New Zealand's non-native flora - friends or foes?

New Zealand is acutely aware of the throats posed by invasive non-native plants. Nonnative species make up nearly ninety percent of the country's flora. Succulents, numbering over a hundred, constitute a relatively small proportion of the total. Most, if not all, of the country's non-native succulents are a consequence of introduction, escape from cultivation or careless disposal. Carpobrotus edulis and its hybrids pose a threat to native flora. The poisonous Cotyledon orbiculata poses a threat to livestock. These two species are controlled, to some extent, by restrictions on sale and distribution. Conservation measures, other than those applied to these species, are limited. The conservation authorities in New Zealand should be alert of the potential threats from some other succulent plants, especially at local level.