how oak wilt spreads

Fungal mat of spores on Red Oak

When Red Oaks are infected, spores are produced under the bark. Insects are attracted to these elliptical shaped, sweet smelling, black mats. These sap feeding beetles become covered in spores and then inadvertently carry them to wounds on uninfected trees. If the trees happen to be Live Oak or Red Oaks then a new infection occurs.

Once a tree is infected, the fungus can move from tree to tree of the same species by underground root connections. Root connections can form two times the distance from the trunk to the outermost limb often bridging gaps of 150’ on large trees. Oak Wilt spreads on average 75’ a year through these connections.