Weeds of National Significance (WoNS) is a list of the most problematic plant species in Australia as determined by the federal government. Initially a list of 20 taxa were listed and given a rank based on invasiveness, impacts, potential for spread, and socioeconomic and environmental values. An expanded list of 32 taxa was released in April 2012.
Weeds of National Significance Wikipedia
Note: The list of individual taxa is greater than the 32 WoNS.