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Aim Many Australian Acacia species have been planted around the world, some are highly valued, some are invasive, and some are both highly valued and invasive. We review global efforts to minimize the risk and limit the impact of invasions in this widely used plant group.

1) The voting that took place at the nomenclatural session of the International Botanical Congress (IBC) in Vienna was illegal from the point of view of parliamentarian procedure and practical application. 2) Only one species type must be assigned to the genus Acacia; this would be decided through a new procedure that follows the established rules. 3) Taxonomically speaking, the former subgenera of the genus Acacia belong to at least three different lineages that resolve within the tribe Mimoseae; therefore, the current debate for assigning a type to the genus revolves around two of the three subgenera: Acacia (Acacia) and Acacia (Phyllodineae = Racosperma).

Aim? Many Australian Acacia species have been planted around the world, some are highly valued, some are invasive, and some are both highly valued and invasive. We review global efforts to minimize the risk and limit the impact of invasions in this widely used plant group. Location? Global. Methods? Using information from literature sources, knowledge and experience of the authors, and the responses from a questionnaire sent to experts around the world, we reviewed: (1) a generalized life cycle of Australian acacias and how to control each life stage, (2) different management approaches and (3) what is required to help limit or prevent invasions. Results? Relatively few Australian acacias have been introduced in large numbers, but all species with a long and extensive history of planting have become invasive somewhere. Australian acacias, as a group, have a high risk of becoming invasive and causing significant impacts as determined by existing assessment schemes. Moreover, in most situations, long-lived seed banks mean it is very difficult to control established infestations. Control has focused almost exclusively on widespread invaders, and eradication has rarely been attempted. Classical biological control is being used in South Africa with increasing success. Main conclusions? A greater emphasis on pro-active rather than reactive management is required given the difficulties managing established invasions of Australian acacias. Adverse effects of proposed new introductions can be minimized by conducting detailed risk assessments in advance, planning for on-going monitoring and management, and ensuring resources are in place for long-term mitigation. Benign alternatives (e.g. sterile hybrids) could be developed to replace existing utilized taxa. Eradication should be set as a management goal more often to reduce the invasion debt. Introducing classical biological control agents that have a successful track-record in South Africa to other regions and identifying new agents (notably vegetative feeders) can help mitigate existing widespread invasions. Trans-boundary sharing of information will assist efforts to limit future invasions, in particular, management strategies need to be better evaluated, monitored, published and publicised so that global best-practice procedures can be developed.

Nine methods of overcoming seed-coat dormancy of Racosperma auriculiforme (provenance KZNO) from Zaïre were investigated. Soaking seeds in concentrated sulphuric acid for 15 or 30 min and then rinsing for 15 min with tap water produced the best results for laboratory testing as well as operational application. Boiling water from which the heat source has been removed and in which the seeds are placed and soaked until the water is cool (12–24 h) is the most suitable and economical method for social forestry programs at the village level in Zaïre. Key words: Acacia, germination, Leguminosae, Racosperma, seed-coat dormancy, social forestry

En vue de planifier une strategie d'echantillonnage de la variabilite genetique de 3 especes d'arbres tropicaux, Racosperma auriculiforme, R mangium et Terminalia superba, les effets de 16 differents pH de tampons d'electrophorese, de 4 conditions de conservation des tissus et de 5 durees de conservation ont ete evalues pour l'electrophorese sur gel d'amidon de 18 enzymes. La resolution du nombre de loci et d'alleles presumes possibles ainsi que l'intensite de coloration des 18 enzymes etaient influencees de maniere sensible par le pH des systemes de tampons (.)

We report on an assay of direct transfer of DNA into calli and seeds of Racosperma (ex-Acacia) mangium, using a bioballistic method. We observed transient expression of the GUS gene in the treated tissues Descreve-se um experimento de introdução de DNA em calos e sementes de Racosperma (ex-Acacia) mangium, utilizando um método biobalístico. A expressão do gene marcador GUS foi observada nos dois tipos de tecidos