Competition improves quality-related external stem characteristics of Fagus sylvatica

Accurate information on the timber quality of hardwoods is often lacking, in particular for standing trees. In situ measurements of timber quality have the potential to improve the economic yield of a stand and may contribute to the optimal timing of a harvest and, in general, to improving forest management. Here, we used terrestrial laser scanning (TLS) to assess external timber quality metrics nondestructively. We investigated how competition intensity affected the metrics of 118 European beech (Fagus sylvatica L.) trees. We found that two newly developed TLS-based measures of external stem characteristics (number of bark anomalies per metre and stem non-circularity) were affected by competition intensity, suggesting that regulating competition levels may improve timber quality. Our study confirms empirical findings indicating a positive relationship between competition intensity and timber quality of European beech and offers a new methodology to assess external timber quality measures in the field objectively and nondestructively. Key words: bark anomalies, competition index, European beech, terrestrial laser scanning, timber quality. On manque souvent d'information precise sur la qualite du bois des feuillus, particulierement dans le cas des arbres sur pied. L'evaluation in situ de la qualite du bois pourrait ameliorer le rendement economique d'un peuplement, contribuer a determiner le moment optimal de la recolte et, de facon generale, ameliorer l'amenagement forestier. Nous avons utilise un scanneur laser terrestre (SLT) pour evaluer de facon non destructive les mesures externes de la qualite du bois. Nous avons etudie de quelle facon l'intensite de la competition a affecte les metriques de 118 hetres communs (Fagus sylvatica L.). Nous avons trouve que deux mesures recemment developpees basees sur le SLT (nombre d'anomalies de l'ecorce par metre et excentricite du tronc) sont influencees par l'intensite de la competition, ce qui indique que le controle du niveau de competition pourrait ameliorer la qualite du bois. Notre etude confirme des resultats empiriques selon lesquels il y a une relation positive entre l'intensite de la competition et la qualite du bois du hetre commun et offre une nouvelle methode pour evaluer objectivement et de facon non destructive les mesures externes de la qualite du bois sur le terrain. [Traduit par la Redaction] Mots-cles: anomalies de l'ecorce, indice de competition, hetre commun, scanneur laser terrestre, qualite du bois.
1. Introduction The conversion of pure forest stands to mixed stands is a major objective of forest management in several countries around the world (Food and Agriculture Organization of the [...]