2010-07-15_REPORT - M1988044 (2)

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and being lost to vigorous, erosive stream flows. Put simply, the improved management approach on the property is reaping very significant benefits in the hydrologic balance. RECLAMATION PERMIT STATUS: No changes to the permit were made in the last year and the permit continues in compliance with the plan. 404 PERMIT STATUS: The 404 permit exclosures and other areas included in that permit continued with analysis. Significant gains were seen in Exclosures 1 and 2, but the gains in Exclosures 3, 4, and 5 were less due to the vegetation reaching a density limited plateau in its development. Exclosure 4, which shows a bit less density limitation continued to show some gains but appears to be reaching a density limit. Exclosure 1 continued showing less of the instability that is typical of young vegetation. The growth here, nevertheless, is very dense and may be entering a short duration density limitation. Vegetation zonation and community differentiation appears to be well along in its early stages with cottonwoods and willows tending to establish comfortable boundaries so less early tree-shrub competition occurs. Willows have definitely taken over the wetter areas with cottonwood in the drier, slightly more elevated areas. There is still a good deal of mixing in some locations due to microenvironmental variability. This seems to currently be functioning in a fairly non-conflicting arrangement, but as the trees become larger and shade effects on the shrubs become more prominent, conflict will ensue once again several years from now. In that instance, unless the soils become too wet for the cottonwood, which is entirely possible, the willows will locally lose the battle and relinquish the ground to the trees. The land outside the exclosure and north of the road crossing has shown rapid development of shrubs and trees over the last two summers. In fact, it is so dense in some areas it is hard to find Tamarix invaders that need to be controlled. That, for now, is actually good because it means the native vegetation may well be overwhelming the Tamarix and implementing some of its own control. However, it is not safe to assume the Tamarix will be eliminated by the cottonwood and willow growth because a few years of drought would harm the willow and cottonwood development and allow the Tamarix to gain the upper hand. This does mean that control is somewhat easier because by simply cutting off the Tamarix at the base and keeping them small they can more easily be starved thus reducing the need to use herbicides to kill the Tamarix. In other words, by using density and competition from the native growth the introduced noxious weed can be forced out. This far north which is in the marginal range of Tamarix that approach can be effective even though perhaps several miles down stream a Tamarix invasion could not be controlled that way because the habitat is just more favorable for that species. This is the essence of the technique known as adaptive management - let the site tell you what it needs and then provide that need. The channel relocation area continues to show excellent development and without any heavy flows since the changes were made, it has had an opportunity to establish a great deal of stability. It, as well as the south lowland, could still be negatively affected by a heavy flow, but the impact will be much less significant now that the growth has developed at least a moderately robust density. Exclosure 2 seems to be the one that is showing the slowest development as its water supply is somewhat limited. But even here, gains are significant with both willow and cottonwood making excellent progress. Status report for 2009 due July 15, 2010 Page 5 of 11