Edmonton detects 7th case of Dutch elm disease since last summer

A streak of four months without a new case of Dutch elm disease (DED) in Edmonton has just come to an end.

The city says a tree in the Glengarry neighbourhood has tested positive for the deadly fungal disease.

It’s Edmonton’s first new case since July, and the seventh since August 2024.

“An inspection in October found the tree in declining health and triggered its prompt removal,” the City of Edmonton said in a news release. “While the tree initially tested negative, fungal collections from the tree appeared to match DED under a microscope and were submitted for additional testing.

“These results confirmed the presence of the fungus.”

Trees within 20 metres of the diseased elm were also removed, the city says, and enhanced monitoring and assessments of trees within a one-kilometre radius of the diseased tree are in place.

The tree that tested positive for Dutch elm disease in July was in the Alberta Avenue neighbourhood. The previous five infected trees were in the Killarney and Yellowhead Corridor East neighbourhoods.

The city says the existing protocol zone established around the Killarney neighbourhood will be extended to include Glengarry and adjacent neighbourhoods.

Dutch elm disease is a contagious fungal infection that poses a major risk to nearby elm trees.

“An ongoing diligent pruning program to remove the deadwood in elms is necessary to reduce the habitat of the beetles which may spread the fungus,” the city said in a news release.

There are some 90,000 elm trees in Edmonton – around 22 per cent of the city’s boulevard and open space trees.

The city says it has conducted 185,510 visual surveys and submitted 57 samples for testing this year.

Edmontonians are asked to help limit the spread of Dutch elm disease by not bringing firewood from another jurisdiction; removing bark beetle habitat; and calling 311 if you see signs of the disease.