Dutch Elm disease awareness week in Alberta

The Society to Prevent Dutch Elm Disease (STOPDED) is asking for the general public’s assistance to save the nation’s beautiful elm trees from the deadly Dutch elm disease (DED).

For the News

The Society to Prevent Dutch Elm Disease (STOPDED) is asking for the general public’s assistance to save the nation’s beautiful elm trees from the deadly Dutch elm disease (DED).

“Alberta has been fortunate to remain DED free, but is constantly aware of the threat of the disease pressing the Saskatchewan and Montana borders,” says Janet Feddes-Calpas, provincial DED coordinator. “The danger of an uncontrolled outbreak of the disease still exists.”

DED is caused by a fungus that clogs the elm tree’s water conducting system, causing the tree to die. The fungus is primarily spread from one elm tree to another by two species of beetles, the smaller European and the native elm bark beetle. The beetles are attracted to weak and dying trees that serve as breeding sites for the beetles. Once the beetles have pupated and turned into adults, they leave the brood gallery and fly to healthy elms to feed, transporting the fungus on their bodies from one tree to the next. Monitoring for the beetles is done annually throughout the province.

“Leaves on a DED-infected elm will wilt or droop, curl and become brown,” says Feddes-Calpas. “These signs appear between mid-June and mid-July. Leaves on trees infected later in the season usually turn yellow and drop prematurely. Leaf symptoms are accompanied by brown staining under the bark. All suspicious elms must be tested in a lab.”

Elms are a treasure that Canadians cannot afford to lose. During DED Awareness Week, June 24 to June 30, please take a moment and find out how to help.

What individuals can do:

Be aware of the yearly Alberta elm pruning ban between April 1 and September 30. The beetles are most active at this time and can be attracted to the scent of fresh tree cuts, possibly infecting a healthy elm. Keep elm trees healthy and vigorous. Water elms well from April to mid-August to allow the tree to harden off for the winter. Watering should be stopped mid-August followed by a good soaking or two before freeze-up.

Prune elms only between Oct. 1 to March 31 to remove dead branches and trees as they can provide beetle habitat. Dispose of all elm wood immediately by burning, burying or chipping. Report all symptom trees to the DED Hotline toll-free by dialing 310-0000 and ask for 403-782-8613. A confirmed DED tree must be removed immediately to prevent further spread.

What individuals should not do: Do not transport or store elm firewood at any time. DED and the beetles are declared pests under the Alberta Agricultural Pests Act making it illegal. Do not transport elm firewood into Alberta. Firewood is confiscated at all the Alberta-Montana border crossings. Do not prune elms between April 1 and Sept. 30.