01-26-2012 Agenda and Packet - Laserfiche WebLink

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EMERALD ASH BORER MANAGEMENT PLAN – DRAFT CITY OF MOUNDS VIEW 2/3 A contracted tree injection process of the chemical "Tree-age" (Emamectin benzoate) would protect these trees for a period of two years. Repeat injections would have to be given to these trees every two years thereafter. Fifteen (15) of these trees (smaller than 12" of diameter) could be treated by City staff with the chemical "Imidacloprid" on an annual basis using the a soil drenching (trough) method. Once these smaller trees reached 12" of diameter, they too would need the aforementioned injection treatment. The 2012 forestry budget includes funds for the injection of green ash trees in parks. The following shows the projected costs of one injection cycle to save these park trees: • 87 green ash trees contractually injected (2 yr. coverage)...$80/tree = $6,970 • 15 green ash trees (<12" dbh) treated by City crew (1 yr. coverage).....$20/tree = $300 Other items to consider: * Average removal cost of one park tree and stump: $300.00 * Average replacement tree cost (2" dia. contracted): $200.00 * Estimated removal and replacement costs for 102 park trees: $51,000.00 EMERALD ASH BORER MANAGEMENT FOR MOUNDS VIEW RIGHT-OF-WAY (BOULEVARD) TREES There are approximately 300 green ash trees on Mounds View right-of-ways (ROW) or boulevards. The average size of these trees is about 15" of diameter as measured at 4.5 ft. above ground (dbh). An estimated 250 of these trees lie on ROW in residential areas and add beauty, shade, stormwater control and property value to the adjacent properties and to the community as a whole. The remaining 50 trees are on commercial or business ROW and will not be a focus of this section's consideration at this time due to low condition factors and somewhat removed placement. Emerald Ash Borer, once established in the City, will likely kill most of these ROW trees within a relatively short period of time. It might benefit the City to spread out this eventuality as long as possible so as to not have to deal with the situation of a large number of trees all dying within a few years of each other. The City must decide on a course of action that could begin in the immediate future (2012/2013). The choices are basically three: 1) Do nothing. Allow the ROW ash trees to remain in place as is with no protection and remove (and maybe replace) infested trees as they die. 2) Remove some of the existing ROW ash trees over time (starting 2012) as they develop non-EAB problems such as storm damage, structural problems and crowding. Then, replace those trees at the end of each year. Grant funds could also be a source of funding to be used for ROW removal and replacement in advance of the larger problem. 3) Inject the ROW ash trees on a two year cycle starting in 2012 (see the following costs). Here are the removal, replacement or injection estimates: * 250 average ROW green ash trees/stumps removed: $300.00/tree X 250 = 75,000.00 * 250 ROW trees replaced: $200.00/tree X 250 = $50,000.00 Total removal and replacement = $125,000.00 * Contracted injection of 250 ROW ash trees (repeated every two years): $80/tree X 250 = $20,000 Related notes: * The City has been removing ("culling-out") damaged or hazardous green ash trees off ROW's averaging 25 trees for the last three years.