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Loved by nature lovers, feared by firewood owners. The longhorn beetle may look fascinating in the wild, but it can cause serious damage when it infests stored logs. In this article you will learn how to identify, prevent and control this wood-boring insect.

What Is a longhorn beetle?

The longhorn beetle is a wood-boring insect similar to the common furniture beetle (woodworm). The house longhorn beetle (Hylotrupes bajulus) is especially known for its destructive larvae, which tunnel deep into timber for years.

While they typically affect structural wood such as roof beams or floorboards, they can also infest firewood, particularly if it’s damp or poorly stored.

Several longhorn beetle species can infest stored logs, including:

• House longhorn beetle (Hylotrupes bajulus)
• Fire-coloured longhorn beetle (Pyrrhidium sanguineum)
• Red-shouldered longhorn beetle (Stictoleptura rubra)

How to recognise longhorn beetle damage?

Signs of infestation include:

• Oval or uneven exit holes in the wood surface.
• Fine powdery frass (wood dust) around the holes.
• A dull, hollow sound when tapped.
• Soft or weakened timber.
• When splitting logs, you may find wide tunnels or large, cream-coloured larvae. This is evidence of longhorn beetle activity.

Can you still burn infested firewood?

Yes, but there are drawbacks:

• Infested logs burn faster and produce less heat.
• Larvae may spread to other firewood.
• House longhorn beetle larvae can move on to processed or structural timber inside your home.

Preventing longhorn beetle infestations

Because the larvae live deep inside wood and can remain hidden for years, prevention is key.

• Keep firewood dry and well-ventilated.
• Store logs under a roofed, airy shelter.
• Avoid stacking wood directly on damp ground.

What to do if you discover an infestation?

If you spot signs of longhorn beetle activity:

• Separate infested logs from the rest of your pile.
• Burn affected wood as soon as possible. The heat will kill the larvae.
• Inspect nearby timber for further signs of damage.

If you suspect the house longhorn beetle has spread into your property, contact a professional pest control specialist for safe and effective treatment.