Look Out for Woodworm
There are two major threats to the structural timbers of a house, rot and woodworm. And if you are unlucky enough to discover signs of damp or rot in your home, it would be very advisable to check for woodworm too. Some of the woodworm pests responsible tend to prefer damp, and sometimes decayed wood.
A mild attack of woodworm can be dealt with effectively simply by painting the damaged area with a proprietary woodworm fluid but if the damage is severe, and the inside of the wood has been seriously weakened, the timber must be cut out and replaced before the infestation spreads.
Types of woodworm
Woodworm is a collective name given to a variety of wood-boring insects whose grubs or larvae feed on timber.
The adult furniture beetle is a small brown insect, about 3mm long, which can fly into a house or be introduced by old packing cases, wicker baskets or secondhand furniture. The female beetle lays up to 60 eggs in cracks and crevices of structural and joinery timbers and furniture. After about three weeks grubs hatch from these eggs and bore down into the wood, leaving no trace.
Inside the wood they tunnel, feeding on the wood continually, for three years or more. They then make small cavities near the surface of the wood in which to pupate. After two to three weeks the fully formed adult beetles emerge. Biting their way out of the wood to leave the characteristic round ‘flight’ holes about 2mm across. Fresh holes show clean, white wood inside. A small amount of fore dust may be detectable around the holes.
The death watch beetle is much rarer than the furniture beetle as it is flightless and limits its attacks to old hardwood. However, it has a very long life cycle. The grub bores in the wood for up to 15 years before emerging, during which time it can do immense damage.
The woodboring weevil is also found through out the world especially in New Zealand and port areas of Australia and is on the increase in the UK. It attacks most types of wood but fortunately the female lays only one egg and the larval stage is short – from 6-8 months.
The powderpost beetle confines its attacks to the sapwood of hardwoods, so only fresh wood is at risk. It, too, has a relatively short life cycle, only boring in wood for about 10 months.
Checking for Woodworm
The problem with woodworm is that an attack becomes apparent only after the adult beetle leaves the timber. Once flight holes appear you know that at least one generation of woodworm has attacked the timber and has gone on to repeat the cycle, usually within the same vicinity.
If your house is more than about 20 years old an extensive examination is quite likely to reveal signs of woodworm.
