Threatened ash trees to receive costlier, less controversial treatment

May 17, 2017 · 0 Comments

By Brock Weir

The thousands of ash trees dotting and lining Aurora’s parks and streets will receive a less-controversial, albeit more expensive chemical treatment in the fight against the Emerald Ash Borer.
Council voted last week to treat trees which, if left untreated, are likely to be decimated by the invasive Emerald Ash Borer beetle, with TreeAzin, after environmentalists and Council members alike sounded the alarm over the possible long-term impacts of the recommended chemical, IMA-Jet, a neonicotinoid.
Council faced a recommendation from staff earlier this month calling on them to approve treatment with IMA-Jet, a more cost-effective treatment from the previously approved TreeAzin as the manufacturer of the product is now recommending yearly treatment with the chemical rather than the previous biennial trunk injection.
“Since the EAB (Emerald Ash Borer) treatment program commenced in 2013, all surviving ash trees on our streets and in our parks have been treated three times,” said Jim Tree, Parks Manager for the Town of Aurora, in his report to Council. “Initially, staff were using the only registered product available for the treatment of the EAB using TreeAzin, which is a biological control product developed through the use of products derived from the Neem tree. Staff had been advised at that time, by the product manufacturer, that the treatment should be administered on a bi-annual basis; therefore, staff proceeding to treat 50 per cent of the candidate trees in the summer of 2013 and the remaining 50 per cent in the summer of 2014.
“In the autumn of 2014, two significant developments had occurred in EAB treatments, being: the manufacturer of TreeAzin revised its recommendation to treat trees in heavily infested areas on an annual basis rather than the previously suggested bi-annual treatments; and staff were alerted to the fact that a new EAB control product, IMA-jet bad been registered for use by Health Canada with the recommended application for this product being annual; however, there was a significant cost reduction associated with the use of this product. Council authorized staff to utilize this product in the control of EAB and concluded that the remaining treatments over the life of the contract be done using this product.”
It was a decision made, however, not without reservation as Councillor Wendy Gaertner, for instance, spoke out about her worries over the use of a neonicotinoid and its impact on the environment, particularly a hit it might have on bee populations.
These concerns were reiterated by Council at the Committee level when faced with the recommendation to continue with IMA-Jet. While Health Canada has noted they have no concerns when the chemical is directed into the tree trunk, Council members were less convinced, likening it to a chemical coursing through one’s veins.
They questioned the environmental impact of leaves fallen from the branches of the treated trees and whether wood chipped and mulched from unsuccessfully treated trees could make a dent as well.
“I was very pleased to hear the discussion around Council with respect to how to treat the Emerald Ash Borer and not to use IMA-Jet,” said Councillor Gaertner at last week’s Council meeting, catching up on the discussions she missed at the May 2 General Committee meeting. “I know from what [Parks and Recreation Director Al] Downey said in the past and some of the research, there might only be a small chance that the neonics are hurting our bee population, but bees fertilize our crops and we need those crops. I was very pleased and I was also satisfied to know that my view about the neonics was accepted by Council.”