Review of factors that influence wood durability shows that although density varies depending on stem position, its role on decay resistance appears controversial. The role density plays in influencing the durability of three hardwoods from Ghana, namely Nauclea diderrichii (de Wild.) Merr., Nesogordonia papaverifera (A. Chev.) R. Capuron) and Corynanthe pachyceras Welw. is therefore investigated for the first time, especially for tropical species, south of the Sahara. The densities of these species average between 654-695, 655-692 and 713-816kgm3 respectively at 12% equilibrium moisture content (emc) for the inner and outer heartwoods (IHW and OHW respectively). That of the middle sapwood (MSW) of C. pachyceras (a Lesser-Utilized-Species (LUS)) that has been previously found durable and therefore employed in this study is 655-794kgm3. Extracted densities for all the three species are determined by correcting for the total extractive contents in each stem position. Total extractive contents for the heartwoods of N. diderrichii, N. papaverifera and C. pachyceras are 13.29-13.96, 10.18-10.65 and 11.03-14.19% respectively, while that of the MSW of C. pachyceras is 9.68%. These are determined using ethanol-toluene (1:2) according to ASTM: D1105-96 (Anon., 1996). The relationship between the densities (unextaicted and extracted) of IHW and OHW of the two traditional species (N. diderrichii and N. papaverifera) and their weight losses resulting from decay by Coriolus versicolor (Linnaeus) Quelet. (a white-rot decay fungus) is investigated. For C. pachyceras, the correlation is between IHW, OHW and MSW. Poor correlations are obtained; being R2 = 0.0095, 0.0103 and 0.1251 for N. diderrichii, N. papaverifera and C. pachyceras respectively. The study shows that while extractives play much role in wood durability, density alone has little influence on the decay resistance of the three tropical hardwoods against C. versicolor.

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