same as that used for Exclosure 1 and the other exclosures. That is, the <br />emphasis is on a comparison of the three years rather than on the current year. <br />From the table it is evident that the northern half of the exclosure, which is slightly lower in <br />elevation and closer to the water table, shows the greatest amount of woody vegetation. The south <br />side appears to be very marginal habitat with only 2 cottonwoods and no willows noted in 231 feet of <br />2008 Annual Report Coal Creek Wetland Mitigation Permit DA 198811488 Page 8