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International audienceKey messageBeech is subjected to devaluating bark damage by logging operations. It is shown experimentally that damage in the upper part of the trunk entails much higher risk of wood discoloration and decay by fungi than damage in the lower part. Cellular defense mechanisms in xylem are elucidated.ContextDuring harvesting operations and more specifically processes of both felling and extraction, remaining trees suffer specific bark damages, leaving the exposed xylem vulnerable to subsequent discoloration and fungal decay. As a consequence, the future value of the produced timber is reduced.AimsThe objective of this study is to test for the consequences of artificial bark damage to the base vs. the upper parts of the trunk in terms of discoloration, fungal infection, wood decay, and wound closure.MethodsAn artificial basal “extraction wound” was inflicted along with an elongated “felling wound” at 5-m stem height in 40 beech trees (Fagus sylvatica L.) during either June or October. The trees were felled 3 years later and the impact of the wounds was evaluated with microscopic imaging and microbiological methods.ResultsThe compartmentalization observed in the basal extraction wounds was highly efficient, and rate and intensity of discoloration and susceptibility to decay were significantly lower than in wounds inflicted to the upper segments of the trunk. The latter displayed deeply penetrating discoloration and decay.ConclusionBark damage in the higher portions of the stem inflicted by felling is followed by much higher risk of wood discoloration and decay than damage at the base of the stem (extraction damage). Harvesting management has to be optimized in order to avoid felling damage in remaining neighboring trees particularly