There are two types of borer – the common house borer and the much rarer two-tooth long-horn borer.
The easiest way to identify which one is affecting timber is to look at the holes they leave: the common house borer leaves a small round hole, the two-tooth long-horn borer an oval hole up to 5 mm long.
Both types of borer lay their eggs on a rough timber surface or in cracks or holes. The larvae bore into the timber, sometimes for up to four years. As adults, they bore their way back to the surface. Fresh holes and dust that appear between November and March indicate that the infestation is still active.
The adults are airborne for about a month between November and March, to mate before the cycle starts all over again. Two tooth borer can remain in the wood for up to 11 years before exiting in autumn. Damage is usually severe from two tooth borer and timber will often have to be replaced. Because two tooth borer will also attack living trees, they can be more common in bush clad areas.
Infestation by the common house borer generally tends to cease before timber becomes structurally unsound because of these borer attack only the sapwood in the timber – most framing timber has sufficient heartwood to avoid serious weakening.
They are often found on the south side of buildings or in-floor timbers because these areas are prone to damp. They are also fond of soft (sapwood) or untreated wood and can be common in untreated native timbers in older homes. It is not uncommon to have borer attacks on some boards and not others.
The eggs take 4-5 weeks to hatch and the larvae then bore into the wood, where they stay, chomping away for up to four years.
We will also leave you with a comprehensive report and recommendations on housekeeping, proofing, and exclusion to help eradicate and control borer.