Winnipeg elm tree loss overshoots target: report

City of Winnipeg crews work to cut down an elm tree on March 23, 2021. (Mason DePatie/CTV News Winnipeg)

The City of Winnipeg marked 6,616 American elm trees for removal last year due to Dutch elm disease, resulting in a 3.4 per cent loss rate — extending beyond the annual average target.

According to an administrative report on the status of Dutch elm disease management in Winnipeg, the city has approximately 194,390 American elms, described as “the largest American elm population of any North American city.”

The annual average target for the city’s loss rate of American elms is listed at two per cent.

Dutch elm disease is a fungal infection that blocks the tree’s water-conducting tissues, spread mainly by native elm bark beetles, according to the city’s website.

Altogether in 2024, just over 7,000 elms were removed under the Dutch elm disease management program, which includes trees that were tagged during previous years.

The report says that approximately $172 million has been directed to management since the disease was detected in the city 50 years ago to “slow the spread” and to preserve the elm canopy.

A city spokesperson said that about 300,000 elms have since been removed.

The widespread planting of American elms, “once a characteristic of many Winnipeg neighbourhoods,” is listed as a contributing factor in the spread of the disease.

City would lose ‘almost all’ elms by 2045 without management: report

According to the report, the city would lose “almost all” of its American elms in the next 20 years if Dutch elm disease management were to stop today. Under this scenario, the total removal cost would be approximately $200 million, without adjusting for inflation.

The city said though the average annual loss rate in Winnipeg has “varied considerably over time,” the loss rate over the past five years has been approximately 2.2 per cent in parks and on boulevards.

The five-year average annual loss rate for elms on all property types is 3.6 per cent.

The city’s Dutch elm disease management program includes removal of diseased and declining trees, firewood monitoring and disposal, elm bark beetle control, reforestation and public education.

The report said, “The City of Winnipeg program has been the most successful (Dutch elm disease) management program in North America.”

Nearly 6,500 trees were planted last year on boulevards and in parks as part of reforestation efforts, according to the report.

Elm trees currently represent 22 per cent of the city’s public tree inventory.