With its many ash trees, Mississauga’s Rattray Marsh Conservation Area will feel the full impact of the emerald ash borer infestation. Credit Valley Conservation (CVC) is on the front line, managing the effects to one of Mississauga’s prized natural spaces.

The emerald ash borer (EAB) is an invasive forest pest, not native to North America. EAB infest and kill 99.9 per cent of all ash trees they come in contact with. EAB larvae (young) feed just beneath the bark of ash trees and disrupt the movement of water and nutrients. This pest continues to spread north through Ontario by flying from ash tree to ash tree. Rapid spread is caused by transporting firewood, logs and trees from nurseries.

EAB are particularly interested in Rattray Marsh. Almost 80 per cent of its forest cover is made up of ash. These ash trees play an important role in the local ecosystem and provide homes for wildlife. The area is home to many beautiful, mature ash trees that line the trails and boardwalk.

“EAB are here. They’re in the surrounding neighbourhoods and in Rattray Marsh,” said Jon MacMull, Marketing & Communications Specialist for CVC. “Our immediate concerns are the safety of conservation area visitors, protecting unaffected ash trees from EAB and replanting for the future.”

Trees that are infested with EAB will decline and eventually fail. CVC staff have identified declining trees that pose a risk to the public and neighbouring properties and are pursuing an ash tree management plan. This will involve inoculating healthy trees against the effects of EAB and removing trees that cannot be saved. Both methods require that CVC staff close portions of trails at the conservation area because of potential safety risks to the public.

“In the months and years following ash tree management, we’ll plant new trees to help the conservation area recover and we want the community to be part of that process,” said MacMull. “Some ash trees that are cut will be left on the forest floor to create wildlife habitat and return nutrients back into the soil.”

CVC is trying to inoculate as many ash trees as possible against the effects of EAB. Maintaining a healthy population of ash trees is important for the local environment. Only healthy, unaffected trees can be inoculated. CVC determines the best candidates based on a number of criteria. Inoculating one tree costs $200 on average. Healthy trees need to be inoculated once every two years. This works out to only 27¢ a day to save one ash tree.

“We’re calling on everyone who visits Rattray Marsh to do what they can to save our ash,” said MacMull. CVC and the Credit Valley Conservation Foundation have launched a campaign to raise funds to help preserve the forests at Rattray Marsh Conservation Area. Donations will be used to inoculate ash trees and plant new trees for the future. Visit www.creditvalleyca.ca/eab and click the link that says save our ash.

CVC is hosting an Ash Tree Management and EAB Community Meeting for residents living near Rattray Marsh. The meeting takes place Monday April 28 from 7 to 9 p.m. at Green Glade Senior Public School, 1550 Green Glade, Mississauga.

Inoculating an ash tree to protect it from emerald ash borer. Photo courtesy of BioForest Technologies Inc.


Conservation Authorities are a provincial/municipal partnership. CVC was established by an act of the province in 1954 with a mandate to protect all natural resources other than minerals in the area drained by the Credit River. We have been working for 60 years with our partner municipalities and stakeholders to protect and enhance the natural environment of the Credit River Watershed for present and future generations.

Media Contact:
Jon MacMull
Marketing & Communications Specialist
Credit Valley Conservation
905-670-1615 ext. 385
[email protected]

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