Wisconsin DNR Forest Health Specialist Paul Cigan out of the Hayward office asked the Lake Owen Association to notify the Lake Owen community of the following information about the recent infestation of the Oak Wilt disease.  Oak wilt disease was first detected in Bayfield County in 2018, and the number of known cases in the Cable Lakes area has increased significantly in 2019.  Oak wilt is the most deadly disease facing oaks in Wisconsin and kills red oaks within 1 month after infection.  Death of oaks can create hazardous trees, reduce property values and aesthetics, and may reduce wildlife habitat and water quality.  The disease can easily move from tree to tree through grafted roots, making control costly and difficult.  Prevention is the best approach.

In the summer of 2019 there have been confirmed cases of the disease on properties near Lake Owen; it is highly likely there are more cases on other properties.

Several simple prevention steps:

  • Don’t prune, wound, or cut down oak trees April through July every year.  If oak are cut, injured by storms or other sources, apply a pruning paint (latex paint fine) to the stump or wound surface ASAP, but not more than 48 hours later.
  • Keep firewood local and know if the wood may be diseased.  Do not transport firewood long distances to your property.
  • Become familiar with oak wilt symptoms and call your local DNR or county forestry office for help with diagnosis.

Know the symptoms:

  • Rapid leaf drop late June – September.  Generally starts at the top and outside of the crown and moved down and inward.
  • Fallen leaves with a brown or bronze colored edge and green center or base.
  • Groups of dead oaks indicating root graft spread of the disease.

Together we can ensure our beautiful oaks and surrounding forests stay healthy and vigorous for decades to come.

If you have specific questions or want more information on oak wilt diagnosis, prevention, and control, you can contact Paul Cigan, the Wisconsin DNR forest health specialist for the n.w. region, in person or mail at the Wisconsin DNR Office at 10220 N. State Hwy 27 South, Hayward, WI 54843, or by phone: 715-416-4920 or his email: Paul.Cigan@wisconsin.gov