Tunnels

• Termites create tunnels from the ground to the wood in the deck. These tunnels usually have a muddy appearance and are flat and about the width of a pencil. You can easily see the tunnels on exposed surfaces such as cracks in the concrete foundation of the deck.
  
  

Wings

• When termites look for mates, they swarm and shed their wings. Swarming termites find light attractive and often swarm near lighting fixtures. Large numbers of termite wings on the floors of the deck indicate a termite infestation.
  
  

Wood Damage

• Infested deck wood floors feel springy when you walk on them. If you tap on the wood using the handle of a screwdriver, some parts sound hollow because termites create galleries inside. Sometimes the screwdriver breaks through the wood and you can see the tunnels inside.