French common name: Chancre du noyer cendré
Scientific name: Sirococcus clavigignenti-juglandacearum Nair, Kostichka & Kuntz
Alternative: Ophiognomonia clavigignenti-juglandacearum (Nair, Kostichka & Kuntz) Broders & Boland (Oc-j)
Butternut canker disease affects butternut trees, and occurs when the S. clavigignenti-juglandacearum fungus enters the tree and causes cankers to form on the trunk, branches, or exposed roots. Canker development on the trunk can girdle the tree, leading to canopy dieback and eventual tree mortality.
Butternut canker disease is present throughout the natural range of the butternut tree in North America, which is especially worrisome as this tree is endangered in eastern Canada. The origin of the fungus that causes butternut canker disease is not known, though some scientists trace it back to Asia.
Photo: Taylor Scarr, OMNRF