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Michigan DNR warns oak wilt tree disease is spreading across state

BRIGHTON, Mich. – Oak wilt is a fungus and a quick tree killer which shows up between April 15 and July 15.

It first appears as a gray clump on injured bark called a "pressure pad." It also splits the bark. The disease is apparent when a tree's leaves change color months too early.

"Red oak trees go from being perfectly healthy in the spring time to being dead within two weeks time often," said Roger Mech.

Mech is a forest health specialist with the Michigan Department of Natural Resources. He said oak wilt is moving across the state of Michigan at an alarming rate -- similar to the emerald ash borer.

"It smells a lot like Juicy Fruit gum, believe it or not, and it attracts sap-feeding insects. Those insects come in. They chew on those spore-producing pads. They fly off, they look for more sap and fresh sap to feed on," said Mech.

The best way for you to prevent its spread is not to move firewood from your property, whether you have red oak or not.

"The firewood cut from infected trees forms spores and those spores can be moved very easily on firewood and when it's stacked, if it's stacked near -- probably within a mile or two of red oak -- that red oak becomes at-risk," said Mech.

Unlike the ash borer, the state of Michigan can prevent the spread of oak wilt by using cable-laying equipment and slapping a 5-foot blade on the back which cuts the root connections between trees. The trees inside the circle the blade cuts are cut down and burned.

The state of Michigan is working to save its trees in its forests but doesn't have the budget to help you with yours. There is a chemical you can inject into your trees that might save them but you need to hire an arborist to do that.

Helpful information on oak wilt in Michigan:

PDF: Oak Wilt in Michigan's Forest Resource
Info: Oak Wilt in Michigan's lower peninsula
Help: Oak wilt treatment
Michigan.gov: DNR advises caution to prevent spread of oak wilt disease