While we might think of them as self-sufficient, big and strong, the mighty oak tree has become a major target for the killer disease known as “oak wilt”. For some time now this disease has been slowly moving across our state by way of an insect called “sap beetles”. It can also be root grafted from tree to tree. We are now finding oak wilt disease killing oak trees across the Twin Cities metro area. Sanitized pruning during cooler weather is the number one prevention approach to keeping your oak tree from being the killer’s next victim. Pruning of oak trees at any other time should only be performed as a result of limb damage from storms or where trees present an immediate hazardous potential to life or structures. Oak wilt disease is not the only oak tree killer theses days. Our ongoing scouting, continues to find the dreadful twolined chestnut borer and the red oak borer attacking and killing oak trees. If left untreated these borers will result in continual tree decline and at some point it will be too late for a treatment plan to work. What to do? Prune your oaks this fall and winter an make sure your tree is inspected by one of our professionals. We can address pest threats such as borers with the appropriate timely treatments. If your tree has leaves that look yellowish in color or they appear burnt looking around the margins then you tree is potentially showing signs that it’s sick. Maybe a borer, perhaps oak wilt or even a nutrient issue but you can be assured it’s sick and asking for help. Be proactive not reactive. Call Ostvig Tree to schedule an inspection.