2018-01-03_PERMIT FILE - C1981010 (9)

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4 The historic shrub density data were collected using the point -center quarter plotless sampling method, which is no longer a recommended shrub density sampling methodology found in the CDRMS Vegetation Guideline. This does not invalidate the previously collected data, as this sampling methodology was widely used and accepted by the CDRMS in the 1970s and 1980s. Also, this methodology still appears in a number of studies in the scientific literature, but CDRMS dropped this sampling technique because it is slightly more complex to use and interpret than are the belt -transects or quadrat shrub density sampling techniques found in the CDRMS Vegetation Guideline. Examination of the existing Trapper Mine Permit reveals the shrub data are summarized only by total numbers and are not totaled by species in Permit Table 2.3-9 even though these same data are reported by species in Table 2.3-15. Details on the current field sampling and data analysis methods follow 2.2.3.1 Plant Cover In this evaluation, plant cover was evaluated by sampling ten randomly chosen intervals along the outstretched 50 -meter transect tape. At each designated sample position, an inclined, metal ten -point frame one meter in height and width was positioned perpendicular to the tape. Even numbered positions were sampled on the right-hand side of the tape and odd numbered positions were sampled on the left- hand side of the tape in order to further randomize the cover transect samples. Then a sharpened metal rod was dropped through each of ten slots separated by 10 centimeters. Each observation was recorded according to the specific plant species the sharpened rod intersected first as it was dropped. If no plant cover was encountered, then the observation was recorded as to the presence of plant litter, rock, bare ground, lichens or cryptograms intersected at the ground surface. Dead plant material produced in the 2014 growing season that was still attached to a living plant was recorded as part of that living plant, and dead plant material that had fallen to the ground was recorded as litter. The 100 data points collected along each transect were summed for the entire transect for further statistical analysis. Absolute and relative plant cover, species diversity, and plant life forms were determined based upon the observations collected in the sampled plant cover. For each vegetation type sampled, a minimum of 15 cover transects were sampled before sample adequacy was calculated. If the calculated value required additional transects, these were chosen from a pool of additional sites and sampled using the same methodology. 2.2.3.2 Production Three randomly located circular plots measuring one-quarter square meter were clipped along each of the vegetation transects. The production plots were clipped by life form for perennial grasses, perennial forbs, annual grasses, annual and biennial forbs, and noxious weeds. The instructions found in Rule 4.15.11(1)(b) require that only "current annual growth of herbaceous, non -woody, species" are clipped for production; however, the historic production sampling at Trapper Mine used all current annual herbaceous growth in the samples and were not summarized by plant life form. This study replicated these same historic methods to summarize production information. Thus, all annuals, biennials and noxious weeds were also clipped so that the 2014 data could be compared with the previously collected baseline information. However, the 2014 production data also were summarized by plant life forms so these data can be compared to the current standards. As directed by the CDRMS regulations at Rule 1.04 (55) and on page 9 of the CDRMS Vegetation Guideline, half -shrubs were clipped and lumped with perennial forbs in the production sampling. The production samples were usually taken along the same transect used for cover and shrub density sampling. The three clip plots were summed as a single transect datum for later statistical analyses. For each vegetation type, a minimum of 30 production transects were used for initial sample adequacy