Tension wood and opposite wood in 21 tropical rain forest species. 1. Occurence and efficiency of G-layer

Bruno Clair (1, 2) , Julien Ruelle (1, 3) , Jacques Beauchêne (1) , Marie-Françoise Prévost (4) , Meriem Fournier (1)

1 ECOFOG - Ecologie des forêts de Guyane
2 LMGC - Laboratoire de Mécanique et Génie Civil
3 SBS-NAGOYA - School of Bio-agricultural Science
4 UMR AMAP - Botanique et Modélisation de l'Architecture des Plantes et des Végétations

Wood samples were taken from the upper and lower sides of 21 naturally tilted trees from 18 families of angiosperms in the tropical rain forest in French Guyana. The measurement of growth stresses ensured that the two samples were taken from wood tissues in a different mechanical state: highly tensile stressed wood on the upper side, called tension wood, and lower tensile stressed wood on the lower side, called opposite wood. Eight species had tension wood fibres with a distinct gelatinous layer (G-layer). The distribution of gelatinous fibres varied from species to species. One of the species, Casearia javitensis (Flacourtiaceae), showed a peculiar multilayered secondary wall in its reaction wood. Comparison between the stress level and the occurrence of the G-layer indicates that the G-layer is not a key factor in the production of high tensile stressed wood.

Keywords: wood anatomy; G-layer; gelatinous layer; French Guyana; tension wood; tropical rain forest

Domains: Other; Vegetal Biology

Bruno Clair, Julien Ruelle, Jacques Beauchêne, Marie-Françoise Prévost, Meriem Fournier. Tension wood and opposite wood in 21 tropical rain forest species. 1. Occurence and efficiency of G-layer. IAWA Journal, 2006, 27 (3), pp.329-338. ⟨10.1163/22941932-90000158⟩. ⟨hal-00112579⟩