In Hawaii and Tahiti the invasive tree Miconia calvescens (miconia) is referred to as the ‘purple plague’ and ‘green cancer’ because of the damage it inflicts on tropical rainforests in these countries – it has replaced vast areas of natural forest, resulting in landslides, erosion, diminished watershed functions of the forest and endangering a great number of endemic species.
Miconia has large attractive leaves (pictured) with purple undersides and because of this, was once a popular garden species in Australia. It was sold by several nurseries in Queensland and New South Wales during the 1970s and 1980s, before its invasive potential was understood. Mature miconia plants produce huge quantities of seeds that are readily spread by a large range of birds that live in our tropical rainforests. There are now 49 known infestations of miconia in Australia, all of them situated near Cairns and all of them subject to eradication.
Susie Hester and Oscar Cacho are part of a team of researchers who used computer models to determine the time and costs required to eradicate miconia infestations. Susie presented this research at the 2009 International Miconia Conference on Maui, Hawaii, using funding from the Australian Academy of Technological Sciences and Engineering, International Science Linkages – Science Academies Programme. The approach developed by Susie and Oscar has received very positive reviews and is being extended and applied to other invasive species.