While termites get most of the attention, wood-boring beetles cause significant structural damage in Southern California homes — and most homeowners have never heard of them.
What Are Wood-Boring Beetles?
Wood-boring beetles are a group of insects whose larvae develop inside wood, feeding on cellulose and starches as they grow. The most common species in Southern California include:
- Anobiid Powderpost Beetles (furniture beetles)
- Lyctid Powderpost Beetles (hardwood borers)
- Bostrichid Beetles (false powderpost beetles)
- Old House Borer (Hylotrupes bajulus)
Unlike termites, wood-boring beetle damage can take years to manifest — larvae may spend 2–10 years inside the wood before emerging as adults.
How to Identify Wood-Boring Beetle Damage
Exit Holes
The most visible sign is small, round exit holes (⅛ inch or smaller for most species) left when adult beetles emerge. These holes are perfectly round, unlike the irregular damage termites create.
Fine Powder (Frass)
As larvae tunnel through wood, they produce fine powder-like frass that falls out of exit holes. Unlike drywood termite frass (which is pellet-shaped), beetle frass is smooth and powdery.
Live Adults
Adult beetles may be found near windows or lights after emergence, typically in spring and early summer.
Where Beetles Attack
Wood-boring beetles target different types of wood depending on species:
- Lyctid beetles: Attack hardwoods like oak, ash, hickory, and walnut (furniture, hardwood floors)
- Anobiid beetles: Attack softwoods including pine framing, structural members, and plywood
- Old House Borer: Specifically targets pine and softwood structural lumber in older homes
Structural Implications
In severe or long-term infestations, wood-boring beetles can compromise structural members, floor joists, and framing to the point of failure. The damage is cumulative — each generation of larvae causes additional tunneling.
Treatment Options
Borate Treatment (BoraCare/Tim-bor) is highly effective against wood-boring beetles. When applied to bare wood, borates penetrate deeply and kill larvae inside the wood as they feed. BoraCare has a residual effect that prevents future infestations.
Fumigation is the most complete treatment for widespread beetle infestations, penetrating all wood in the structure and killing all life stages including eggs and pupae deep inside the wood.
For localized infestations in furniture, heat treatment can raise temperatures to lethal levels without chemical use.
Inspection and Next Steps
If you notice exit holes, powdery frass, or suspect wood-boring beetle activity in your Southern California home, contact our team for a professional inspection. We service all cities in Orange County, Los Angeles, Inland Empire, and Riverside County.