Evidence signature
Larger oval exit holes, coarse packed frass and feeding sounds in softwood framing.
The strongest identification comes from several independent observations that agree: the physical sign, its exact scale, where it accumulates and a companion clue. One isolated mark is rarely enough.
Most useful evidence
Frass and pellets, Holes and openings, Larvae and grubs, Sounds and movement, Damage and gnawing.
Typical locations
Attic and roofline, Wood and furniture, Walls and ceilings.
Common timing
Any, Seasonal.
Supporting context
Wood, Attic.
What supports this identification
- Oval rather than tiny round exit holes
- Coarse frass in galleries
- Softwood framing context
- Possible faint feeding sound
What points away from it
- Flour-like powder from tiny holes
- Uniform termite pellets
- Mixed ant shavings
Measure several holes and identify the wood member before assuming a beetle species.
A safe first response
Do not cut or weaken structural members.
Preserve a clear photograph with scale before cleaning when that can be done safely. Avoid broad pesticide applications until the target and exposure route are understood; an indiscriminate treatment can scatter activity, contaminate surfaces or obscure the evidence.
When to bring in a professional
Structural softwood activity should be assessed by a qualified wood-pest or building professional.
Common lookalikes
Powderpost beetle
Lyctinae and related groups
Tiny round holes with flour-like powder accumulating below unfinished or stored wood.
Drywood termite
Kalotermitidae
Uniform hard pellets in small piles directly below tiny wood openings, often recurring after cleanup.
Carpenter ant
Camponotus spp.
Coarse mixed wood shavings below a slit or crack, often with large ants and moisture-damaged wood nearby.
Direct comparisons
Side-by-side decision
Powderpost beetle vs. old house borer
Exit-hole diameter and frass texture are decisive: powderpost signs are tiny and flour-like; old-house-borer signs are larger and coarser.
Open comparison