What distinguishes drywood termites from subterranean termites is the fact that they do not need contact with the soil nor any other water source to survive and they do not build mud tubes. As their name suggests, drywood termites occur in dry wood that may be above ground level and the colony is rather small (a few thousand individuals).
In addition, drywood termites will evacuate fecal pellets from their galleries that are hard and six sided with concave surfaces. Piles or mounds of dark and light colored fecal pellets around doors and windows are visible sign of drywood termites.