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production is expected to decline in the coming few years as has been observed many times over <br />in older reclamation. <br />• <br />Woody Plant Density <br />BACKGROUND DENSITY <br />2009 data from the 2002 reclaimed area estimate the density of woody plants at 85.0 stems per <br />acre, and thus a drop of almost 2x in woody plant density has occurred from the 137.6 stems per <br />acre of the four-year old stage to the 7-year old stage (see ESCO 2006). This trend suggests <br />that the 200 stems per acre background standard could be hard to attain by time Phase III bond <br />release evaluation is appropriate (another three years). <br />In the 2005 reclamation area, the 2009-observed woody plant density level of 1278.8 stems per <br />acre is well above the 200 stems per acre background standard. Comprising this total are big <br />sagebrush, bitterbrush, chokecherry, mountain snowberry, and Saskatoon serviceberry. <br />In the 2007 reclamation area, the 2009-observed woody plant density level of 1420.5 stems per <br />acre is very encouraging for such young revegetation. Comprising this total are big sagebrush, <br />Saskatoon serviceberry, chokecherry, Gambel's oak, and Wood's rose. <br />• Species Diversity and Composition <br />The data illustrated in Figure 5 show that the 2002 reclamation (the oldest) has predictably the <br />smallest amount of relative annual/biennial plant cover of the reclamation areas sampled in 2009 <br />at Yoast Mine. The 2005 reclamation area has slightly more relative annual/biennial forb plant <br />cover than the 2002 reclaimed area. In 2004, when the 2002 reclamation was only two years old, <br />there was approximately five times as much relative cover by annuals and biennials (ESCO <br />2005). In 2006, when the 2002 reclamation was four years old, there was approximately two and <br />a half times as much relative cover by annuals and biennials (ESCO 2007). When the 2005 <br />reclamation was only two years old in 2007, there was approximately four times as much relative <br />cover by annuals and biennials (ESCO 2008). This pattern is repeated in the 2007 reclamation <br />sampled in 2009 which has more than half of the relative cover comprised of annuals and <br />biennials, as is typical of younger reclamation (Figure 5). <br />The distribution of species density by lifeform (Figure 4) shows that the 2002, 2005, and 2007 <br />Reclaimed Areas are more similar to the reference areas than would appear to be the case from <br />the lifeform distribution of relative cover (Figure 5). This is important in that it shows that the <br />basic components of the original ecosystem have indeed been returned and that it is -a matter of <br />. relative proportions of species (and age or community successional status) that separates the <br />14