Frass is the word entomologists use for insect poop. Termite frass is composed of digested wood and bacteria that breaks down cellulose. Depending on the species of termites, frass appears as sawdust or small wood-like pellets. Termite infestations can exist for months without detection. Being able to recognize termite frass can help avoid extensive damage. Termite frass is fed to termite larvae in order to introduce the wood-eating bacteria necessary for digestion. Termites live in large colonies, which means they produce a lot of frass.

Termite frass is essentially ‘kicked out’ of the colony. Holes are made in the wood through which the termites push out the frass. Termite inspectors look for frass in order to confirm the location of a colony. This can be expecially useful, as termites may colonize areas that are hidden behind walls . The species of termite can also be deduced from the characteristics of the frass. Subterranean termites secrete round pellets, while the frass of drywood termites appears more like sawdust. Frass may be visible in piles close to baseboards, in corners, and inside walls. Frass is not toxic, and can be easily cleaned up. Sometimes frass plugs up the ‘kick out’ holes. Tapping the wood can dislodge the frass. Frass is a clear indication of an infestation.