The small holes you sometimes see in wood are called pinholes. These pinholes are made by insects. What insects cause these holes and what can you do about them?
What insects cause pinholes in wood?
Small holes in wood are caused by different types of insects. These insects are subdivided into wet wood borers and dry wood borers.
Wet wood borers
These insects live on the sap flow of trees and die as soon as the tree is cut down. Therefore, there is no longer any risk of new bites forming. You can easily recognize the pinholes:
- There are no piles of drill dust near the holes (the bugs are no longer active)
- The holes are almost always black or gray in color (just like wood, holes age too)
These insects live in dry, felled wood. They can stay in the wood for years and cause a lot of damage. You can recognize them by:
- A new pile of drill dust they leave on the wood or on the ground
- Holes in the wood that still have a fresh color
What can you do about holes in wood?
Wet wood borers
You don’t need to treat those pinholes because the bugs are gone.
Dry wood borers
You need to treat these bugs. Timely intervention and having a professional treat/combat it can prevent significant damage to woodwork. What you can try yourself is to treat the affected wood with a woodworm pesticide and wrap the treated area in cling wrap for a week. However, if it is a very expensive or monumental building, always take a professional look at it.
With larger holes, it can be the longhorned beetle. A longhorned beetle can even stay in the wood for up to 7 years before it flies away, that’s why there is no wood flour. Fortunately, a longhorned beetle is almost non-existent in the Netherlands. But it is important to treat the wood as soon as possible if this insect is in the wood.
Sometimes there are also holes in our wood. In 99% of the cases, these are wet wood borers. Do you see holes in the wood? Then take a look at this description and see whether or not you should be concerned and take action. Still not sure?
Frequently asked questions
What creates small holes in wood?
It’s not uncommon to notice little holes in wooden items inside properties at this time of year. You may also notice small piles of dust near them. This is likely to be the result of ‘woodworm’, or more accurately, the larvae of wood boring beetles 
What insect makes circular hole in wood?
What are Carpenter Bees? Carpenter bees get their common name from their habit of boring into wood. Carpenter bees do not eat wood but cause damage to structures by drilling circular holes to create tunnels inside wood 
How to get rid of wood borer
Wood boring beetles are attracted to the moisture content in the wood, try to keep furniture, door and wooden items dry.
Seal cracks and crevices on wood surfaces to deter wood borer from breeding.
Remove infected wood to avoid the infestation from spreading to another area