COLGATE, Wis. — As trees change colors during the Fall, a Milwaukee area arborist is encouraging the public to be on the lookout for zombie trees.

These are trees that look alive but are actually nearing the end of their life.


What You Need To Know

  • Zombie trees look alive but are actually nearing the end of their life

  • Arborist Adam Passo said there are several signs to detects including if trees make a hollow sound, if fungus is starting to grow out of them and if it has lost its tip branches

  • These trees are more likely to fall when pushed by strong winds

  • Wood rods can be used to extend the life of a tree but removal or replacement are also options

When checking on the condition of the tree, Davey Tree Service Arborist Adam Passo uses a sounding hammer.

Passo said when he recently hit a boxelder tree in Washington County it made a hollow sound which indicates there is decay inside the tree.

He said that particular tree also has a crack with fungus growing out of it and has lost its tip branches.

“This tree really needs to go sooner rather than later," said Passo. "It’s alive, but it’s dead basically."

Passo said trees like this pose several risks.

(Spectrum News 1/Phillip Boudreaux)

“They will structurally fail generally before you can tell anything is going to happen, so winds come out of nowhere," said Passo. "They break it apart.”

Passo encourages anyone concerned about the condition of their trees to call an arborist.

He said depending on the situation, wood rods can be used to extend the life of a tree but removal or replacement are also options.

“I have seen a lot of devastating things, a lot of houses with trees in them. People hurt by trees. Vehicles crushed by trees, so trees are big. Some of the biggest living organisms in the world so you have to keep an eye on it. They are beautiful. They help with the environment a lot, but they also pose a hazard if left unchecked for too long.”

That’s why Passo hopes people will always keep an eye on their trees, so they are not dealing with a costly problem in the future.