Tremex Wood Wasp

**This organism is not known to be present in the United States but poses a threat. The tremex wood wasp is native to Asia, where it attacks sick and dying trees mainly in the poplar and willow families. Outside its native range, however, it attacks healthy trees and can cause severe damage, mortality and economic loss. In Chile it attacks healthy poplar and boxelder trees, ruining their wood for lumber and removing windbreaks that protect agricultural fields. It has also caused damage in Australia since its introduction there. During oviposition, the female introduces a fungus into its host tree that rots the wood; the larval wasps then eat the fungus-infested wood, further damaging the tree and its lumber. Tremex wood wasp is not known to be in the US, but poses a serious threat should it be introduced, especially in the northeastern and western portions of the US where willows, poplars, cottonwoods and aspen are common. This species will also feed on maple, birch, locust, hop hornbeam, beech, walnut, sycamore, elm, apple and pear trees.


The tremex wood wasp was introduced to Chile in wooden packing crates; the insect spends most of its life inside trees and is difficult to detect. Potential introduction pathways to the US include wooden shipping materials (pallets, dunnage, etc.) and imported wooden products. If introduced, eggs could be transported unknowingly in firewood and pallets, and adults can fly several kilometers.


Think you've spotted this pest?

If you think you've found this pest in your landscape contact your local extension office to see about sending in a sample.
Find your local extension office here.