The Biology, Ecology, Distribution and Management of Two Globally Invasive Weeds: Calotropis procera (Calotrope) and Calotropis gigantea (Giant Calotrope)

Abstract

Calotropis procera and C. gigantea are emerging as globally invasive plants that can significantly alter ecosystems in areas where they have escaped from attended cultivation. Without effective management, these species can form dense monospecific stands, resulting in severe economic, environmental and social impacts. Current control measures for these species are often limited in effectiveness, especially when applied as single‐use approaches. To address this issue, this review synthesises key biological and ecological traits, current and potential invasion dynamics and management options available for C. procera and C. gigantea . Although more detailed investigation is required in some areas, it appears that an integrated approach is emerging as a possible option. Such an approach should consider (i) early detection and preventative strategies, including creating and maintaining competitive pastures and reducing soil disturbance, (ii) biological control, with the potential development and release of host‐specific insects and plant pathogens, (iii) chemical control with diverse modes of action, (iv) physical control including manual removal of all plant propagules from the soil and (v) ecological burn programs to remove the aboveground biomass followed by chemical or physical interventions. It is anticipated that the implementation of these strategies is likely to significantly mitigate the impacts posed by established C. procera and C. gigantea stands, while also addressing and removing newly emerging individuals before they develop robust populations.