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. RESULTS <br />Data from the 2000 revegetation monitoring studies at the Seneca it Mine are presented <br />in Tables 1 through 15 contained in Appendix 1. The list of plant species observed <br />during these studies (reclaimed and reference areas) are included in Table 16 in <br />Appendix 2. Seed mixes applied on areas revegetated prior to 1981 and in years 1981 <br />through 1993 are included for reference in Appendix 3. Photographs of representative <br />locations within the reclaimed areas sampled in 2000, as well as photographs of the <br />Mountain Brush and Sagebrush reference areas are included in Appendix 4. Graphic <br />depiction of summaries of vegetation data, precipitation, and total degree days are <br />presented in Figures 1 through 10 of this report. <br />In the cover descriptions below, species listed as "also present' were not "hit" during <br />point-intercept sampling but were present within one meter on either side of the 50 m <br />sample transect line. Cover percentages referred to in the following results as "percent <br />of total vegetation cover" are relative vegetation values. <br />1985 Reclaimed Area <br />(Photographs 1-4) <br />Cover (Table 1) <br />Introduced perennial cool season grasses averaged 54.3 percent of the total vegetation , <br />cover. Smooth brome (Bromopsis inermis) contributed approximately half of this <br />lifeform's total. More than a third was contributed by intermediate wheatgrass <br />• (Thinopyrum intermedium). Minor contributors were redtop (Agrostis gigantea), meadow <br />foxtail (Alopecurus pratensisj, and timothy (Phleum pratense). Native perennial cool <br />season grasses accounted for 19.3 percent of the total vegetation cover. Two-fifths of <br />this was contributed by Baltic rush (Juncus arcticus ssp. ater). Both fieldclustered sedge <br />(Carex praegracilis) and giant wildrye (aka basin wildrye, Leymus cinereus) averaged <br />nearly one-fifth of this lifeform's total. Other minor contributors were foxtail barley <br />(Critesion jubatum), sheep fescue (Festuca brachyphylla ssp. coloradensis), western <br />wheatgrass (Pascopyrum smithii), and bluebunch wheatgrass (Pseudoroegneria spicata <br />ssp. spicata). Introduced perennial (orbs averaged 17.1 percent of the total vegetation <br />cover. This lifeform was comprised mainly of Cicer milkvetch (Astragalus cicer} with <br />more than two-thirds and alfalfa (Medicago sativa) with one quarter of the total. Canada <br />thistle (Breea arvensis) contributed the balance. Native perennial forbs accounted for <br />7.1 of the total vegetation cover. While ten species were found in this area, only <br />standing milkvetch (Astragalus adsurgens var. robustio~ contributed to the total. <br />Introduced annual and biennial forbs averaged 1.4 percent of the total with two minor <br />contributors: yellow sweetclover (Melilotus officinalis) and twolobe speedwell (Pocilla <br />biloba). Native shrubs accounted for 0.7 percent of the total vegetation cover with big <br />sagebrush (Seriphidium tridentatum) being the only contributor. Native annual/biennial <br />forbs and native annual grasses were found in this area, but did not contribute to the <br />total vegetation cover. <br />Total vegetation cover was 39.4 percent. Standing dead, litter, bare soil, and rock cover <br />values were 0.29, 43.71, 14.86, and 1.71 percent respectively. Species density <br />averaged 12.6 species per 100 sq. m. <br /> <br />