Beech Bark Disease contaminates our forests
While enjoying our forest walks here at Spiritwood, my husband Eric and I usually visit our several groves of American Beech trees. We love their stately form, smooth grey bark – and the telltale clawmarks left by Black Bears, who climb these trees to eat the nuts in autumn.
A few weeks ago, we noticed fuzzy white insects attached to the bark of almost all the Beech trees with a diameter of more than about 4 cm. With a sinking sensation, I realized our grove is likely infected with Beech Bark Disease (BDD).
I took photos of a few infected trees and sent them to Gatineau Park Director Catherine Verreault (whom I interviewed a few weeks ago in this column).
I contacted Ms Verreault because I know she’s an informed biologist by profession, and also because Spiritwood punches into Gatineau Park. Therefore, I wanted her to be aware this disease may be in the Park.
She confirmed that the photos prove the presence of BDD.
Gatineau Park Tree Specialist Bruno Chicoine
Mr. Chicoine called me on Monday May 9, explaining that the disease has been in the Park for ten years or so. He said the NCC has been monitoring BDD in public areas such as Lac Phillippe campground.
Unfortunately, there’s nothing that can be done to cure the trees: BDD is fatal.
What is BDD?
An alien (non-native) insect called Cryptococcus fagisuga – a type of scale – is host to a fungus (Neonectria faginata). The white fluffy insects we see on our Beech trees (see photo) are the females which coat themselves with the waxy substance to protect themselves. They drill holes in the bark of the Beeches.
The hole provides a way into the tree, and this is how the fungus gains access, infecting the tree, particularly its cambium layer.
Eventually the tree develops cankers and deformation of the trunk, and eventually dies.
Disease stimulates seed production
In the years before they die, the Beeches increase seed production. Chicoine explained, “When trees are attacked, they respond by producing far more seeds and, in the case of Beeches, Willows and Poplars, diseases also stimulate root suckers. It’s how the plants try to survive as a species.”
He noted that it’s not the insect that’s killing the trees, but the fungus. And, whereas Dutch Elm disease kills its host in a matter of weeks, BBD kills in several years.
Beech lumber compromised
I asked Chicoine whether the timber from the infected trees is still good for firewood or cabinetry. “No,” he said. “Unfortunately BDD lowers the quality of wood for sawing.”
Anecdotally, I’ve heard that the Beech wood is punky and useless even for wood stoves.
Chicoine explained that BDD can be spread if we take contaminated wood off our own properties.
There’s no known antidote. Anecdotally, a friend said she had used tea-tree oil on one of her several Beeches and noted that it was the only individual of her Beech grove which seemed to be surviving.
Chicoine was interested in this and suggested that I try it… However, when he realized our grove here at Spiritwood is about 50 members strong, with two other large groves being of approximately 200 + to 400+ trees, he said that there’s no hope of saving our Beech forest.
Along with the decline of White Ash and Spruce respectively from Emerald Ash Borer and Spruce Budworm, and the Butternut (White Walnut) trees succumbing to canker, Chicoine, Eric and I share concerns about the health of the forests not only in Gatineau Park but everywhere.
The additional worry of course, as trees die and litter the forest, is that the understory becomes less protected because of lack of shade from mature canopy trees. Accompanied with parched, dry soils and plants due to drought, I am deeply concerned about forest fires.
For more information about BDD:
bit.ly/3yyVpwS bit.ly/3l6DVjb bit.ly/39jltS0
Katharine Fletcher is a freelance writer and artist. Contact her at: firstname.lastname@example.org and view her art at facebook.com/KatharineFletcherArtist