1999-05-14_GENERAL DOCUMENTS - C1981017

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contribute to the number of locations where vegetation can become established, slowly bringing stability to these extremely steep slopes. Collection of native seed for use in the revegetation process is appropriate because the species involved clearly demonstrate a capacity to persist over the long term on this site. The European forage species that comprise most of the seed mix specified for acquisition from commercial sources have, as mentioned above, useful early vigor; what is not clear is their ability to persist in the long term. The native purple reedgrass (Calamagrostis purpurascens), groundsel (Senecio atratus), and glaucous aster (Aster glaucodes aka Eucephalus glaucus) specified for on-site collection and inclusion in the sown mix all show clear affinity for occupation of steep slope sites in Coal Basin. Their inclusion not only addresses the need for natives not otherwise commercially available, but also covers the possibility that locally adapted genetic races best adapted to the Coal Basin area are used. The Coal Basin Mine Site Seed Mixture (Table 1. for North Basin Steep Slope Revegetation Project bid solicitation) and the Outslope Seed Mixture (Table 2. of same) are mixes that include species proven in high altitude revegetation. Total seed count is 124.3 seeds per square foot for the former mix and 110.9 seeds per square foot for the latter mix. These are high rates by low altitude standards. However, it is to be remembered that a) these mixes are to be broadcast and b) considering the severity of the environmental conditions (and the consequent low probability of successful catch and establishment for any given individual seed) the rate must be high. It would in fact be suggested that Pennlawn red fescue (Festuca rubra) and Durar hard fescue (Festuca ovina var. duriuscula) be added in the amount of 1.1 and 1.6 PLS pounds per acre, 8