Interspecific diversity of wind resistance strategies among temperate tree species: what is the role of radial variations of wood material properties in different tree organs?

PI : Jana Dlouha (UMR 1092 Laboratoire d’Etude des Ressources Forêts-Bois – LERFOB)

Collaboration :
T. Alméras (Laboratoire de Mécanique et Génie Civil, LMGC),
B. Moulia (Physique et Physiologie Intégratives de l’arbre Fruitier et Forestier, PIAF)
E. Nicollini (botAnique et bioinforMatique de l’Architecture des Plantes, AMAP
R. Schneider (Université Québec à Rimouski, UQAR)

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Context — Tree wind-resistance varies between species depending on the tree size, crown architecture and wood mechanical properties. When a tree is small/young, wind load is limited due to its size (short lever-arm) and low wind speed close to the soil. An adult/big tree may adopt different strategies to face the wind loads relying either on its body rigidity to tolerate the wind loads or on its trunk and branches deformability allowing to avoid the wind loads. Except for empirical ranking of tree species wind-resistance, little information is available about the occurrence and performance of these two groups of wind resistance strategies (tolerance/avoidance) among the tree species and tree compartments (trunk/branches).

Objectives — Perform a screening of a diversity of wind resistance strategies among temperate tree species and assess the contribution of mechanical properties of wood in trunk and branches to the establishment of a given strategy to tolerate/avoid wind loads during the tree growth.

Approaches — Tree morphology will be measured in order to assess the tree wind resistance on a selection of temperate species exhibiting, according to theoretical criteria, contrasting wind resistance strategies. Mechanical properties of wood will be assessed per annual ring in order to retrospectively understand how the rigidity of the tree body was build up in time.

Expected results and impacts — Better understanding of wind resistance strategies diversity among temperate species will be helpful for foresters searching for new species performing well in the context of climatic changes. Network joining the researchers, field experts, urban tree managers and public around questions of urban tree security will be activated. Better knowledge about the mechanical quality of wood from branches.