2021-01-05_REVISION - C1981022 (3)

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3.0 RESULTS 3.1 QUANTITATIVE EVALUATION: EXTENDED REFERENCE AREA The extended reference area sampled was predominantly a mountain shrub vegetation community dominated by a dense woody canopy with scattered openings and a sparse shrubby and herbaceous understory. Specific vegetation information for the extended reference area is contained in Tables 1, 2, and 4. 3.1.1 Total Vegetation Cover: Extended Reference Area Thirty quantitative cover samples were collected in the extended reference area. Total mean vegetation cover of the extended reference area was 83.40 percent. Graminoids provided 3.27 percent mean vegetation cover, forbs accounted for 6.07 percent mean vegetation cover, and woody species contributed 74.07 percent mean vegetation cover. Total herbaceous vegetation cover, comprising the revegetation success criterion for post-SMCRA reclaimed areas was 9.34 percent (the sum of graminoid and forb vegetation cover). The most frequently encountered species was Quercus gambelli (Gambel's oak), present in 100 percent of the 30 transects sampled for vegetation cover. Symphoricarpos rotundifolius (snowberry) was sampled in 93 percent of all transects. Galium septentrionale (little bedstraw) was present in 57 percent of transects. All other species were encountered in fewer than fifty percent of the vegetation cover transects. Overall, within the extended reference area the perennial deciduous shrub Quercus gambelli, was dominant, contributing 60.73 percent total vegetation cover. Symphoricarpos rotundifolius contributed the second highest vegetation cover, with 8.67 percent total mean cover. The sole remaining significant species was Galium septentrionale contributing 2.13 percent total vegetation cover. Vegetative litter (prior years growth, dead wood, and other biologic organic material) comprised 14.40 percent ground cover overall within the extended reference area. Bare soil comprised 1.20 percent of the ground cover. Rock accounted for 1.00 percent of the ground cover sampled. 3.1.2 Total Herbaceous Production: Extended Reference Area Mean total herbaceous production within the Elk Creek Mine extended reference area in 2019 was 58.07 g/m2 (518 lb/ac). 3.1.3 Species Composition: Extended Reference Area Cover sampling identified three lifeforms and forty plant species within the extended reference area. The lifeforms included six species of perennial grass, one annual graminoid species, sixteen perennial forbs, three annual forbs, one undetermined forb species, and thirteen perennial woody plant species. Of the species encountered within the extended reference area, thirty-one were native and eight were introduced, with one forb undetermined. Perennial species outnumbered annual species by thirty-five to four. All identified herbaceous forb Oxbow Mining, LLC Elk Creek Mine Page 6 2019 Phase III Bond Kelease Po5t-5MCKA Vegetation Report