Sterling Timber and Damp - Infestation Problems

Sterling Timber and Damp - Woodworm

Woodworm is not just one problem, the term refers to the larvae of any wood-boring beetle, rather than a particular species. In the UK, the most common are the Common Furniture Beetle (Anobium punctatum), Deathwatch Beetle (Xestobium rufuvillosum), House Longhorn Beetle (Hylotrupes bajulus) and Powderpost Beetle (Lyctus brunneus). All invade and consume wood, and then leave when they have reached maturity.
How do I know if my property is affected?

Your woodwork may be harbouring woodworm without you knowing it. Wood can be infected with eggs or larvae without it being noticeable, and you may not discover a woodworm infestation for several years. It's a common misconception that woodworm only affects old properties, in fact it can cause damage to newly constructed buildings.

Tell tale signs of woodworm include:

Small round holes in your woodwork, similar to the holes in a dart board.
Fine, powdery dust around these holes (this is known as frass).
Crumbly edges to boards and joists.
Adult beetles emerging from the holes or present around the house.

Even if you can't see any holes, you might also find frass escaping from the back or underside of old furniture. Again this suggests active woodworm.

However, not all of these signs of activity are cause for concern. Holes and frass might just indicate a previous woodworm infestation, long since dormant.

Dealing with a woodworm infestation

Even though you have holes in your timber it may not mean that you actually have a woodworm infestation now. If in any doubt at all, it is best to contact a specialist to ascertain the reality and the currency of the threat. At Sterling Timber and Damp, we have long prided ourselves on having the experience to recognise an infestation long since passed and the integrity to say so when that is the case.

If you do have a woodworm problem currently attacking your timber, we also have the expertise, materials and systems to deal with that infestation quickly, efficiently and cost-effectively.

Timing is vital, as the larvae burrow into your wood to pupate, then emerge several months later in about September as adults to start the cycle again. Treating in this pupating period is the best time to gain the upper hand, so call us on 0800 136 874 or email us by clicking the header of any page if you have any concerns.

Sterling Timber and Damp - Boring Beetle

Woodboring beetles are commonly detected a few years after new construction. The timber supply may have contained wood infected with beetle eggs or larvae, and since beetle life cycles can be one or more years, several years may pass before the presence of beetles becomes noticeable. If you have an infestation of woodboring beetles, it is best to consult a professional entomologist before contacting an exterminator. In many cases, the beetles will be of a type that only attacks living wood, and thus incapable of 'infesting' any other pieces of wood, or doing any further damage.[citation needed] In other words, only some types of beetles should be of concern to a homeowner (see list below), and exterminators may be unable or unwilling to make this distinction.

Genuine infestations are far more likely in areas with high humidity, such as poorly-ventilated crawl spaces. Housing with central heating/air-conditioning tends to cut the humidity of wood in the living areas to less than half of natural humidity, thus strongly reducing the likelihood of an infestation. Infested furniture should be removed from the house before the infestation spreads.

Dealing with wood boring beetle infestation.

Spot application of pesticides; however, most effective insecticides are obtainable only by certified professionals.
Freezing. Infested furniture may be wrapped in plastic and placed in walk-in freezers for several weeks.
Fumigation.

The best time to apply insecticides to wood is in spring (March-May) when the insects are near the surface of the wood, just before they emerge, and so are more accessible to the insecticide. The life cycle of most wood-boring beetles lasts more than one year, so that to achieve complete eradication it is essential to repeat the treatment each year until signs of the attack disappear.

In confined spaces, the use of insecticides to kill off the adults can help to prevent re-infestation, so the thorough answer is to treat the timber and follow up with a thorough fumigation.

Sterling Timber and Damp - Death Watch Beetle

The death watch beetle (Xestobium rufovillosum) is a woodboring beetle, namely a beetle whose larvae are xylophagous - they hatch and eat wood, having symbiotic protozoa and bacteria in their digestive system that help them break down and digest cellulose. The adult is approximately 7 mm long. The larva can be up to 11 mm long. For the larvae to flourish it is usually necessary for the heartwood to have been attacked by some fungal decay, which makes it more palatable for them.

To attract mates, these woodborers create a tapping or ticking sound that can be heard in old building rafters during quiet summer nights. They are therefore associated with quiet, sleepless nights and are named for the vigil (watch) kept beside the dying or dead, and by extension the superstitious have seen the death watch as an omen of impending death.

The term death watch' has been applied to a variety of other ticking insects including Anobium striatum, some of the so-called booklice of the family Psocidae, and the appropriately named Atropos divinatoria and Clothilla pulsatoria, however, it is the xestobium rufovillosum that is the cause of timber damage in our buildings.

In many historic British buildings the oak beams were converted and assembled while green. This led to high moisture retention making an ideal environment for fungal and death watch beetle infestation. In many of the larger timbers, this moisture content will have remained high enough to sustain fungal growth for many years. With subsequent water ingress and possibly a lack of maintenance, the situation can worsen. Condensation and poor ventilation can also heighten the chances of infestation by raising the moisture level above the 14% which is reckoned by a number of authorities to be the threshold level at which a colony becomes sustainable.

Identification and treatment

Like so many pests, death watch beetles are experts at survival, and the life cycle can vary between a year and up to twelve years depending on the circumstances. This means that a treatment needs to offer long term protection and penetrate deep into your timbers as that is where the larvae live, and it is the larvae rather than the adults that do the damage by eating your building.

The identification of the beetle itself is quite easy. The adults are 6-9mm long, dark brown with patches of yellow hair: the larva are up to 9mm long, cream and slightly curved, covered in fine yellow hairs. The flight holes and tunnels are circular and 3mm in diameter. The bore dust is cream coloured with bun-shaped pellets.

It is important to confirm whether a beetle attack is active or dead. It should always be borne in mind that the great majority of Death Watch Beetle attacks found in historic buildings died out many years - even centuries - ago. However, this has not stopped the unscrupulous from treating the attack by one system or another, and hailing the subsequent status quo as a success.

The extent of the attack within the timber is not always proportional to the number of flight holes visible, and the structural integrity of the timber should always be checked. Many visible attacks affect only the sapwood areas left on the outside of the timber after conversion, which has no structural significance: surface treatment will normally deal with this, but the attack has usually died out years ago.

The presence of fresh, brightly coloured bore dust and clean dust-free flight holes certainly indicates that the attack is active, but their absence may not necessarily mean that the attack is dead.