Invasive species confirmed in City of Hamilton hemlock trees

HAMILTON, ON – The Canadian Food Inspection Agency (CFIA) confirmed the presence of hemlock woolly adelgid (HWA) in hemlock trees on City of Hamilton and Royal Botanical Gardens (RBG) property, located in the forested areas surrounding Churchill Park.

Due to the confirmation of the invasive pest, the CFIA has issued a Notice of Prohibition of Movement to both the Royal Botanical Gardens and the City of Hamilton to restrict the movement of hemlock material (firewood, branches, mulch) for this area.

The City’s records indicate that hemlocks comprise a small portion of the forest inventory, with only 321 trees on streets, parks and cemeteries. This makes the threat of HWA low for these areas. The impact of HWA to hemlocks in Hamilton’s publicly owned woodlots is harder to quantify because the woodlot inventory is incomplete, and the impact to privately owned woodlots is not known as the City does not have that data.

HWA can be identified by its egg sacs, which can be found at the base of needles and look like cotton or snow clumps. The City is asking residents who have hemlock trees on their private property to inspect their own trees for the pest. If residents suspect HWA to be present on their hemlock trees or on a City tree, they are asked to call their local CFIA Office at 905-572-2201 to have an official identification completed. Residents should not attempt to remove the pest themselves.

For further information on the pest and how to identify HWA on hemlock trees, visit: www.hamilton.ca/invasivespecies.

Quick Facts:

• Hemlock Woolly Adelgid - Adelges Tsugae (HWA) is a destructive aphid-like pest of eastern hemlock, an ecologically significant tree species in eastern Canada.
• It feeds on the base of the needles, causing needle drop and tree mortality in as few as four years.
• HWA poses no threat to humans, animals, bees or other insects.