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Annual grasses <br />Perennial forbs /Subshrubs <br />Perennial cool season grasses <br />Woody plants are not included because they are addressed by separate standards as <br />discussed below. <br />Alternative Test D: Assessment of the Presence of Native Species - The third alternative <br />assessment of the species diversity of the reclaimed land makes direct reference to the <br />presence of native western North American plant species in the reclaimed area. <br />Total cumulative # of native species* >_ avg. reference area native species density (# <br />species / 100 square m) <br />*in the adequate sample of the reclaimed area and including alfalfa and / or cicer milkvetch <br />which have often been included in seed mixes as nitrogen — fixers in light of the lack of <br />suitable and available native nitrogen - fixers. <br />Comparing the cumulative number of species in what would often be twenty 100 square in <br />samples in the reclaimed area to the average density in the reference areas actually <br />compares a native species density per 2000 square ms in the developing revegetated area to <br />the native species density per 100 square ms in the long established native areas. As such <br />it allows a forward - looking assessment of the developing presence of native species <br />without necessitating the passage of the likely requisite several to many decades for them <br />to "fill -in" and actually achieve a density per random 100 square in equal to that occurring <br />in the undisturbed areas. <br />Shrub Evaluation - Shrub density sampling will be conducted in the reclaimed area using <br />the belt transect method in accordance with Section 4.15.11(c)(i). Belt transects are 2 in x <br />50m in dimension and are randomly oriented from the sample point origin. <br />Sample adequacy (15 minimum samples) for the belt transect method will be evaluated <br />based on the following expression: <br />t <br />n,„ = (dx� <br />Where: <br />n = Minimum Sample Size <br />s = Sample variance (n -1 degrees of freedom) <br />d =Precision (0.10 for cover and production; 0.15 for woody plant density) <br />x =Sample arithmetic mean <br />t = The (a =.10) t -table value for a 1 tail West, n -1 degrees of freedom (infinite degrees of <br />freedom may be used if n >30) <br />n = Sample size <br />This hypothesis will be tested using methods set forth in Section 4.15.11(2). Hypothesis <br />testing may include the null or reverse null approach previously referenced or methods <br />PR -02 2.05.4 -8 06110 <br />