Oak Wilt

Ceratocystis fagacearum

Oak Wilt is a vascular disease of oak trees, caused by the fungus Ceratocystis fagacearum. Oak Wilt is not yet present in Ontario, but it occurs in 23 US states including Michigan. The fungus restricts the flow of water and nutrients through the tree, causing the characteristic wilting and bronzing of the leaves. While some species of oak are less susceptible than others, the disease is able to kill some trees within a single season.