This spring, we’re on the lookout for two priority forest pests; hemlock woolly adelgid and oak wilt! Hemlock woolly adelgid (HWA) is native to Asia, and was first detected in eastern North America in the 1950’s. This invader attacks native hemlock species, which are commonly found in Ontario forests and urban spaces.
Look for white, cotton-like or woolly masses forming on the base of hemlock needles.
To learn more about the hemlock woolly adelgid, visit the species profile.
Oak wilt is a vascular disease of oak trees caused by the fungus Bretziella fagacearum. The fungus grows on the outer sapwood of oak trees restricting the flow of water and nutrients through the tree. Oak wilt has spread throughout the Eastern United States. In 2016, it was confirmed on Belle Isle in Michigan, in the middle of the Detroit River, 579 metres from the shores of Windsor, Ontario. Visit the species profile to learn more about oak wilt.
If you see signs and symptoms of either of these forest pests in Ontario, please report the sighting to the CFIA or EDDMapS Ontario.