Dutch Elm Disease Public Awareness Week June 22-28

STOP a killer from entering Alberta
Dutch Elm Disease Public Awareness Week June 22-28

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). 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 three 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 land owner. The measures can be found at https://open.alberta.ca/publications/dutch-elm-disease-prevention-control-measures-responsibilities-authority-apa.

Using traps and lures, monitoring for the EBB is done annually throughout Alberta by STOPDED. Only the smaller European and the banded 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. There have been two isolated cases of DED in the province, one in 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?

• 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 Province of Alberta’s Agriculture, Forestry and Rural Economic Development’s (AFRED) lab. Lab costs are covered by the AFRED. 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 31st.
•  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 or check out the web site at www.stopded.org.

We must stay vigilant to keep our elms healthy. DED can be prevented.

Janet Feddes-Calpas
STOPDED Executive Director