Damage to trees due to forestry operations and its pathological significance in temperate forests: a literature review

The damage caused to temperate forests by forestry operations is examined by a review of the scientific literature. A significant proportion of the remaining trees, especially in older stands, can be damaged during mechanized selective logging in forests, when operations are carried out in summer. Damage is most often caused during transport of timber. Most of the resulting wounds occur near the base of the tree and are up to 200 cm(2) in size. Damage to roots has negative effects on tree growth. Wounds on trees are attacked by fungi, causing stain and decay. In most tree species, the spread of wound decay is extensive and devalues several metres of the butt log. Wound closure is usually too slow to have any significant effect on the incidence of wound infections, but in several tree species it may restrict the spread of decay. The financial losses in wood value at the final harvest, due to previous logging damage, are reported to be significant. Strategies are discussed for controlling the damage and wound decay-in a forest, emphasizing silvicultural options for care of a stand during selective harvesting and wound treatment with appropriate dressings.