Saskatoon records single case of Dutch elm disease

A deadly infection that affects elm trees has crept back into Saskatoon.

The city revealed on Monday a single case of Dutch elm disease (DED) was found in Leif Erickson Park in the Westmount neighbourhood. The infected tree will be removed Tuesday and additional surveillance and testing will continue on elms in the immediate area.

“This discovery of Dutch elm disease demonstrates that our ongoing surveillance and screening procedures work,” said Darren Crilly, the city’s director of parks. “Our response plan has been effective in ensuring we identify diseased trees early on, limiting the spread of the disease through rapid removal.”

This is the third case of DED in Saskatoon since 2015.

The disease is transmitted by elm bark beetles and through root grafts. It blocks water movement and eventually kills the entire tree.

Entomologist Sydney Worthy said DED is a serious issue, with elms making up about 25 per cent of the city’s urban forest.

“The disease was introduced into North America in the 1930s and has since spread mainly through the transport of firewood and lumber,” Worthy said. “It has wiped out millions of elms across Canada and the United States and has been present in Saskatchewan since the 1980s.”

The most effective management strategy for DED is to not transport or store elmwood. Infected firewood is the most likely way that DED would be brought into Saskatoon.

Last year, the city issued 71 infraction notices (46 of which contained elm firewood) and removed over 13 tonnes of elmwood from private property.

The provincial pruning ban of elms runs from April 1 to Aug. 31.

DED leaves will start to wilt and turn yellow, then curl and turn brown. Residents who start to notice any of these symptoms are encouraged to call the city at 306-975-2890 or visit the city’s website.