Pockets of oak wilt to be treated at Rib Mountain State Park

Discussion in 'Outdoor News' started by Wisconsin DNR News, Sep 27, 2016.

  1. By Central Office September 27, 2016

    Contact(s): Michael Hillstrom, DNR Forest Health Specialist,715-459-1371 or [email protected]

    WAUSAU, Wis. - Visitors to Rib Mountain State Park may notice some activity along the main entrance road in the next week as Department of Natural Resources staff continue to address an outbreak of oak wilt in the park.

    Oak wilt is a fungal disease that can rapidly kill infected trees. The disease can affect all oak species but is most severe in the red oak group. The disease has been present in Marathon County for many years and was first confirmed in the park in 2014.

    "Oak wilt spreads in two ways -- by sap beetles feeding on fungal pads produced on infected trees and also through connected oak roots," said Mike Hillstrom, DNR forest health specialist. "We previously removed infected trees, but we also need to stop the disease from spreading underground through roots connected to nearby oaks."

    In coming weeks, forestry staff will use chainsaws to cut 1-2 inches into the base of oaks surrounding the infected trees and spray them with an herbicide to kill the roots and prevent the disease from further spreading across the park. All treated trees will be removed by a professional logger or arborist this winter.

    The fungus was likely spread to the trees by beetles after storm damage occurred a few years ago during the high risk period for oak wilt, which runs from April 15 to July 15 in Marathon County. Landowners should not prune or damage oak trees during this time period and should cover any wounds quickly with tree paint if they do occur during that time period.

    People can learn more about oak wilt by searching the DNR website, dnr.wi.gov, for keywords "oak wilt."

    Last Revised: Tuesday, September 27, 2016