Against the wood termites that reduce dust beams, furniture and logs are a good remedy boric acid-based baits that you can make yourself. Boric acid is available in pharmacies and parapharmacies, on the other hand you only need a little condensed milk.
Preparation of the baits. Pour the boric acid into a container (preferably plastic and not metal) and add the condensed milk, stirring with a spoon until you get a soft and homogeneous mixture that you can manipulate with your hands.
Once the dough is made, put on some latex or plasticine gloves and model with your fingers some balls of about 1 cm in diameter even smaller: these will be your baits for termites that you will position in the points from where it is necessary to drive them away, preferably near the nest.
The wood termites they will be attracted by the smell of condensed milk, they will approach the bait and begin to eat them. Boric acid, which is a common household antiseptic but is lethal to termites, will act as an insecticide but without the drawbacks of the toxic substances contained in the various sprays and powdered products.
The effectiveness of the bait does not depend so much on the amount of boric acid that it contains termites workers are able to swallow as much as by what they are able to transport inside the den available to the queen. This is how the colony can be eradicated.
Of wood termites there are two types: the real ones of wood, which are visible and leave traces of sawdust and holes in the wood as they pass, and the underground ones that instead live in the earth, are not seen until they have already done the damage and they irreparably attack wooden beams and structures but also the trunk of trees.
Speaking of trees, it must be said that the wood termites (especially the underground ones) perform the important natural function of 'demolishing' dying trees when they are too old or weakened by diseases or fungal attacks. More rarely they attack healthy trees, but when this happens they can crumble the inside of the trunk even before their presence is noticed from the outside.
Since the wood termites they eat and are greedy for cellulose, a very simple empirical system to check their presence is to place small pieces of wet cardboard in the sensitive points. If the termites are there they will not be able to resist.
Boric acid can also be used against ants, for which there are also other remedies.