Dutch Elm Disease

What is it?

Credit: Joseph OBrien, USDA Forest Service, Bugwood.org
Credit: Joseph OBrien, USDA Forest Service, Bugwood.org

Dutch Elm Disease (DED) is a fungal infection that clogs the elm tree’s water conducting system, causing the tree to die. The fungus is primarily spread from one elm to another by three different beetle species.

Why is it a problem?

Once an elm tree is infected with DED, the disease progresses rapidly and will kill the tree within one or two seasons. Alberta and British Columbia are the last two locations in North America that are considered DED-free. The disease is not curable, only preventable, so once it occurs in a tree, it will quickly spread and can kill a large population of elms in a relatively short time.

How to identify DED

Some common symptoms include:

  • Leaves on one or more branches suddenly wilting, drooping, or curling
  • Leaves turning brown and shrivelling but not falling
  • Discolouration which can be seen once the bark is peeled back (healthy elms have cream coloured wood but infected elms may have dark brown or red streaks)

What to do if you suspect DED

If you suspect your tree may be infected with DED, call the Stop Dutch Elm Disease hotline at 1-877-837-ELMS.

All dead elm wood should be removed and properly disposed of by burning, burying, or chipping by March 31. Please note that it is illegal to store elm as firewood.

Proper prevention

The beetles feed on healthy elm trees and breed in dead and dying elms in the winter months. In order to prevent the spread, elm trees will need to be pruned. The only time pruning of elm trees is permitted is between October 1 and March 31. This is when the beetles are not active. If elm trees are pruned between April 1 and September 30, the beetles will be drawn to the scent of the fresh cuts, potentially attracting infested beetles to infect an otherwise healthy elm tree.

Properly pruning your tree is important! A professional arborist can determine what type of pruning is necessary to maintain or improve the health of your trees.

How does the City manage public trees that are infected with DED?

The City of Spruce Grove inspects public elm trees for DED between October 1 and March 31 to see if any trees need to be removed. The general public is not permitted to damage, disturb, remove, move, cut, or prune public shrubbery or a public tree.

For more information on how to prevent DED call the Stop Dutch Elm Disease hotline at 1-877-837-ELMS.


Call Public Works at 780-962-7584 or email Public Works.