2012-03-09_REPORT - C1981019 (9)

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Tables B1 — B4 and Charts B3 — B6 display the average and relative ground cover from the sampling efforts for 2009 (plots 1 — 5) and 2011 (plots 6 — 10). When comparing charts on the same page, it is important to note that plots in a vertical line with one another are the same treatment, e.g. plot 1 and plot 6 both have 18 -20 inches of topsoil and seed mix 1 and 2, plot 2 and plot 7 have 6 inches of topsoil and seed mix 1, and so forth. However, it is also important to remember that while these charts are presented in a way that allows direct comparison, the data were collected in different years and are not a direct comparison of ground cover between all plots for the previous growing season. There are similarities between the two years and groups of plots. The topsoiled plots (1 — 3 and 6 — 8) have greater overall perennial cover than the non - topsoiled plots inside the fence and, for the most part, outside the fence as well. The composition of perennial cover varies greatly between inside and outside the fence. Inside the fence, shrubs and sub - shrubs tend to dominate. Outside the fence, however, perennial grass and forb (herbaceous) cover generally meets or exceeds shrub cover. Charts B -15 — B -34 show the relationships between herbaceous and shrub cover for each individual plot over the years 2006 — 2011, along with woody plant density for each plot. Plot 2 consistently runs contrary to the overall trend, as seen in Charts B -7 and B -8 and is not entirely unexpected since this treatment was not seeded with any grass species. Plot 7 demonstrates a similar response (Charts B -9 and B -10), but herbaceous cover outside the fence still exceeds shrub cover. This difference may be due to unintended effects from the fence, as discussed earlier. Plots 2 and 7 are both in treatment 2, which was the only treatment not seeded with any grass species, and has consistently had the highest woody plant density numbers (Charts B -11 and B -12), which can therefore explain why shrub cover would be greatest in this treatment. Woody plant density, for the most part, does not express quite the same level of fluxuation as cover variables. Over time, inter- and intra- specific competition has caused woody plant density to decline toward relative stability or equilibrium. Currently, all treatment plots greatly exceed the woody plant density standard set by TR -72. In analyzing the data and extrapolating results it's important to consider the post- mining land use for the unit. If the desired outcome for reclamation is to maximize woody plant density, then treatment 2 (six inches of topsoil and seed mix 1) appears to provide suitable procedures for establishing resilient shrubs. This hinges, of course, on the timing and availability of adequate precipitation. However, if establishing sage - grouse brood rearing habitat (Braun et al. 2005) is more important, then it appears that treatment 3 may provide better habitat than the other treatments. Treatment 3 appears to have sufficient shrub and perennial plant cover to meet sage - grouse brood rearing habitat requirements as well as pass reclamation success criteria. It also exhibits the greatest plant diversity among all treatments (Tables B -3 and B -4). Cedar Creek Associates, Inc. B - 5 Colowyo Mine 2011 Revegetation Monitoring Report