Use of Harvesters With Debarking Head In Temperate Forests

Debarking helps to reduce the populations of sub-cortical pests (e.g. bark beetles) during heavy infestations, in order to prevent their spread. In the long term, debarking allows the nutrients contained in the bark to be returned to the soil. Compared with wood, the concentration of major elements contained in bark is up to 25 times higher. On moderately poor sites, this will make it possible to produce wood without having to amend or fertilize several times, and even without having to adapt the harvesting method. On very poor sites, this could limit the sometimes-restrictive harvesting recommendations for small trees. The study allowed to test the debarking technique using logging machines equipped with a specific kit based on the experience acquired in Germany. 4 test logging operations were carried out in the north-east quarter on France in 2021 and 2022 in fir and spruce stands. These trials made it possible to determine the main characteristics of this new technique: productivity, debarking rate, reliability of length measurement, machine settings, etc. Integrated in-stand debarking with a harvester is a technique that is worth developing. It requires only limited investment and does not compete with the use of bark in sawmills, since it will only be used on limited surfaces or in the event of health crisis.