2015-12-03_GENERAL DOCUMENTS - M1974070 (5)

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NELSON PIT WEED CONTROL PLAN Introduction This document addresses issues related to weed control at the Nelson aggregate mining site operated by Lafarge West,Inc. Weed control is an issue associated with lands in all stages of the mining process including lands occurring within the permit area that will not be mined, lands that have not yet been mined, disturbed areas that are not yet reclaimed or are part of the operations site, and lands that have been reclaimed. Each of these areas poses different situations relative to weed control. The areas that will not be mined contain primarily perennial weed species that became established on the site during the years when agricultural was the main land use. The primary approach for controlling these weeds will be application of herbicides. Areas within the permit area that have not yet been mined contain weed species comparable to areas that will not be mined,however, weeds in these areas will be best controlled by mowing rather than by herbicide application. Disturbed areas that have not yet been permanently reclaimed such as roadsides,operations areas,product stockpiles and topsoil stockpiles may support a variety of weed species. Control of weeds on these sites will be accomplished using a variety of techniques including mowing, application of herbicides,temporary seeding and timely turnover of products. Reclaimed areas may also support a variety of weed species. Weeds on these areas will be controlled with mowing, application of herbicides, burning, if feasible or combinations of the above treatments. Descriptions of these weed control approaches are included in a later discussion. Weed Species of Concern Typically, the weed species of concern include some or all the following annual and perennial species: Scientific Name Common Name Distributional Growth Form Cirsium arvense Canada Thistle Introduced Perennial Forb Cardaria draba White Top Introduced Perennial Forb Lepidium latifolium Perennial Peppergrass Introduced Perennial Forb Convolvulus arvensis Field Bindweed Introduced Perennial Forb Centaurea diffusa Diffuse Knapweed Introduced Annual Forb Bromus tectorum Cheatgrass Introduced Annual Grass Carduus nutans Nodding Bristle Thistle Introduced Biennial Forb Sisymbrium altissimum Tumbling Hedge Mustard Introduced Annual Forb Descurainia spp. Tansy Mustards Introduced Annual Forb Verbascum thapsus Common Mullein Introduced Biennial Forb All of these species are adapted to disturbed conditions such as those that occur on mining sites or agricultural lands. All of these species were introduced into the region at various times beginning in the late 1800's and have expanded into a variety of habitats. At the Nelson Pit,the primary species of concern is Diffuse Knapweed.