Needs for wood durability research on planted tree species in the tropics
K Yamamoto, T Toma, Ngo Duc Hiep, Nguyen Trong Nhan
The area of forest plantation has been expanding especially in tropical Asia since 1990’s. Most of them are developed for pulp and paper industries and planted with fast growing trees. It is expected that wood from those fast growing trees are also used for value added products such as sawn timber. In order to promote the utilization of fast wood as the resource of value added products, natural durability was examined by an accelerated decay test according to JIS Z2101 in Acacia species, Melaleuca species, and Tectona grandis from the sapwood to the heartwood. Weight losses of the examined heartwood indicated that A. auriculiformis, hybrid Acacia and T, grandis were classified into moderately durable, A. mangium was slightly durable, and both of Melaleuca species were non-durable. There were no difference found between planted and natural grown teak (T. grandis). All of sapwood examined was not durable. The proportion of heartwood in the stem is considered to be an important factor in plantation trees when these trees are used for value added products.