Delta is a large sand pile that ants love, especially carpenter ants. These ants prefer to invade wet and rotting wood that has been softened by fungus and are often associated with moisture problems. When you have carpenter ants the only external sign of an infestation other than the presence of workers (all female like a sisterhood) is the appearance of small perfectly round holes on the surface of wood. Through these exit holes, the ants eject wood frass, which consists of sawdust and parts of dead sisters. The build-up of this frass below the holes is a excellent indication of an active carpenter ant infestation.
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