Debarking in temperate forests during harvesting using debarking heads (TAÉ)

Before the 1980s, manual debarking of logs was widespread in forests. The strong increase in labor costs and constant price of wood led to a transfer of debarking to factories just before processing. The reactivation of debarking in forest during harvesting is possible thanks to a technique already widely used for more than 35 years in tropical forests using debarking heads. Discover this technique in the follwing video.
Publié le 4/25/23

English version

©Plan Rapproché

English version

©Plan rapproché

The benefits of on-site debarking

  • Total weight reduction of logs during transport ;
  • Nutrient return to forest soil (concentrations in bark are up to 25 times higher than in wood). On moderately poor forest sites, this makes it possible to produce wood, without amendment or fertilization, or even without adaptation of the harvesting method ;
  • On very poor forest sites, this could limit harvesting prescriptions, which are sometimes quite restrictive, i.e. having to leave small trees and branches in forests ;
  • Avoid or reduce the propagation of infestations by subcortical insects (e.g. bark beetles).

Did you know?

Debarking prevents bark beetles from spreading.

Indeed, under the bark, you’ll find the larvae of bark beetles. Debarking trees and leaving bark exposed to light, cold or heat, leads to the death of larvae and nymphs of bark beetles. This is also the case for young white imagos, after metamorphosis, which are still under the bark.

Harverting head to debark logs

Debarking heads are used for more than 35 years in tropical forests. Adaptation of this technic for temperate forests have been done by german teams which was collaborators into the french projet, cofinanced by France Bois Forêt.

With the support of France Bois Forêt

This project, named TAE, aims to help practitioner to their appropriation of the debarking technique on the bases acquired in Germany, using harvesting machines equipped with a specific kit.

Harvesting tests since 2021

Tests were carried out on 4 sites in the northeast quarter of France in 2021 and 2022, in fir and spruce stands.

These tests made it possible to determine the main characteristics of this new technique: productivity, debarking rate, reliability of length measurement, machine adjustments, etc.