There are several products and treatment techniques on the market today.
Solid product treatments consist of inserting rods inside the pole. These rods will dissolve in contact with the internal moisture of the pole, and will diffuse for capillarity, from top to bottom eliminating, by the same, the moisture. The wood, thus dried, the process of deterioration is slowed down. The amount of rods required is calculated based on the circumference of the column.
Each drilled hole must be plugged with wooden bushings at least 1/16 “larger than the diameter of the hole, and several sizes of bushings are available.
There is also smoke treatment that eliminates insects and plants. The characteristic of such a treatment is that the liquid introduced into the post, in contact with moisture, is transformed into a gas which disperses rapidly in the wood and, as a result, dries out the vegetal areas and eliminates any presence of insects.
Another widely used treatment technique in North America is a 30-inch pole-perimeter excavation and the application of a sodium fluoride-based preservative. This place enters the pole to dry. In order to prevent the treatment from dispersing into the soil, an impermeable membrane is wrapped around the treated portion of the pole.
Depending on the diagnosis, a treatment or set of treatments is then applied to the pole. One or a few identification plates (tag) are fixed to the treated pole; we can find the year of inspection, and the name of the treatment product applied.