Old House Borer
  OHB Larva

Infestation signs


Pest eradication


     - chemical


     - biological


     - LesvinŽ

  Wood preparation
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Typical signs of infestation



One or two beetles found in your house, do not necessarily indicate an active infestation. They may come from outside. It is not often that a homeowner actually finds adult old house borers in a structure.



The clicking or rasping sound of the larvae feeding with wood can be heard from infested timbers, especially during spring and summer months when temperatures are high. That annoying voice can be heard through all year within closed heated rooms.

Exit holes


Old house borers leave an oval exit hole (0.6 - 1 cm), often with ragged edges. Powderpost beetles normally leave smaller round exit holes (0.1 - 1 cm). The presence of emergence holes indicates that some beetles completed their life cycle in the wood. Exit holes provide hints about the type of beetle and current activity.







Frass looks like fine sawdust. It is usually packed together with excrement inside timbers. If wood is infested, pale-coloured frass of active larvae may fall from the exit holes, forming small piles on the surface below the wood. If frass piles are swept away and more appear in a week or more, the infestation is still active.