formosan termite photo


  • Size: The typical Formosan alate (i.e., winged termite, or swarmer) measures around one-half of an inch in length, wings included.
  • Color: Formosan swarmers are yellowish-brown.
  • Behavior: Formosan termites are always hungry, and they eat wood. A lot of wood. They don’t care if it’s a dead tree on the ground, a live tree in your yard or the wooden structural components of your house. It really doesn’t matter to them. With possibly more than 10 million mouths to feed in their colonies, Formosan termites just want a substantial source of food, and that’s a 24/7 operation.

    Formosan termite workers are the colony members that seek out, masticate and digest wood. They then feed the entire colony by a process called “trophallaxis.” They digest and regurgitate the digested materials for the other colony members to eat.

    Termites are basically blind. They seek out wood or any other source of cellulose in a random manner. They expand their search from their nest until they bump into an acceptable food source.

    They are able to distinguish between light and dark, which is all they need to know for their safety. If they stay in the dark, they are safe from predators and able to maintain moisture in their fragile bodies. Light means danger.

    Mud tunnels, also known as shelter tubes or mud tubes, enable Formosan termites to maintain the temperature and humidity of their environment. These tunnels also help keep them hidden from ants, spiders and other predators that may come looking for trouble. Everywhere they go, Formosan termites build mud tunnels for safe travel, even below ground where their nest and many foraging tunnels are located.



When Formosan termites find larger pieces of wood, like the wood in a home, they work on the surface first. The mud tunnels are easy to see when on the surface of wood, but they usually remain hidden inside walls or behind other materials within the structure.

As they continue to feed, they bore into the wood where they do not need to build mud tunnels. The wood protects them while they feed, as long as they leave the surface intact. They take mud with them wherever they go to plug holes that may open up as the wood is destroyed, which is another sign of infestation.

Wood that has been attacked by Formosan termites appears wavy on the surface. This is referred to as a “ribbed effect” that is created as they eat the softer part of the wood growth rings, leaving the more dense part of the ring behind.


Tips for Control

If you should see termite mud tunnels, wood in your home that has a wavy or “ribbed” appearance on the surface or other evidence of termites, you should have it inspected by a professional. Formosan termites can damage wood at a much faster rate than the more common eastern subterranean species. They are very aggressive feeders and their colonies have five to seven times as many members as eastern subterranean termites.

Formosan termites will cause extensive damage to a home if left unchecked. If you see evidence of termites, call Terminix® to stop them in their tracks. If you are looking for preventative measures, you should:

  • Use wood that is pressure treated with preservatives. This wood is more resistant to attack by termites.
  • Address moisture issues in your home. Typical problems include leaks, plumbing, condensation and drainage issues.
  • Eliminate any areas where wood touches soil in, on and around your home.
  • Keep firewood, lumber and other wood debris away from the foundation of your home.
  • Schedule regular termite inspections for your home.