Horntail Facts & Information

What Orkin Does

In most cases, it will not be necessary to do anything to control horntails. The adult horntail does not reinfest seasoned wood. It will not lay eggs in wood that is inside the home. Damaged wood can often be repaired or replaced.

Nevertheless, homeowners can help prevent infestation by storing firewood outside the home. Firewood should only be brought in when it will be used.

If infestation is suspected, homeowners are encouraged to request an inspection by an Orkin specialist to ensure any evidence of wood damage is not from authentic wood damaging insects able to cause structural problems.

Appearance

Horntails get their name from the projection on the back of their abdomen, which often is confused for a stinger. Some people refer to these insects as wood wasps, as horntail larvae bore into wood.

• Size: Depending on the species, adult sizes range between 12 to 40 mm.

• Color: They are dark colored, usually brown or black. Some species have pale markings.

Reproduction

Eggs

Female horntails deposit their eggs into the trunks of trees. Most species choose coniferous, softwood trees, but a few species choose broadleaf, hardwood trees. Chosen trees are usually in decline from disease or attack from other insects.

Larvae

When the eggs hatch, the larvae burrow into the wood. They pack tunnels with droppings and wood shavings as they burrow. When the larvae are mature, they burrow close to the surface of the wood and make a silken cocoon inside the tunnel, where they then change into adults.

Adults

In the forest, horntails can complete the entire life cycle in a year or two. If the wood has been dried and made into lumber, the horntail life cycle can take as long as five years. When the adult comes out of the cocoon, it chews its way out of the wood. The adult makes a round hole in the surface of the wood. The exit holes are usually about 1/4" in diameter.