The term woodworm is an umbrella name for several insect larvae living in wood. Most commonly known is the larva of the common woodworm beetle, also known as the skullcap. Woodworms can – as you can see from the name – cause a lot of damage to woodwork. Fighting woodworm is therefore the only solution to get rid of the problem.
A woodworm is a larva of a beetle. So if someone is bothered by woodworm in the house or in the garden, then this person is actually bothered by beetle larvae. Now there are several beetles that have larvae that hide in wood. The woodworm does not exist.
The best known beetle that can provide larvae that hide in wood, is the ordinary woodworm beetle, Anobium punctatum. This beetle is related to the beating beetles. The common woodworm beetle is also known by a few other terms such as the knock beetle, small woodworm beetle or furniture beetle.
Living area of woodworm in the Netherlands
The common woodworm beetle is found worldwide. From Europe and Asia, to North America and Australia. The woodworm – or common woodworm beetle – does not have a preference for a certain area in the Netherlands. You can find this insect anywhere where there is dry and unprocessed wood where the larvae can survive for several years.
Outer characteristics of woodworm
The common woodworm beetle can be recognised by its size, about 2.5 to 5 mm, and the fact that it has a dark brown and a vaulted neck shield. On this shield rows of small dots are visible.
The larva of the common woodworm beetle is on average 6 mm long, yellowish in colour and slightly curved. You are more likely to encounter the beetle than the woodworm itself, as it is deeply hidden in the corridors in the wood.
Other beetles that also produce larvae that need wood to live in are, for example, the larvae of the variegated gnawing beetle or variegated knotweed, which is also called large woodworm. Or the domestic longhorn beetle which can cause severe damage to indoor woodwork, but which is usually not referred to as woodworm.
Living and eating
The woodworm drills holes in wooden structures in order to be able to hide from danger and enemies in the outside world, but also to be able to feed on the wood that is released during the digging of the corridors. The beetle larvae remain in the wood until they are ready to pupate, after which they will eventually fly away as a beetle.
Processed wood does not like the wood worm larva, so you will encounter them en masse on rafters, unprocessed furniture and works of art in houses. They have a preference for softwood, especially splintwood is often a victim of the woodworm.
Enemies of the woodworm
The wood beetle and woodworm do not naturally have any specific enemies aimed at hunting them. It is possible that a beetle or larva is eaten by, for example, birds looking for food. Other hostile insects that invade the woodworm can also be a danger to the woodworm.
Planting and lifespan
Adult beetles don’t eat, all they do is reproduce. The female of the common woodworm beetle lays her eggs in cracks in wood or in the holes in which beetles have been in before. After about 3 weeks the eggs hatch.
The larva that eventually emerges – so the woodworm – can then make their way through wood for about 3 to 4 years, where they reach a size of about 7 mm. When they are ready to pupate, they sit just below the surface where they stay for 8 weeks. The adult beetles continue to break through the surface. A hole of 1 to 1.5 mm remains, also releasing dust. Only when you see these holes, you can be sure that you are dealing with a woodworm layer. There are also other species of beetles that fly out from underneath a woodworm surface, but these holes are usually much larger than those of the woodworm beetle.
Nuisances and illnesses
The beetle larvae (i.e. the woodworm) drill holes in any kind of wood they encounter. As a result, they can damage or even destroy wood structures, floors, furniture and any other wooden object. Woodworms prefer to live in softwood. You can check whether the woodworms have recently been active in the wood by checking whether there is drill flour coming out of the holes. The round or oval openings in the wood are the escape openings of the beetles.
Woodworm is easiest to control through the use of chemical insecticides. Chemical pesticides dissolved in organic solvents or water can be used to make it less harmful to the environment. If you treat the woodworm in an expert and effective way, a new infestation by a new group of beetles will only occur after a long time. However, if you treat the wood inexpertly and sloppily, you will have a new group of woodworms in the wood within 5 years.
Whenever possible, it is better to destroy or dispose of the infested wood immediately to prevent a new group from living in it and to prevent them from spreading from the infested piece of wood to other furniture or woodwork.