2017-04-12_REPORT - M1980244 (6)

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CC&V: 2016 Weed Management Report infestations from previous years had gone to seed and it is expected that a dense infestation will persist in 2017. Upper and lower sections of Squaw Gulch were treated. Here, extensive infestations of common mullein were apparent, though infestations were found to be less dense compared to infestations treated earlier in the season. Frequent infestations of Dalmatian toadflax Canada thistle, and musk thistle were treated in open space opposite County road 88, and in the drainage way stretching from the sediment ponds. A drainage way coming for Highway 67 and down into Squaw Gulch contains an extensive, densely infestation of common mullein and it was treated. Common mullein was primarily in the rosette stages at the time applications took place. Infestations extended from the drainage way and onto the reclaimed slope below Highway 67 and were partially treated. The lower sections and trail system along the east side of the Bateman Topsoil Stockpile was treated for persistent common mullein infestations. Treatments performed earlier in the season affected common mullein population densities, and this was apparent during the second treatment session. Upper slopes of the Bateman Topsoil Stockpile were not treated due to windy conditions at the time applications took place. Finally, a ground sterilant was applied around the Gold Storage Facility building. Applications targeted existing vegetation, and to suppress new vegetation from emerging post application. Due to mine operations, which ceased applications activities, only approximately 70% of the Gold Storage Facility building perimeter was treated. CONSIDERATIONS AND RECOMMENDATIONS FOR 2017 WEED CONTROL Spot spraying applications of selective herbicides are recommended for treatment of all annual, perennial and biennial noxious weed species growing within the permit boundary at Cripple Creek & Victor Gold Mine. Additionally, noxious weed species identified as establishing outside the mine property should also be treated with herbicides. The optimal time for herbicide treatments would be dependent on the plant's growth cycle and favorable weather conditions. Herbicide applications made to perennial noxious weed species should be performed before the first hard freeze, and while plants are still actively transporting carbohydrates to their roots. Timing of herbicide application is critical, as late season applications are not effective on flowered annual and biennial plants that have started to produce seeds. Herbicides are most effective on actively growing plants, and in most cases, will not terminate weed seed that is starting to or has already developed. Mechanical removal of noxious weed seed is the only means of control during the later stages of the plant's life cycle; however, this is only practical for certain weed species due to their growth characteristics. Removal of Canada thistle and toadflax flower heads would not be a cost- effective means of control at Cripple Creek & Victor Gold Mine. Habitat Management recommends a weed control schedule be implemented in late July and again in late August 2017 to target noxious rosettes, and to treat plants prior setting seed. Herbicide treatments should be concentrated in similar locations until noxious weed infestations are at acceptable levels of control. In the Phase 2 and Phase 5 areas, the AD -R2, Mrs. Beard, and Squaw Gulch area native vegetation is readerly abundant. Controlling noxious weeds in these locations using appropriate herbicides will eradicate weed species and in turn allow more desirable native vegetation to colonize. Areas like the Bateman Topsoil Stockpile which have been aggressively treated during previous herbicide applications should be seeded with a suitable seed mix to maximize growth of desirable plants, which in turn will outcompete noxious weeds and prevent Habitat Management, Inc. 5 December 27, 2016