ABSTRACT
As mentioned earlier, the heartwood of some species contains a potential array of chemicals that render the wood resistant to various agents of deterioration (Hillis 1962; Scheer and Cowling 1966; Taylor et al. 2002). e use of naturally durable woods is attractive from a public perception perspective, but it is important to remember that the compounds that provide this protection are still potent antimicrobials. It is also important to note that natural durability varies by position in the tree and between individual trees. e most durable heartwood is found in the base of the tree at the heartwood-sapwood interface. Durability declines inward toward the pith and upward in a given growth ring. ere is also evidence that natural durability declines in second-growth trees of some species, notably teak and redwood. Naturally durable wood from temperate climate species tends to perform best in non-soil contact applications. Many tropical species also perform well in soil contact, but care should be taken to ensure that these materials originate from sustainably managed forests.
