Dutch Elm Disease

Dutch Elm Disease (DED) is caused by a fungus that clogs an elm tree's water conducting system, causing the tree to die.  The fungus is primarily spread from one elm tree to another by beetles.

How to spot DED

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.

What can you do?

  • Be aware of the Alberta elm pruning ban between April 1and September 30.
  • Keep your elm trees healthy, and vigorous.
  • Water elms well from April to mid August.
  • Only between October 1 to March 31, remove dead branches and trees as they can provide beetle habitat.
  • Dispose of all elm wood immediately by burning, burying or chipping.
  • Report all suspect trees to the DED Hotline at 1-877-837-ELMS. A confirmed DED tree must be removed immediately to prevent further spread.

What you shouldn’t do

  • Do not transport or store elm firewood at any time!
  • Do not transport elm firewood into Alberta!
  • Do not prune elms between April 1 to September 30.

For detailed information about Dutch Elm Disease, visit the Government of Alberta website External