(WFRV) – Even though the disease is widespread in southern Wisconsin, officials say it is spreading farther north each year and want residents to prevent oak wilt from spreading.

According to the Wisconsin Department of Natural Resources (DNR), April brings the oak wilt disease across the state. As spring nears, people start to head outside and start seasonal yard maintenance.

Officials ask people to avoid wounding oak trees from April through October 1. The disease spreads by sap-feeding beetles that carry fungal spores from infected oaks to fresh wounds on healthy oaks.

The disease can also travel underground from infected trees to nearby healthy ones through interconnected root systems.

“Sap-feeding beetles, like most insects, have an incredible sense of smell, which draws them to open wound surfaces to feed on sugary sap in as little as 15 minutes after a tree is wounded,” said Paul Cigan, DNR Forest Health Specialist.

The DNR says they do not harvest or damage oak trees on state lands during the high-risk period unless very specific exceptions are met. They ask forest landowners with oak trees to do the same.

Oak wilt is reportedly in most Wisconsin counties except:

  • Ashland
  • Iron
  • Taylor
  • Door
  • Kewaunee
  • Calumet
  • Manitowoc

Another tip the DNR provided was to keep firewood local or buy Wisconsin-certified firewood. More information about oak wilt can be found on the DNR’s website.