Fig. 9From: Environmental factors and wood qualities of African blackwood, Dalbergia melanoxylon, in Tanzanian Miombo natural forestRelationship between the evaluated appearance grade and stress-wave velocity (Vs) of ABW. Each correlation coefficient of the site was, respectively, showed as follows; Kikole: r = 0.2622, Nainokwe: r = 0.0523, Nanjirinji: r = − 0.1128Back to article page