Powderpost beetle
Lyctus / Anobiid species
- Identification
- Small beetles whose larvae bore through wood, leaving tiny round exit holes and fine, flour-like frass.
- Lifecycle & behavior
- Larvae develop inside seasoned wood for months to years; adults emerge, leaving exit holes, and reinfest.
- When it's active in Central NY
- Found in CNY hardwood flooring, framing, furniture, and barn wood; emergence and fresh frass are typically noticed in spring and summer.
- Risk & damage
- Progressive damage to hardwoods and structural members; one of the wood-destroying insects a WDI inspection reports.
- Why DIY falls short
- Surface treatment doesn't reach larvae deep in the wood, and infestations can smolder unseen for years.
- How we treat it
- Inspection to gauge activity, appropriate wood treatment, moisture correction, and WDI documentation when needed.
Powderpost beetle or old house borer?
Exit hole size separates them at a glance. Powderpost beetles leave small round holes roughly the diameter of a pencil lead — about a sixteenth to an eighth of an inch — with fine, flour-like frass that feels genuinely powdery between the fingers. Old house borers leave much larger oval holes, about a quarter to three eighths of an inch, with coarser, gritty frass.
Wood type is the other clue: powderpost beetles attack hardwoods, so flooring, trim, furniture, and hardwood structural members. Old house borers attack softwood framing.
Powderpost beetles in Central New York
In this region powderpost beetles turn up most in older homes with hardwood flooring, trim, and exposed hardwood framing, and in antique furniture — all of which the area's housing stock supplies abundantly. They can also arrive in newly milled hardwood or reclaimed lumber that was infested before installation.
The critical question with any hole-in-wood finding is whether the activity is current or historical. Fresh, pale-colored frass that keeps reappearing after you clean it away indicates an active infestation; old holes with darkened edges and no new frass may be decades dead. That distinction determines whether treatment is needed at all, and it is worth having someone look before assuming either way.
Dealing with powderpost beetle?
Our wdi / real estate pest inspection handles it — guaranteed, family-owned, and local.
Powderpost beetle — common questions
How do I know if the holes in my floor are old or active?
Clean the frass away completely and mark the date. If fresh, pale, powdery frass reappears over the following weeks, the infestation is active. Old holes with darkened edges and no new frass may be long dead. That single test decides whether treatment is warranted.