Typically running from April until September each year, what is commonly known as “woodworm” season is in full swing, so homeowners should keep a close eye out for these woodboring pests.
The term “woodworm” refers to the larvae of various species of beetle that will bore into any wooden surface, and while the damage can be cosmetic, sometimes woodworm can cause devastating problems to furniture and structural timbers.
In this, the second instalment of our “woodworm” series, we’ll explore the third most common species – the Deathwatch beetle. We’ll also advise on the telltale signs of “woodworm” activity in your home, following last month’s guide on “woodworm” life cycles.
Deathwatch Beetle (Xestobium rufovillosum)
The Deathwatch beetle can be the most damaging wood borer in old buildings. It attacks hardwoods, most commonly oak and elm. It will occasionally attack softwoods, if they are in close contact. For an infestation to start, the timbers must also suffer from fungal decay.
Deathwatch beetles are larger than the Common Furniture beetle. They are greyish brown in colour with patches of yellow hairs and measure on average 5-7mm in length. Adults are able to fly, but normally crawl and produce flight holes of approximately 2-3 mm in diameter – larger than those of the Common Furniture beetle.
The Deathwatch beetle earned its somewhat morbid name because it was often heard by people “on watch” with a sick person on their deathbed. The beetle makes a tapping sound when it strikes its head on the surface of the timber. Damage from Deathwatch beetles is more prevalent in the UK compared to other countries as many historic timber framed buildings are built from hardwoods such as oak or elm, the favoured food of the larvae. The buildings’ great age means they often fall into disrepair, the timbers become damp and then affected by fungal decay.
One beetle can lay between 40 and 60 eggs singly or in small groups in dark crevices in old wood and inside tunnels bored by previous larvae. Deathwatch beetle larvae bore into the wood, feeding for six to ten years before pupating, and later emerging from the timber as adult beetles. The emergence period for Deathwatch beetles is April to June.
Spotting the signs of “woodworm”
The Deathwatch beetle is one of many species referred to as “woodworm” that commonly occur in the UK. It’s important residents are able to recognise the telltale signs of any “woodworm” activity, and call in the experts to treat the issue before significant damage results.
In general, signs of “woodworm” activity include:
1. Small round exit holes – Holes between 1 and 6mm diameter in the timber surface are perhaps the most obvious sign of a “woodworm” problem. These flight holes are created after the woodworm larvae pupate and hatch into adult beetles, boring their way to the surface of the timber to mate.
2. Fine, powdery dust – ‘Frass’ is the term given to the small, fine and powdery dust that is often found near “woodworm” exit holes. Frass refers to the droppings that the larvae produce as they burrow and chew their way through wooden structures. If you see any ‘exit holes’ in wooden items or timber then be sure to check frequently for evidence of frass, because this is a key sign that the infestation site is currently active. Deathwatch beetle frass is dark and disc or donut shaped.
3. Tunnels within the timber – If the surface breaks off, it may be possible to see a network of small tunnels that have been bored into the wood by the larvae as they burrow inside.
4. Weak or damaged timber or floorboards – If you have noticed wooden furniture, flooring or structural timber is noticeably weaker or started to crumble at the edges, then it could be a sign of “woodworm”.
5. Beetle activity (dead or alive) outside of timber – If you notice beetles emerging from timbers, or dead beetles close to holes then you more than likely have a “woodworm” infestation.
If you notice any of these signs in your property, then please visit our woodworm treatment pages to discover how our woodworm experts can help you.
Stay tuned for the next instalment in our woodworm series in July, where we’ll be talking about the woodboring weevil.