What has made these small holes in this rotting sycamore, Acer pseudoplatanus, stump? The holes range from 1-3mm in diameter and are numerous throughout the wood. Answer to follow next week....
Many of you may recognise these distinctive holes, indeed you may well have some of them in your own homes - but do you know exactly what has caused them...?
They are made by a species of beetle called Anobium punctatum, also known as the furntiture beetle or the woodworm. And indeed they are the little creature that make holes in furniture and wooden parts in houses and other buildings. The imago (adult) beetles are very rarely seen and are brown in colour, being around 2.5mm - 5mm long. They are active in late spring and early summer, when they mate and the female lays her eggs in crevices and old holes in wood. Once hatched, the larvae feed inside the wood, burrowing their way through as they grow. Development from hatching to pupation usually takes a minimum of two years and very much depends on the temperature and the type of wood on which the larva is feeding. Prior to pupation, the larvae burrows outwards and creates a chamber just below the surface of the wood in which pupation and metamorphosis takes place. On emergence the adult beetle then burrows out of the wood and it is this small emergence hole that you see in the photo above.
Anobium punctatum is a common and widespread species in the UK, being most common in the south and east. Their natural habitat is old, dead wood in woodlands, as is seen here in the above photo. However, they have adapted very well to live in man-made habitats.