Samples of tension wood and opposite wood were obtained from four species (Iyranthera sagotiana, Ocotea guyanensis, Virola michelii, Sextonia rubra) growing in the tropical rainforest of French Guiana. Dynamic mechanical analysis was performed in the longitudinal dimension with samples in the green "never dried" condition. Temperature and frequency of the tests were regulated to be similar to conditions experienced by the living tree. Tension wood from the species containing a Glayer was found to have higher damping characteristics than opposite wood from the same species whilst no difference was found between the wood types of the non G-layer species. The research thus far does not permit a solid conclusion but speculation into the possible origin of these differences is drawn from the nature of the G-layer matrix.