Title
ADDRESSING APHID INFESTATION COMPLAINTS WITHIN THE URBAN FOREST
COUNCIL STRATEGIC INITIATIVES ADDRESSED:
Preserve and enhance neighborhoods
Address quality of place issues
Provide sustainable water quality and environmental infrastructure
CITY ATTORNEY: N/A
SUMMARY STATEMENT:
In 2012, City Council approved the Tree Board’s (a.k.a. the Parks and Recreation Advisory Board’s) recommendation to suspend chemical applications to control aphids in city birch trees and to pursue a birch tree removal and replacement plan. At the time of this recommendation there were 924 birch trees within the city limits and it would take 10 years or more if the city were to eliminate the birch monoculture that exists along city streets. The recommendation from the department was to reduce the number of birch trees to reach a “tolerable” level of infestation complaints rather than removing all of the trees without an evaluation period. The recommendation included focusing on areas that historically have had the greatest numbers of aphid complaints.
In 2013, City Council approved Ordinance Number 3248 amending the Urban Forest Maintenance Management Plan. After two years of local testing of the chemical application, the City Council concurred with the recommendation from the Tree Board to suspend the use of Imidacloprid (Merit®) as a means of aphid control in birch trees because of its questionable effectiveness. The ordinance amended the chemical application policies contained within the plan and adopted minor revisions to the city tree removal criteria.
In 2013 and 2014, the department embarked on the birch tree removal program, removing approximately 100 birch trees in both years and reducing the number of birch trees from 924 to 701. After the first year of removals there was a reduced number of complaints regarding aphids.
2015 was determined to be an evaluation year to assess the impact of the removal program. There was a marked reduction in the number of calls re...
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