For the first time in five years, Dutch elm disease (DED) has been found in Saskatoon’s urban forest.
The city said Tuesday an elm sample sent to the provincial lab from a tree in Montgomery Place has tested positive for DED.
Read more: No more Dutch elm disease found in Saskatoon
“Dutch elm disease is a serious disease of the American elm,” said entomologist Jeff Boone.
“The disease was introduced into North America in the 1930s, and has wiped out millions of elms across Canada and the United States. Dutch elm disease has been present in Saskatchewan since the 1980s and Saskatoon has not had a tree test positive for the disease since summer of 2015.”
Darren Crilly, the city’s director of parks, said their “screening procedures and inspection program works.”
“We have had success in the past with our response plan and are now taking the same aggressive action to stop it from spreading to other neighbourhoods.”
Crews will remove the tree on Wednesday.
Inspectors will then sweep Montgomery, Fairhaven, Meadowgreen and the South Industrial area to search for stored firewood and pinpoint a source of the latest infection.
DED was first found in the city’s urban forest in July 2015 in the Queen Elizabeth neighbourhood.
The city responded aggressively at the time, removing the tree and checking nine others within a one kilometre radius.
Crews also identified and cleaned up 12 elm wood storage infractions around the infected tree site.
DED has been present in Saskatchewan since the 1980s.
Fresh cuts on elm trees can attract the elm bark beetle, who can then spread DED to the trees.
DED is caused by a fungus that clogs the American elm tree’s water-conducting system, which can cause it to die within one or two seasons.
An elm tree in Regina was removed in 2019 due to DED and the city has had to remove over 94 trees since the disease was first detected in 1981.
There are ways to prevent Dutch elm disease:
- not pruning elm trees during the provincial pruning ban that runs from April 1 to Aug. 31;
- not storing or transporting any elm firewood, which is prohibited by provincial regulations; and
- disposing of all elm wood at the city landfill.
Infected trees can start showing symptoms as early as June. Leaves typically start to wilt and turn yellow, then curl and turn brown. Anyone noticing these symptoms should contact urban biological services at 306-975-2890.