Dutch Elm Disease
Saskatoon recently confirmed its third case of Dutch elm disease (DED) since 2015. As part of the City's DED Response Plan, the infected tree was immediately removed and disposed of at the City Landfill. Surveillance and testing of symptomatic elm trees continues throughout the city.
Saskatoon’s DED Response Plan requires:
- Immediate removal of all positive trees
- Disposal of infected trees at the City landfill
- Sampling of adjacent trees
- Surveillance and testing of private and public trees in the surrounding area with an intensive search for elm material and other sources of infection.
DED is a vascular disease caused by two closely related species of fungi, both of which are transmitted by elm bark beetles and tree to tree through root grafts. It blocks water movement and eventually leads to death of the entire tree. It only impacts elm trees and no elm species is totally resistant.
A tree can be infected:
- By elm bark beetles that transmit the disease
- Through root grafts between trees
- By pruning tools
American elm trees with DED may start showing symptoms as early as June. Typically, the 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 complete the online form below or call Urban Biological Services at 306-975-2890.
The most effective management strategy for DED is to not transport or store elm wood. It is imperative that elm firewood not be used at any time. It is illegal and threatens the elms that make up 25% of our urban forest.
Residents can help prevent DED by:
- Not pruning elms during the provincial pruning ban (April 1 to August 31)
- Not storing or transporting any elm firewood – Provincial regulations prohibit the storing or transporting of elm firewood
- Disposing elm wood at the City Landfill
For more information on DED: