Wood Wasps

Facts, Identification & Control

The horntails or wood wasps are in the wasp family Siricidae.


Their common name is appropriate because they have long body parts that extend out from the back of the abdomen (tail). While horntails resemble typical wasps, these projections are not stingers, but are used by the female wood wasp to lay her eggs in trees that are weakened or dying. Therefore, this wasp does not sting and inject venom or bite pets or people. Wood wasp adults are fairly large, being from about ½ to ¾ inches long. They will infest both hardwoods and softwoods.

Life Cycle

The wood wasp’s life cycle begins with a fertile female adult drilling into the tree’s bark and then using her ovipositor to lay eggs. When the eggs hatch, the wasp larvae bore further into the tree, living there for as long as 2-3 years. When the insect’s pupal stage is complete, adult wasps emerge after chewing through as much as an inch of wood and bark. Evidence of emergent adults includes the exit hole they leave behind.


Wood wasps do not sting, but they may cause other problems for the homeowner. Although they do not re-infest seasoned wood such as lumber, their long life cycle may create a situation whereby live larvae remain in logs that are sawed into lumber. When the larval and pupal stages are complete, adults are able to emerge inside the home.

Also, wood wasps may be introduced to the inside of the home when infested firewood is brought inside and not used for a while.

Should wood wasp control be required, contact your pest management professional for advice about what is required to eliminate a wood wasp problem.