The annual elm-pruning ban in Alberta has been lifted until March 31.
“With the annual ban now lifted, it’s time to start taking the dead wood out of your elm trees,” said Janet Feddes-Calpas, executive director of the Society to Prevent Dutch Elm Disease. “To help eliminate elm bark beetle habitat, elm sanitation is essential to an integrated Dutch elm disease (DED) prevention program to keep Alberta DED free.”
The only time it is legal to prune elms in Alberta is between October 1 and March 31.
“This is when the elm bark beetles, responsible for spreading the deadly DED fungus, are not active,” said Feddes-Calpas. “Elm bark beetles feed on healthy elms and breed and overwinter in dead and dying elm trees. If elm trees are pruned between April 1 and Sept. 30, beetles will be drawn to the scent of the fresh pruning cuts, potentially infecting an otherwise healthy elm.”
Her organization recommends hiring a professional arborist, such as an ISA certified arborist, who can determine what type of pruning is necessary. Improper pruning, topping or removing an excessive amount of live wood is not recommended, as this weakens the tree’s structure and shortens its lifespan.
All pruned elm wood must be properly disposed of — by burning, burying or chipping — by March 31. It is illegal to store elm firewood because it can habour elm bark beetles.
While Alberta is still free of DED, its borders are being pressed from two sides, Saskatchewan and Montana, both of which are battling the disease.
“Once an elm is infected with DED there is no cure and it must be removed and destroyed immediately,” said Feddes-Calpas.