Asian Longhorned Beetle

Adult Asian Longhorned Beetles can be seen from around May to October. These invasive pest lay up to 70 eggs before dying and depositing each one in its own site just beneath the bark.

When the larvae hatch, they eat their way through the tree, girdling stems and branches and causing structural damage. After the larvae pupate, they tunnel out of the tree, leaving a hole (3/8 inch and larger) when they exit. Eventually, this damage kills the tree.

Asian Longhorned Beetles attack many hardwood trees including:

• Maples
• Horse Chestnuts
• Birches
• Williows
• Elms
• Poplars
• Green Ash
• Black Locust

Since the beetle spends most of its life inside the tree and out of our sight, it is difficult to spot. Look instead for signs of its presence:

• Unusual die-back of branches & limbs
• Oval or round shallow pits in the bark (these are egg sites)
• Oozing sap
• Piles of frass (looks like sawdust) around the base of the tree or in the crooks of branches
• Round holes (3/8 inch in diameter or larger) on the main trunk or branches

The only way to destroy the beetle is to cut down, chip, and incinerate the infested tree. Do not attempt to dispose of infested trees yourself! Instead, contact the Department of Agriculture in your state. You can start with your local Master Gardener or Local County Extension Agent to get you going in the right direction.