Emerald ash borer
CORNWALL, Ontario – Every ash tree in the city could be dead in just a matter of 15 years, according to a report presented to city councillors Monday night.
Cornwall is directly in the cross hairs of the Emerald Ash Borer, a non-native wood-boring beetle that has been plaguing forests in North America.
“It has killed literally millions and millions of trees in the eastern United States, Ontario and Quebec and it shows no sign of slowing down,” Philip van Wassenaer, an industry expert, told city councillors.
The insect lays eggs just below the bark layer of the tree, and when the larvae hatch they begin to feed on parts of the tree that conduct nutrients – resulting in its death.
The deaths of all the ash trees will result in more storm runoff, a significant decrease in available shade and danger from falling limbs and branches.
“When they die they have a decay in their roots very quickly…they start to fall over as whole trees,” said van Wassenaer, who was tapped by the city to catalogue the ash trees within Cornwall. “In most areas, once the pest is there 98 per cent of the trees will be gone unless they are treated with some sort of chemical.
“This is the pattern we can expect here in Cornwall.”
In Canada only so-called “trunk-injection” pesticides are allowed to combat the Emerald Ash Borer.
City hall must come up with some kind of management plan, or nearly every ash tree in Cornwall will be destroyed.
Part of that could include the use of pesticides, as well as removal and replacement. But all options come with a cost - between $3.6 and $5.8 million over 15 years.
There is no provincial or federal government help available in the management of Emerald Ash Borer so municipalities have been left on their own.
The insect is believed to have migrated to Canada from Asia via intercontinental transportation. Research into the problem has been limited because it is such a new problem - experts aren't even sure if insecticide injection will save a tree that is only mildly infected.
“It’s a disaster that is happening throughout the province,” said Coun. Glen Grant.
The insect appears focused on ash trees only, said van Wassenaer, but the impact left many city councillors stunned.
“We’re headed for a period of real trouble for our trees,” said Coun,. Bernadette Clement. “It’s a shock.”
City council will meet again on the subject March 24 when specific recommendations for dealing with Emerald Ash Borer will be debated.