Winnipeg starts initiative to save elm trees
City plans to spray trees to control beetles that cause Dutch elm disease
A small beetle is attacking Winnipeg's elm trees and the city is going to fight back.
The beetles carry a fungus that leads to Dutch elm disease, which kills about 6,000 trees in the city every year.
Weather permitting, crews plan to start spraying trees to get rid of the beetles in parts of the capital on Monday, the city said in a press release.
Winnipeg's elm trees are at a higher risk of succumbing to Dutch elm disease now because of low levels of precipitation during the last few years, the city said in the release.
Dutch elm disease was first detected in Winnipeg in 1975, according to the city's website. The infection blocks a tree's water-conducting tissue and can kill it within weeks of infection.
Winnipeg is at risk of losing its urban forest because of challenges presented by Dutch elm disease and other threats to the tree canopy, according to a report earlier this year. Of Winnipeg's estimated 3,075,000 trees, elms made up about 25 per cent last year.
While the city's canopy has been relatively stable over the years, the rate at which elm trees are being removed in Winnipeg now surpasses that rate at which new ones are planted, the report said.
Tree removal
Winnipeg's urban forestry branch inspects all the city's elm trees for the disease every year from mid-June to mid-September. If a tree is marked for removal, it will be cut down within a year, according to the city's website.
The initial spraying will start with tree trunks in these zones:
- Insect management area 19 (Maple Grove Park, Normand Park, River Park South, St. Vital Centre, Vista).
- Insect management area 20 (St. Vital Perimeter South).
- Insect management area 21 (La Barriere, Parc La Salle, Perrault, Richmond Lakes, St. Norbert, Trappistes, Turnbull Drive).
- Insect management area 31 (Central River Heights, J.B. Mitchell, Mathers, Sir John Franklin, South River Heights).
The city said it will make public service announcements every Friday to let people know which other areas will be treated the following weeks.
A map of those zones is available on the city's website.
Treatment will happen between 5 a.m. and 5 p.m. using Pyrate 480 EC (chlorpyrifos), which will be sprayed directly on the lower 50 centimetres of the tree trunk.
The chemical product is approved for use in Canada but is not recommended when temperatures are above 15 C, the city said.