Islanders are being advised to take preventive measures against the spread of a tree fungus now discovered in three spots across P.E.I. Butternut canker, a rapidly spreading disease that targets butternut trees, although not native to the Island, are extensively planted throughout the province.
Clay Cutting, a technician with the P.E.I. Invasive Species Council, described butternut canker as a fatal condition once a tree becomes infected, with no known method to halt its spread. The disease leads to the tree’s demise as multiple cankers collaborate to encircle and kill the host tree.
The council is cognizant of the severe impact of the fungus on butternut tree populations, drawing from the devastation witnessed in other provinces. In Ontario, over 80% of butternut trees have succumbed to butternut canker, with an infection rate exceeding 99%.
Initial observations of the fungus were made in Stratford’s Robert Cotton Park in 2024, followed by surveys in Charlottetown and Stratford confirming a majority of butternut trees exhibiting signs of infection. The Canadian Forest Service scientists authenticated the disease’s presence in July.
Symptoms of butternut canker include sunken cankers on trunks and branches exuding a black substance, with variations in appearance depending on the infection duration and time of year. The fungus spreads primarily through rainfall, dispersing fungal spores across the tree canopy.
While rainwater serves as the confirmed mode of transmission, other potential spread avenues such as handling firewood or contact with insects and birds are not ruled out. Control methods for affected populations are non-existent, and regulatory constraints may limit the removal of butternut trees due to their endangered status under P.E.I.’s Wildlife Conservation Act.
Islanders can aid in preserving tolerant trees by pruning infected branches and removing cankers to reduce fungal presence and potentially prolong the trees’ lifespan.
