Several Malagasy Dalbergia and Diospyros species are highly valued, especially in the furniture industry due to their desirable wood properties. However, there remains a lack of understanding regarding the wood technological properties of many species within these genera, hindering their effective utilization.

This study aimed to adress this gap by assessing the wood density of 38 Dalbergia and 29 Diospyros species, their radial wood density variation, and the in uence of climate and tree size. Wood density measurements were conducted on 297 wood cores using X-ray computed tomography. One-way analysis of variance was used to evaluate between-genus, between-species, and between-trees density variations. To compare the radial density pro le of cores of different length, each analyzed core was divided into 10 segments of equal length. For species that show signi cant differences in mean density along the segments, the radial density trend was evaluated through correlation tests between the average density of each segment and its distance from the pith. Correlation test was also conducted to evaluate the relationship between tree diameter, climatic data, and density. Diospyros genus (1.070 ± 0.165 g•cm -3 ) have signi cantly denser heartwood compared to Dalbergia (0.961 ± 0.142 g•cm -3 ). Furthermore, eleven groups of Dalbergia and seven groups of Diospyros, each with signi cantly different heartwood density value ranges, were identi ed. While the radial wood density pro le varied among species, a decreasing trend was observed in most analyzed species. Wood density increases with rising temperature and decreasing precipitation at the tree's growth site. Tree diameter does not in uence the wood density.