Wed, 30 Jul 2014
With no natural predators, invasive insects can pose a major economic and environmental threat to urban forests. In an effort to stay one step ahead of these destructive pests, the Town of Oakville is taking proactive measures to monitor the movement and populations of insects such as Emerald Ash Borer (EAB), Asian Long-horned Beetle (ALHB) and Gypsy Moth.
“We are conserving and enhancing our tree canopy for today’s residents and future generations,” said Mayor Rob Burton. “Proactive monitoring is a positive and cost-effective system to help us respond quickly and reduce the harmful impact invasive species can have on our trees.”
As part of its monitoring program, the town currently has more than 80 green prism traps hung in town-owned ash trees to monitor EAB infestation levels and to help prioritize and target its EAB management program. Oakville has one of the most aggressive management programs in Canada to combat EAB and is treating 75 per cent of the public ash tree canopy with a bio-insecticide.
The town recently hung ten ALHB traps in select trees in the east area of town. ALHB has not been detected in Oakville. In September of 2013, the Canadian Food Inspection Agency (CFIA) confirmed its presence in an industrial area near Pearson International Airport in Mississauga. ALHB can damage many broadleaf trees, such as maple, birch, elm, poplar and willow. The traps are black with a small cup at the bottom that captures the insect.
Both EAB and ALHB traps are checked every two to four weeks by the town’s consultant BioForest Technologies Inc. The traps do not pose a threat to animals or humans.
The CFIA has also established an ALHB simulation site in Bronte’s Berta Point park at the corner of Lakeshore Road and West River Street. Signs of infestation have been created on trees in the park showing what an actual ALHB infestation may look like to aid Parks and Open Space staff in identifying the insect’s presence, as quick identification is key to controlling any infestation.
The town’s other monitoring projects include an annual gypsy moth egg mass survey. This is done in the fall and winter after the moths have laid their eggs and is used to forecast populations for the following year. Gypsy moths are a concern because the larvae feed voraciously; mostly on the leaves of oak trees. During the larval stage, one gypsy moth caterpillar can eat an average of one square metre of foliage. Gypsy moths were not a major threat in the town this year with low to moderate population numbers.
The town has also initiated an Urban Forest Health Monitoring program in partnership with BioForest Technologies which trains community volunteers on how to monitor trees in their neighbourhood and report any suspicious insect activity.