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DISCUSSION <br />Over all nine shrub concentration areas sampled, shrub density averaged about 1875 stems per <br />acre. Inasmuch as the permit-specified standard for these areas is 2000 stems per acre, the <br />' density extant as of 2004 (1875 stems per acre) exceeds 90% of the standard (0.9 x 2000 = 1800 <br />stems per acre). The range of densities observed was 243 stems per acre (Block B) to 6945 <br />' stems per acre (Block C). <br />For the most part the main shrub species contributing to the measured densities is big sagebrush <br />' (Seriphidium tridentatum). One notable exception is Block G, where a substantial density of <br />Woods rose (Rosa woodsii) has developed since this area was sown in the early 1990's. This <br />' block was seeded extremely heavily in 1993 and initial results showed extremely high densities of <br />five species including serviceberry (Amelanchier alnifolia), chokecherry (Padus virginiana ssp. <br />' melanocarpa), bitterbrush (Purshia tridentata), Woods rose and mountain snowberry <br />(Symphoricarpos rotundifolius). The total 1995 density in this block was over 33,000 stems per <br />acre (ESCO 1996). As of 2004, chokecherry and serviceberry have disappeared and relatively <br />' low amounts of bitterbrush and snowberry (along with big sagebrush) remain, but Woods rose is <br />the only species that has persisted in large numbers. <br />1 Also notable is the survival of 68 stems per acre of quaking aspen (Populus tremuloides) in Block <br />' B. Rosa spp. in Block I are likely to be the result of seeding material labeled as Woods rose that <br />was really a mixture of species. Certain "wild" rose collection sites were the sites of early <br />experiments in wildlife range enhancement where a variety of rose species were sown. The <br />t resulting vigorous stands of roses on these public land sites in Utah are particularly attractive to <br />seed collectors. The collected seed lots are commonly entirely attributed to Woods rose although <br />' much is not actually such (Richard Dunne, Wind River Seed, personal communication). <br />Literature Cited <br />ESCO Associates Inc. 1996. 1995 Revegetation Monitoring Report, Seneca II Mine and Seneca <br />' II-W Mine, Routt County, Colorado. Prepared for Seneca Coal Co., Hayden, CO. <br />