Item - 2017.PE18.6

The Parks and Environment Committee recommends that:

1.  City Council authorize Urban Forestry staff to implement, where necessary in Wards  3, 4, 5 and 13, an integrated pest management (IPM) program involving aerial and ground spraying of a biological control agent, Bacillus thuringiensis subspecies kurstaki (Btk), injecting individual trees with TreeAzin ™ and mechanical egg mass removal.

2.  City Council direct Urban Forestry staff to consult with Toronto Public Health, Transportation Services and Toronto Police Service to coordinate implementation of the proposed aerial and ground based application of the biological control agent Btk.

3.  City Council authorize the City Solicitor to introduce a by-law to implement a control strategy for European Gypsy Moth infestation through ground based and aerial spraying.

4.  City Council authorize staff to enter into a non-competitive procurement contract with Zimmer Air to conduct aerial spray operations as part of the overall European Gypsy Moth control program.

European Gypsy Moth (Lymantria dispar) is an invasive alien pest that was first found in Ontario in 1969. If left unchecked, populations can grow to outbreak levels which can lead to tree defoliations and ultimately affect the health of the urban forest canopy. The European Gypsy Moth population fluctuates in relation to environmental and biological controls. This pest cannot be eradicated. In 2006, 2007, 2008 and 2013, Toronto implemented control measures when European Gypsy Moth populations attained outbreak levels. Those measures were successful in reducing the population to acceptable levels. Current survey data collected in the fall of 2016 and analyzed in January 2017 indicate European Gypsy Moth population levels have reached outbreak levels in some areas of Toronto, requiring intervention in order to mitigate the impact of this forest health threat. This report presents the results of the survey along with recommended control measures, which include an aerial spray of Bacillus thuringiensis subspecies kurstaki (Btk) in the larger outbreak areas.

At present, aerial spraying is proposed to treat a total of 135 ha of land in Wards 3, 4, 5 and 13. Ground based spraying, tree injection and egg mass removal is proposed for other locations within these wards to treat approximately 40 additional individual trees. This control strategy is expected to reduce the European Gypsy Moth population and expected levels of defoliation, resulting in prevention of tree loss or significant decline.