History and management - Southern Africa and western Indian Ocean islands.

Abstract Parthenium weed (Parthenium hysterophorus) has been recorded in the Southern African countries of South Africa, Swaziland, Zimbabwe, Mozambique and most recently Botswana, and the western Indian Ocean islands of Madagascar, Mauritius including Rodrigues, as well as Réunion, Seychelles, Comoros, Mayotte and Salomon islands. This chapter outline the history of invasions, background, spread and management (using mechanical, chemical and biological control methods as well as containment strategies and growing competitive plant species) of parthenium weed in southern Africa and the Western Indian Ocean islands. Management of parthenium weed within Southern Africa and the western Indian Ocean islands remains a challenge, as it does for most developing countries, for a number of reasons. These include one or more of the following: (i) lack of inventory of invasive species and knowledge of their extent and impacts; (ii) lack of broad awareness of the impacts or potential impacts of invasive alien species such as parthenium weed; (iii) lack of value placed on conservation of biodiversity; (iv) lack of legislation on the management of invasive alien species; (v) lack of national long-term commitment and coordinated efforts to manage invasive species; (vi) limited resources for large-scale management programmes; and (vii) lack of expertise and/or facilities.