Piles of Flour Under the Floor? Powder Post Beetles.
Found fine dust piles and pinholes in your hardwood floors? It's not termites. It's Powder Post Beetles. Learn how to identify and treat the 'shot holes'.
Finding a small pile of fine, flour-like dust beneath hardwood flooring or antique furniture is a specific diagnostic sign. It points not to termites, but to Powder Post Beetles.
The key difference lies in the waste material. Termites consume wood and typically hide their activity, bringing mud into the tunnels. Powder Post Beetles, specifically those in the Lyctid family, eject a very fine, dry powder (frass) that accumulates in small mounds below the wood.
The "Shot Hole" Sign
Above these dust piles, you will typically find small, perfectly round holes, roughly the size of a pinhead. These are known as "exit holes."
The damage is actually caused by the larvae, which tunnel inside the wood for months or even years. The hole appears only when the adult beetle emerges to mate. Therefore, seeing the hole means the internal damage has already occurred.
Treatment Options
Determining if the infestation is active is crucial. If the dust piles are fresh and bright in color, the beetles are still at work.
For furniture or isolated pieces of unfinished wood, a borate-based product (like Boracare) is highly effective. It penetrates the wood fibers and kills larvae as they feed. However, if the infestation is widespread in the structural beams of a home, surface treatments may not penetrate deeply enough. in those cases, professional structural fumigation is often the only way to ensure total eradication.