Delay pruning of oaks to prevent oak wilt

Avoid potential risk of infection by waiting until November to prune oaks.

Oak wilt, caused by fungal pathogen Ceratocystis fagacearum, is present in Michigan. One of the most effective ways to prevent infection of healthy trees is proper timing of any oak pruning. Pruning creates wounds that are attractive to beetles, some of which vector the fungal pathogen. Infection can subsequently occur through these wounds.

Ideally, oak pruning is delayed until November, when the risk of infection has passed. If circumstances do not allow this, pruning wounds should be painted with a wound sealant or latex paint.