Coconut lumber for wood decks (Cocos nucifera L.): decay resistance against Basidiomycetes fungi
B Jourez, C Verheyen, J Van Acker
Since a couple of years, manufactured products of coconut wood for outdoor uses like wood decks have been proposed on the European market. These are presented as an alternative for traditional tropical timbers. In the past, coconut wood was neglected and burned for sanitary reasons and lack of interest at industrial scale. Plantation coconut trees at end of production of copra constitute a renewable resource with high added value. In order to convince the markets, natural durability for outdoor use, without preservative treatment, against wood destroying fungi characteristic of northern temperate regions is a major property that has to be checked. Natural durability of coconut lumber was tested in the laboratory according to the European standard EN 15083-1 against brown (Coniophora puteana) and white (Coriolus versicolor) rot decay basidiomycetes fungi. Beech wood specimens were used as virulence controls. Mass losses were determined after 16 weeks exposure. The results showed that tested coconut wood is very resistant to the brown rot fungus Coniophora puteana and resistant to the white rot fungus Coriolus versicolor. Mass loss and density of tested samples with C. versicolor are inversely related. In addition, the density shows a large variability in the test sample, more than 500 kg / m³. These results confirm that after a selection on density criteria, the natural durability of Coconut lumber is sufficient for outdoor application in use class 3 (based on European standard EN 335 and in line with EN 460).