Oak Wilt

oak wilt

Oak Wilt Disease

Oak wilt disease affects oak trees is incredibly fast moving on oaks in the red oak group (those with pointed leaf tips). After your tree is first infected, it could die within 3-5 weeks if left untreated. The fungus can be carried from tree to tree from sap-feeding beetles. When these beetles carry fungal spores to fresh wounds of an oak tree, the tree will become infected. Oak wilt can also be transferred underground through root grafts to infect other nearby oak trees. Following the initial infection, the fungus grows through the oak’s water transport system, causing it to wilt and quickly die. Oak wilt treatment is possible but must be caught early or by using prevention techniques.

How to Identify Oak Wilt Disease

Early Signs

  • Dull green/bronze leaves
  • Leaves will wilt and drop from the upper canopy most commonly during July and August

Late Signs

  • Leaves wilting and dropping from the lower The transition from upper to lower canopy happens rapidly
  • Fallen leaves are still partially green, unlike your typical fallen leaves in autumn

Oak Wilt Disease Prevention

For Homeowners

  • Learn about Oak Wilt Disease in your area
  • Watch for spore-carrying beetles
  • Careful to not injure/trim Oak trees from April to July as that is the most common time of infection from the spore-carrying beetles

Oak Wilt Disease Prevention

For Professionals

  • Wachtel Tree Science will electively prune Oak trees during the dormant season over winter to avoid pruning during the oak wilt infectious time frame from April to July.
  • Provide regular tree health checks to your property.

Oak Wilt Treatment

Fungicides can be used if caught early on or as a preventive measure

Severing the root systems between oak trees can stop the progression underground from tree to tree

If a nearby tree has died from Oak Wilt Disease, removing the wood from the area by burning or burying it can help prevent spreading the disease.

Oak Wilt Disease FAQ

Can a tree recover from oak wilt?

Treatment options are available, but because oak wilt is fast moving, remedies must be acted upon quickly in order to save the oak trees.

When is it okay to prune Oak trees in Wisconsin?

Typically, the best time to prune any tree in Wisconsin is during the dormant season (when the leaves are off). Specifically, you should not trim Oaks from April to July to prevent the spread of Oak Wilt. Your Wachtel Tree Science Certified Arborist can help to define the best time to prune your Oaks.