Butternut Canker - Tree Canada

the Butternut tree occurs in southern Ontario, southern Quebec, and New Brunswick
the canker was first documented in the US in 1967 but it may have arrived there before 1940
the disease reached Canada in 1990
the disease has been documented across the entire range of Butternut in Canada

a fungus disease that infects and kills Butternut trees (Juglans cinerea)
the disease enters a wound and kills inner bark on branches generally in the lower canopy
gradually, the fungus kills the upper canopy and spreads down the tree to attack trunk tissue
when the fungus has girdled the trunk, the tree dies
the disease is probably from outside North America
the fungus kills mature trees as well as saplings and seedlings
on branches, the cankers appear as white patches with a black centre
on the trunk, the fungus causes deep grooves and gashes in the bark that often ooze a black jelly-like material containing the spores of the fungus
the spores may be spread by rain and insects

the Butternut tree is an important forest species that provides valuable wood for furniture and nut crops that are used by wildlife and were important to early settlers
no tree strains are known to have resistance to the disease
in the southern US, over 75% of Butternut trees have been killed by the canker
when the trunk is killed, Butternut will not resprout from the base
Butternut is now considered Endangered in Canada due to the impact and potential impact of the disease

there is no known cure for trees infected with the canker
studies are underway across the range of Butternut to locate disease-resistant trees

Tree Killers: Butternut Canker