Tree disease leaving 'zombie forest' in its wake, expert warns

A forester from Bancroft, Ont., says the province could be doing much more to deal with an insidious disease that's killing beech trees across Ontario.

Forester calling on province to help slow spread of beech bark disease

Beech bark disease infects the tree from the inside out, slowly killing it. (Ontario Ministry of Natural Resources)

A forester from Bancroft, Ont., says the province could be doing much more to deal with an insidious disease that's killing beech trees across Ontario. 

Svetlana Zeran called in to CBC's Ontario Today Monday to say beech bark disease is a major concern on the nearly 400,000 hectares of forest her company manages.   

"We have been dealing with beech bark disease for about a decade," Zeran said. "Now that it is here on the [Canadian] Shield, it is moving very rapidly and we are seeing the disease come in and infect the trees and they are dead within two to five years."

The disease begins when an insect bores holes in the bark, allowing a red fungus to invade the tree and slowly weaken it from the inside out.

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Infecting young trees 

Zeran said as mature trees die saplings rise in their place, but the young trees are also susceptible to the disease and crowd out other potential new growth. 

It is a self-perpetuating cycle. I call it the sort of zombie forest.- Svetlana Zeran, forester

"It will keep re-infecting those young saplings that will never reach maturity, will never produce beech nuts," she said. "It is a self-perpetuating cycle. I call it the sort of zombie forest."

Zeran said her company would like support to go into the forest and removed dead or dying trees to potentially limit the spread of the disease. She said so far, the government has not been receptive. 

"It's been a struggle just trying to get the funding to get the people to do the work," she said. "I think it should be a priority to start removing it from the forest."

No way to halt disease, ministry says

Ministry of Natural Resources and Forestry spokesperson Jolanta Kowalski said unfortunately, there really is no way to control the disease. 

"There is no insecticide or fungicide that can be applied to kill the beech scale insect or the canker fungus. Such treatments are not practical in a forest setting anyway," she said in an email. 

Kowalski said removing trees can help from a safety perspective, but it isn't a long-term solution to the problem. 

"Removing trees that are diseased is a good idea from a safety standpoint, as they tend to break and fall over in wind storms, but it will not reduce disease levels in the forest."