Seed and phyllode variation in blackwood was studied intensively by Farrell & Ashton (1978). Phyllodes tend to be smaller and more symmetric in the drier-inland areas. The largest phyllodes were found in south-west Victoria (probably extending into the far southeast of South Australia). Some differences in seed size were found but were not clearly related to environmental conditions. <P>The role of fire was important in the ecology of the species which regenerates freely from soil-stored seed after fire or when the soil is exposed or disturbed. Some evidence was found that soil-stored seed is viable for at least 50 years. <P>The pods from northern populations (i.e. Qld) tend to be smaller and more convoluted. The late development of the phyllode of blackwood after the juvenile pinnate leaf phase is well known. Seedling populations from 17 sites but not including a South Australian sample were tested under uniform conditions. The onset of phyllode development after the juvenile phase ranged from 2 months to 7 months. Significant differences between populations were correlated with the wide range of climatic variables. Phyllodes were produced more rapidly on populations from drier sites, and the relative size of the bipinnate leaf was related to the site rainfall.<P>The cell structure and morphology of the phyllode of <I>A. melanoxylon</I> was studied by Boke (1940). The finer details are not relevant here. He concluded that <I>Acacia</I> phyllodes are homologous with the petiole-rachis of a pinnate leaf.<P><I>A. melanoxylon</I> has been popular as an ornamental timber. The heartwood is attractively coloured, strong, close-grained, dresses well and is widely used for furniture and cabinet work. However trunks are often limited in size and supply as almost all the larger trees have now been removed. It also makes a good fuel.<P>Three mistletoes have been recorded on <I>A. melanoxylon</I>. There is a single record of <I>Lysiana exocarpi</I> and many more, but almost equal, numbers of <I>Amyema preissii</I>, wire-leaved mistletoe and <I>Amyema pendulum</I>, drooping mistletoe, more often found on <I>Eucalyptus</I>.<P><I>A. melanoxylon</I> has been very successful in South Africa, Ross (1975) where it is now established in several provinces. Like <I>A. cyclops</I> and <I>A. saligna</I> it is also invading and displacing indigenous vegetation. It is locally established in southern Europe and occasionally established in California. <I>A. melanoxylon</I> is now naturalised in New Zealand, Webb et al. (1988).<P><I>A. melanoxylon</I> is included in Boland et al. (1984) 'Forest Trees of Australia' where a description, illustration and a map are given.<P>Two trees of <I>A. melanoxylon</I> in cultivation in the Waite Arboretum lived for 30 and 32 years.