2011-07-20_REPORT - M1988044 (2)

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Status report for 2009 species are gaining ground rapidly. On the poorer soils the wheatgrass and needlegrass component is good but not excellent due to the soil being poorer. At this point in time, it appears the two areas will develop somewhat different vegetation, but both will be similar to different types of natural vegetation found in the undisturbed lands. Because of this apparent convergence toward a natural like vegetation it is likely that they will eventually converge into a similar growth. But it is also likely that there will be differences in the vegetation for many years to come. Finally, area 5 was planted in 2009 and is at the top of the hill on gentle topography. Here there seems to be two similar vegetation units developing. The large and gentle swale like areas are developing a growth that is quite similar to the lower elevation two- thirds of area 4. In fact, one would have to say that this part of area 5 and the similar part of area 4 are nearly equal with area 5 just slightly behind area 4. The eastern side of area 5 though contains slopes up to about 5:1 and received a soil cover not unlike the upper portions of area 4. In checking back, this similarity between the two areas is due to the fact that those locations were where soil was stockpiled and when the soil was removed to be spread elsewhere it was natural to leave a bit more of the stockpiled material where the stockpile was located. Physically, it is very hard to avoid this phenomenon. Interestingly, these slopes have followed a development pattern that is fundamentally similar to the upper third of area 4. There were some differences between area 4 and area 5 in their development. Whereas the lower portions of area 4 had fewer weeds than the richer soils, all of area 5 was initially invaded by a very strong growth of tumbleweeds that did not look particularly promising at the time. Further investigation though found a good deal of desirable growth underneath the weeds. Now that it is three years after planting, except for a few local areas on the slopes on the east, that prodigious growth of tumbleweed has all but vanished and has been replaced by a rich grass growth dominated by needlegrasses and wheatgrasses. In short, this area too is developing in a direction that is taking it toward a convergence with the surrounding natural vegetation. The overall conclusions from these observations is that the species included in the seed mixture are very important to the eventual vegetation development and that the seed mixture originally designed to accomplish this has worked admirably. Seeding with more exotic introduced species that are either poorly or not represented in the natural vegetation results in a final growth that may eventually blend with the natural growth but will likely take decades to do so. Therefore, by planting the correct mixture in the first place this convergence and blending process can be reduced to about three to five years instead of at least a decade and usually much longer. The rate and actual pattern of this development, however, is dependent on the habitat characteristics of the location and the type of soil spread. More fertile soil results in a very strong weed component in the first two years. But that weed component declines markedly in the third year and all but disappears in the fourth year. Poor fertility soils result in poor weed growth and reduced initial establishment of desirable, planted and invading species. However, assuming the growth medium isn't so poor that growth even has trouble getting started it appears that these areas can largely catch up with the rich soil locations. One difference does remain for some time though and that is species diversity. Because resources are more abundant on richer soils there is a higher diversity of species after a given amount of time than there is on due July 15, 2010 Page 10 of 13