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Help protect Alberta’s beautiful elm trees

June 22 to 28 is Dutch Elm Disease Public Awareness Week.

See event listings and more articles in this edition of Agri-News: June 20, 2022 issue

“STOP a killer from entering Alberta.”

“The Society to Prevent Dutch Elm Disease (STOPDED) is asking for your assistance to save our beautiful elm trees from the deadly Dutch elm disease (DED),” says Janet Feddes-Calpas, executive director of STOPDED. “Alberta has been fortunate to remain DED free but is constantly aware of the threat of the disease pressing the Saskatchewan and Montana borders.”

One of the largest spreaders of DED are the elm bark beetles (EBB) that can carry DED on elm firewood. Beetles can hitch a ride on infected elmwood and be carried by unsuspecting campers and homeowners.

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 one of the 3 EBBs: the smaller European elm bark beetle, the banded elm bark beetle, or the native elm bark beetle. The beetles are attracted to weak and dying trees, which 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, thus transporting the fungus on their bodies from one tree to the next.

Under the Alberta Agricultural Pests Act (APA) Pest and Nuisance Control Regulation (PNCR) the DED pathogens and the EBBs are named declared pests. All municipalities, counties and MDs in the province of Alberta have the responsibility and authority to prevent and control DED under the APA.

For those municipalities that do not have a DED bylaw in place, the APA provides a means for enforcement. Several sections of the APA and the Regulation can be applied. It is an offence not to take ‘active measures’ and not to follow an Inspector’s Notice which can be issued by an agricultural fieldman, community peace officer, a municipal officer that has dual municipal and provincial appointments, or an APA pest inspector appointed by the municipality. They all have the powers and responsibilities outlined under the APA Section 17 to enforce the Alberta DED Prevention/Control Measures to the landowner.

“Using traps and lures, monitoring for the EBB is done annually throughout Alberta by STOPDED. Only the smaller European and the banded beetles have been found on traps throughout the province in low numbers since 1996. In recent years, higher numbers of the banded EBB have been found in the City of Medicine Hat and now are being found in more municipalities in southern Alberta,” says Feddes-Calpas.

There have been 2 isolated cases of DED in the province, one in the Town of Wainwright in 1998, and the last, in the City of Lethbridge in 2020. The trees were immediately removed and buried. Elm trees in both municipalities were immediately surveyed for signs of disease in elm trees and elm firewood near the detection sites.

What can you do?

Feddes-Calpas says there are a number of things Albertans can do to help stop the spread of DED.

  • Know the DED symptoms. Leaves on a DED-infected elm will wilt or droop, curl and become brown. This appears in mid-June to 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.
  • If you feel an elm has DED symptoms, please phone the STOPDED hotline at 1-877-837-ELMS. All suspect elms must have a sample taken from the infected part of the tree and tested by the Alberta government’s lab. Lab costs are covered by the Alberta government. In order to prevent an uncontrolled outbreak, the DED positive elm must be removed and destroyed immediately.
  • Be aware of the provincial 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 your elm trees healthy.
  • 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.
  • Remove dead elm branches as they can provide beetle habitat only between October 1 and March 31.
  • Dispose of all elm wood immediately by burning, burying or chipping.
  • Report all suspect trees to the DED Hotline at 1-877-837-ELMS.

What you should NOT do

  • Do not transport or store elm firewood at any time.
  • Do not transport elm firewood into Alberta. Firewood is confiscated at all the Alberta-Montana border crossings.
  • Do not prune elms between April 1 to September 30.

To report a DED suspect elm tree or for more information, call the STOPDED hotline at 1-877-837-ELMS (3567) or check out the website at

“We must stay vigilant to keep our elms healthy. DED can be prevented,” says Feddes-Calpas.

For more information, see:

Society to Prevent Dutch Elm Disease


For more information, connect with Janet Feddes-Calpas.

Phone: 1-877-837-ELMS (3567)
Email: [email protected]

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