What is the laurel wilt disease cycle?
Much is still unknown and unstudied about the laurel wilt disease cycle. Female redbay ambrosia beetles carry spores of the laurel wilt fungus at the base of their mouthparts. Trees become inoculated with the fungus when these beetles bore into the xylem (sapwood). There is evidence to suggest that initial inoculation of trees may happen in the crown, but early attacks may not be limited to this location. The fungus gradually colonizes sapwood throughout the stem, causing the tree to wilt and die in a matter of weeks or a few months. As the tree wilts, it becomes suitable breeding material for the ambrosia beetles, which colonize the stem, reproduce in the sapwood, and cultivate the fungus on gallery walls as food. Emerging female redbay ambrosia beetles fly and initiate new infections on healthy trees or colonize dead/diseased trees. See also the Disease Cycle and Pathogen pages.
