Using specimens from the CIRAD Kourou wood collection to build a database of properties

Abstract

A Xylarium, like the one in Kourou in French Guiana, is a unique collection of wood specimens assembled over many years that represents high interspecific diversity. In addition to the standard use of such collections for systematic anatomy, a technological database can be created using supplementary specimens taken from the same tree as the reference specimens. Physical, mechanical and durability tests were performed on wood planks measuring 10 × 60 × 100 mm3 (L is the longest direction, width and thickness are not always perfectly radial or tangential, just transverse) representing 445 woody species belonging to 63 families found in French Guiana. Wood densities ranged from 250 to 1,300 kg/m3, with an average of 786 kg/m3. The other properties also covered a wide range of values, as did the longitudinal modulus of elasticity (ranging from 0.6 to 37 GPa), as samples from lianas and palm stipes from very stiff woods were also tested. The correlations between the different parameters measured on the 445 species tested allowed us to identify some relationships between wood properties, e.g.: (i) light colored woods are less prone to shrinkage, but more prone to rot (the opposite is true for red woods); (ii) woods with a low damping coefficient are generally darker, redder, denser, and more resistant to rot. This database cannot be used to characterize a particular species as only one specimen is available for each species, but it can be used to study the relationships between properties and easily measured descriptors related to wood structure (e.g. density, modulus) or wood chemistry (e.g. color, durability).  Finally, this database provides the foundation for future bigger databases including many more specimens of each species that will be useful to search for particular properties in certain families or genera, for example, high natural durability despite rather low wood density, or low damping along with a high specific modulus.