City's Dutch Elm Disease Program
The City of Regina follows an integrated Dutch Elm Disease (DED) management program to prevent the disease from spreading throughout the city and limit the number of local trees lost to this disease.
Between 1981 and 2017, we have lost only 103 trees to DED. No area of the city has escaped; therefore all elm trees are at risk.
This DED Brochure teaches you how to fight Dutch elm disease. Use the City's online Contact Us form or call 306-777-7000 if you suspect a private or City-owned tree in your neighbourhood has the disease.
Step 1 – Monitoring and Surveillance
City workers systematically inspect all City-owned and private trees once every two weeks for wilting or yellow leaves on one or more branches on a tree. If a tree looks suspect, staff take samples and submit them for laboratory culturing to see if the tree has the DED fungus.
Step 2 - Elm Bark Beetle Monitoring
Elm Bark Beetles can carry the dutch elm disease fungus as they move from tree to tree. As part of a management strategy, it’s important to be aware of the risk they pose to the urban forest. So we monitor beetle numbers throughout the city. To accomplish this we use pheromone traps.
- We have 86 traps set up to attract and apture elm bark beetles
- There are three species that we trap in Regina:
- European elm bark beetle (Scolytus multistriatus)
- native elm bark beetle ( Hylurgopinus rufipes)
- banded elm bark beetle (Scolytus schevirewi)
The US Forest Service provides great photos and explanations of beetles.
Step 3 - Pruning and Sanitation
The City immediately cuts down and buries all infected wood from elm trees at the City of Regina landfill. Under this program, the City also prunes deadwood from City elm trees and removes hazardous trees after the pruning ban is lifted. Provincial legislation imposes a pruning ban between April 1 and August 31 every year.
By taking away the dead wood in the tree we also take away safe harbourage areas for the elm bark beetle to feed and reproduce.
Dutch elm disease can spread easily because trees are often planted close together. Under the ground and through tree roots is one way the disease begins to spread. The roots of trees closely planted together begin to graft and act as one giant root system.
To stop the Dutch elm disease fungusfrom taking advantage of this “back door” approach into the neighbour’s tree, we inject neighbouring trees with a fungicide called Eertavas. This is a new innovative approach we are using to control the disease in more environmentally friendly way.
In the past, we would spray the bottom of elm trees with chlorpyrifos, an insecticide to control the beetles as carriers of the disease. Now we focus more directly on the disease itself by targeting the fungus on the inside of the tree and its root system, not on the carrier insect.
Step 4 - Infill Planting
Each spring and fall, City crews plant other tree species in locations where elm trees have been removed due to age, damage, or disease. We try to increase the biodiversity of the urban forest. It does not mean we won’t plant elm. It means we will look at increasing the biodiversity of the whole urban forest. Did you know we have more than 13 different Genera of tree species in the urban forest? Elm is only one of those.
Step 5 - Firewood Inspections and Collections
Elm firewood is ideal for elm bark beetles to lay eggs. Provincial DED regulations state you cannot "store, use, market or transport any elm tree for use as fuel wood or any other purpose."
If the City finds elm wood on your property, workers will leave a letter advising you to dispose of the firewood. If you don’t remove the firewood, the City will collect it and destroy it.
The City’s Pest Control Team will help you to identify elm firewood or investigate reports of suspected elm firewood on private property.
Step 6 - Public Awareness
The City educates residents about DED through media interviews, radio, television and print advertising as well as brochures, fridge magnets, and tree ribbons. The City also placed signage at all City entrances advising motorists to the danger of transporting elm firewood.
Step 7 - Research
Research allows Pest Control to keep in touch with the latest developments and assists in directing efforts towards issues relating to our climate/zone.
The fungicide Eertavas was a result of one of such research trials. When the product was in its field trial stage, the City participated in those trials. Now we’ve incorporated those results into a long-term program going forward.