Termite Droppings and Damage: How to Identify Them
Found tiny pellets or suspicious wood damage? Here's how to tell termite droppings and damage from the harmless stuff — and what each clue is really telling you.
Drywood termite droppings (frass) are tiny, uniform six-sided pellets that look like coarse sand or ground pepper, piled directly below infested wood — sawdust, by contrast, is irregular and stringy. Subterranean termites leave pencil-width mud tubes on the foundation instead of pellets. Termite damage shows up as hollow-sounding wood, blistered paint, spongy floors, and sticking doors, usually after activity has been going on a while.
Termites do their damage out of sight, so the clues they leave behind are how most people first catch them. The two biggest are droppings and damaged wood — and knowing what each looks like tells you a lot before an inspector ever arrives.
What termite droppings (frass) look like
Drywood termites keep their galleries clean by pushing waste out through small “kick-out” holes, leaving little piles of pellets called frass. The pellets are tiny, uniform and six-sided, ranging from tan to dark brown depending on the wood, and they look like coarse sand or ground pepper. You'll usually find a small mound on a window sill, a baseboard, the garage floor, or any flat surface directly below infested wood.
Frass vs. sawdust — how to tell them apart
This is the question we get asked most. Termite frass is remarkably uniform — every pellet roughly the same size and shape, with six flattened sides. Sawdust and carpenter-ant shavings are irregular and fibrous; carpenter-ant debris may include insect fragments. Powderpost beetles can leave fine, flour-like powder near round exit holes instead. If the “sawdust” is a neat pile of identical little pellets, it's almost certainly drywood termite frass.
Mud tubes — the subterranean sign
Subterranean termites don't leave frass — they reuse it inside their tunnels. Instead, their tell is the mud tube: a pencil-width tube of soil and saliva running up a foundation, pier or garage wall, built to keep the termites moist as they travel from the soil to the wood. A mud tube means subterranean termites, which are treated in the soil with bait stations rather than the spot or tent methods used on drywood.
What termite damage looks like
Termites eat wood from the inside out, so the surface can look fine while the inside is hollowed into galleries. Watch for wood that sounds hollow or papery when tapped, paint or veneer that ripples and blisters as if there's moisture underneath, sagging or spongy floors, and doors or windows that suddenly stick. Because so much of the damage is internal, visible signs usually mean activity has been going on for a while.
What each clue means for treatment
Evidence is not just evidence — each kind points at a different colony in a different place, and therefore at a different treatment. This is the whole map in one table.
| What you found | What it means | What it usually leads to |
|---|---|---|
| A small pile of hard, uniform six-sided pellets | Drywood termite evidence from the wood above; pellets alone do not establish current activity | Localized no-tent treatment when the activity is limited and accessible; fumigation when it is widespread |
| A pencil-width mud tube on the foundation, a pier, or a slab edge | A subterranean colony in the soil, tunnelling up to reach wood | In-ground bait stations plus targeted treatment at active entry points — a tent does nothing to a soil colony |
| Damaged wood packed with soil rather than clean and hollow | Subterranean damage — they carry soil into the galleries | Bait stations plus correcting the moisture that fed it |
| Piles of identical shed wings on sills or in webs | A mature colony nearby released swarmers; the wings are what they drop | An inspection to identify which termite and locate the colony |
| Hollow-sounding or blistered wood with no pellets in sight | Possible hidden activity, or damage left from an old infestation | Inspection — sounding and probing the wood is the only way to tell active from finished |
| Irregular, stringy sawdust mixed with debris | Possibly carpenter-ant debris or ordinary sawdust; powder near round holes suggests wood-boring beetles | Identification first, before anyone treats anything |
What to do if you find these signs
Don't clean it all up just yet. (For the complete catalogue of termite evidence — including kickout holes, mud tube types, shed wings and the look-alikes that fool people — see the termite evidence guide.) Collect a small sample of the pellets or take a photo, note exactly where you found it, and avoid spraying the area — those details help pin down the type and location. Then get an inspection. Identifying drywood vs. subterranean is what determines the fix: localized drywood often calls for no-tent spot treatment — here is how that compares to tenting — while subterranean calls for in-ground bait stations. Ask for a free quote if you've spotted any of these.
Quick Answers
Quick Answers.
What do termite droppings look like?
Drywood termite droppings, or frass, are tiny, uniform six-sided pellets that look like coarse sand or ground pepper, in colors from tan to dark brown. They collect in small piles directly below infested wood — on sills, baseboards or the garage floor.
How do I tell termite droppings from sawdust?
Frass is uniform — every pellet about the same size, with six flattened sides. Sawdust and carpenter-ant shavings are irregular and stringy, often mixed with debris. A neat pile of identical little pellets points to drywood termites.
Do all termites leave droppings?
No. Drywood termites kick out frass through small holes, so you see the pellets. Subterranean termites reuse their waste inside their tunnels, so instead of frass they leave mud tubes on the foundation. Different sign, different termite.
Should I clean up the droppings I found?
Save a small sample and note where it was first, then it's fine to clean up. Avoid spraying the spot. Those details help identify the type and find the source, which is what an inspection needs.
How much damage can termites do before I notice?
A lot — they work silently inside the wood for months or years before surface signs appear. That's exactly why frass, mud tubes and hollow wood matter: by the time they show, there's usually an established colony to deal with.
How do I know if termite damage is active or old?
Photograph the spot and save a sample before cleaning up. Sweep the pellets away completely, note the date, and check the same spot in a week or two. New pellets may indicate activity, but building vibration can also dislodge old pellets. Pellets alone cannot confirm whether a colony is active or how far it extends; an inspection is needed. Pellet colour is not a reliable clue, because it tracks the wood they ate rather than how fresh they are. For mud tubes, break open one small section: cream-coloured workers inside mean the tube is in use, while an empty crumbling tube may be abandoned. Old damage still matters, because it tells an inspector where the house is vulnerable.
What treatment do termite droppings mean I need?
Pellets point to drywood termite activity, but do not by themselves confirm a live infestation. Confirmed drywood infestations are treated in the wood itself. When the activity is limited to areas an inspection can find and a drill can reach, the treatment is localized injection: a termiticide foam is put straight into the galleries through small drill holes, in one visit, with you still at home. Whole-structure fumigation is reserved for drywood activity that is genuinely widespread or hidden beyond reach. Pellets never point to bait stations, because drywood termites never travel through soil.
Where do termites usually leave droppings in a house?
On any flat surface directly under infested wood. The common spots are window sills and the floor beneath them, along baseboards, on the garage floor under the door header or the framing, on a patio slab beneath a patio-cover beam, and in the attic on top of insulation or stored boxes. The pile matters less than what is above it: the kickout hole in the wood overhead is where the colony actually is, and finding that hole is what an inspection is for.
Sources
- UC IPM: Drywood Termites — University of California descriptions of drywood pellets, kickout holes and damage patterns.
- UC IPM: Subterranean and Other Termites — mud tube construction and soil-packed damage.
- UC IPM: Wood-Boring Beetles in Homes — powder and exit-hole patterns that help distinguish beetle evidence.
About the Author
Joshua is the owner and licensed operator of ExterMetro Termite and Pest Control in Arcadia, CA. He holds California SPCB Company Registration #8828 (Branch 2 & 3), is a licensed WDO inspector, and has worked San Gabriel Valley homes and businesses for over twelve years — hands-on in the field on every kind of job the valley throws at him.
Think you just found termite evidence?
Bag a few wings or pellets, snap a photo, and text it to (626) 409-1584 — quotes from photos are free, and your job stays under licensed ExterMetro oversight from inspection through follow-up.