Provincial regulations prohibit pruning elm trees from April 1 to August 31 each year to reduce the risk of spreading Dutch elm disease (DED). The elm bark beetles that can carry DED are most active during this time of year, and fresh cuts from pruning can attract the insects to healthy elm trees.
Regular pruning, outside the ban period, is great for keeping elm trees healthier and less vulnerable to all types of diseases, including DED. Taking away the dead branches makes trees less attractive to elm bark beetles. The early fall weather can be ideal for tree maintenance and, with leaves still on the trees, homeowners have an easier time seeing and removing dead or unhealthy branches.
It’s important to prune properly, whether you hire someone or do it yourself. Pruning incorrectly can actually spread DED and other tree diseases. Under provincial regulations, commercial pruners of elms must complete a recognized training program or be supervised by someone who has.
It is illegal to transport or store elm firewood because the wood attracts the beetles that spread DED. Dispose of elm wood promptly by burning or burying it in a location approved by the local municipality. To find out more about proper elm disposal in your area, check with your local municipal authority.
For more information, or if you suspect an elm tree may have DED, call the Ministry of Environment’s general inquiry line at 1-800-567-4224.