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~~}Weed Control Schedule: Timing of weed control shall be based an the most effective <br />control of the target weed species see 4.2.3 below}. Far example if false brome appears <br />on the site, the contractor shall make every attempt to eradicate it before the plants go to <br />seed. On the other hand blackberry control is found to be the most~effective in the fall as <br />the plants draw nutrients back into the roots. <br />~2}Weed Control Locations. Areas to be weeded are the same as the planting areas <br />shown on Map 1. The City and Contractor shall discuss the boundaries of the weed <br />control area during the pre-project field visit. <br />~3}Target Weeds. Following is a fist of the target species and the percent cover that will <br />be allowed for each of these species: <br />Armenian blackberry ~Rubus armenlacus}. This species is prevalent throughout <br />the Delta Ponds area and will likely be the primary target of weed cantrol efforts. <br />Blackberry shall not exceed ~4% cover within the project area. <br />Scotch broom ~Cyflsus scoparlus}. This species is present in the Delta Ponds. <br />area and readily colonizes disturbed areas, so it may show up within the planting <br />area. All seedling Scotch broom shall be removed so that there is less than 5°/° <br />cover within the project area. <br />False brome ~Brachrpodium sylvaflcum}. False brome is prevalent along the <br />banks of the Willamette River and is a very aggressive grass that tolerates shady <br />conditions. It is unknown whether it is likely to become established. False brome <br />shall be controlled prior to seeding and shall not exceed a percent cover of 5% per <br />1,000 square feet, <br />Meadow knapweed ~Cenlaurea prafiensls}. Meadow knapweed is not present in <br />the vicinity of the Delta Ponds to our knowledge; however it is present at the site <br />from which the riparian bench material was excavated. Efforts were made both to <br />eradicate meadow knapweed at the source site and to remove all top soil; however <br />we are including this species in the contract as a precaution. Meadow knapweed <br />shall not exceed percent cover of 5°/° per 1,000 square feet. <br />~4} Weed Control Methods. Weed control shall be accomplished either using manual <br />methods or careful spot spraying of herbicides. Manual weed control shall be done in such <br />a way as to minimize sail disturbance which can open up new areas for weed seed to <br />germinate. Herbicide application will only be done by a licensed professional using either <br />a glyphosate~based herbicide or Garlon 3A. The surfactant used with these herbicides <br />shall be either Agri-dex or LI-104. This combination is the least harmful herbicide to <br />aquatic life. <br />The Contractor shall submit a description of weed control methods at the pre-construction <br />meeting for approval. Changes to weed control methods shall be submitted to the City for <br />approval at least 5 days prior to implementation. Gontractar shall provide contact <br />information for persons responsible for weed control. <br />5} weed Control Inspections. The determination of a successful cantrol of target weeds <br />within the project boundaries wilC be made at the same time as the giant inspections in <br />September of 2009 and 2010. However, the contractor shall be responsible for timing <br />weed control activities so as to maximize the effectiveness of control as outlined in 4.3.1. <br />~6} Weed Disposal. The contractor shall be responsible for disposal of all weed materiai. <br />Ali vegetative material that does not contain flowering heads or seeds may be dispersed <br />on site to decompose. All flower heads and seed material must be carefully bagged and <br />removed from the site for proper disposal. Care shall be taken to minimize the spreading <br />