These termites cause more damage at faster rates than drywood termites. They don't leave frass droppings like drywood termites. The St. Augustine Record: What are the signs of a termite infestation?

which may be accompanied by small piles of sawdust-like droppings, called frass. Drywood termite-damaged wood has a smooth ...

Termites typically found in California include drywood, dampwood and subterranean ... when tapped or shows signs of damage ...