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Grasses dominated the plant cover on this site, contributing 12.07 percent of the total cover or <br />30.27 percent of the total relative cover on this proposed mine disturbance. Perennial forbs <br />contributed a total of 11.27 percent of the total cover and 28.20 percent of the total relative cover <br />on this site. Woody plants contributed a total of 9.93 percent of the total cover or 24.92 percent <br />of the total relative cover on this site. Annuals and biennials contributed 5.27 percent of the total <br />cover or 13.21 percent of the total relative cover of this site. Succulents contributed 1.33 percent <br />of the total plant cover or 3.34 percent of the total relative cover of this site. <br />Sumac was the dominant plant growing on this site, contributing a total of 6.20 percent of the <br />total cover and 15.59 percent of the total relative cover on this site. Bushy Eriogonum <br />(Eriogortum e~ f j`usum), Blue Grams, Sand Dropseed, and Storksbill were the other dominants on <br />this site, contributing 12.37, 11.71, 5.$5 and 5.02 percent, respectively, of the total relative cover <br />on this area. <br />The locations of the 15 cover transects sampled on this site are shown on Map 3B, Mine <br />Facilities Area -Vegetation Transect Location Map. Copies of the individual field data sheets for <br />the plant cover sampling of this site are found in Appendix D -Copies of Disturbed <br />Predisturbance Area -Plant Cover Field Data Sheets. The sample adequacy calculations in Table <br />2, Northfield Mine Sample Adequacy Calculations, document that the number of samples <br />required to describe this site at the 90 percent confidence interval was 12.4 transects. <br />Production. The results obtained from the sampling of the 50 production transects on Disturbed <br />Predisturbance Area are presented in Table 7, Disturbed Predisturbance Area -Production. Total <br />• herbaceous forage production on this location averaged 23.04 g/1/4m2 or 822.2 pounds or air-dry <br />forage per acre. Perennial grasses averaged 16.35 g/1/4m2 and contributed 70.93 percent of the <br />total herbaceous forage and perennial forbs contributed an average of 6.69 g/1/4m2 or 29.07 <br />percent of the forage produced on this site. <br />Shrub Density. The shrub density counts obtained from the 50 belt transects taken in this area <br />are summarized in Table 8, Disturbed Predisturbance Area -Shrub Density. The average shrub <br />density was determined to equal 6.02 shrubs per 100 m2 or 243.6 shrubs per acre. Sumac and <br />Fourwing Saltbush were the most commonly encountered shrubs. <br />The locations of the 50 production bansects sampled on this area are shown on Map 3B, Mine <br />Facilities Area -Vegetation Transect Location Map. Copies of the field data sheets <br />corresponding to this site are found in Appendix F -Copies of Disturbed Predisturbance Area - <br />Shrub Density Field Data Sheets. Examination of Table 2, Northfield Mine Sample Adequacy <br />Calculations, reveals that sample adequacy at the 90 percent confidence interval was equal to <br />70.0 transects. <br />Species Diversity. The percent relative composition or cover values in Table 3, Juniper- <br />Grassland Predisturbance Area -Plant Cover, documents that on this site there were a total of <br />four perennial plants contributing more than five percent to the total relative cover on this site, <br />Blue Grams, Red Threeawn, One-seeded Juniper, and Prickly Pear Cactus; which contributed <br />21.16, 17.35, 9.43, and 7.31 percent, respectively to the total plant cover on this site. Since <br />7 <br />