Twelve taxa under exploration as bioenergy crops in Florida and the U.S. were evaluated for potential invasiveness using the Australian Weed Risk Assessment system (WRA) modified for separate assessment at the state and national scales. When tested across a range of geographies, this system correctly identifies invaders 90%, and non-invaders 70% of the time, on average. Predictions for Florida were the same as for the U.S. Arundo donax, Eucalyptus camaldulensis, Eucalyptus grandis, Jatropha curcas, Leucaena leucocephala, Pennisetum purpureum, and Ricinus communis were found to have a high probability of becoming invasive, while Miscanthus x giganteus, Saccharum arundinaceum, Saccharum officinarum, and the sweet variety of Sorghum bicolor have a low probability of becoming invasive. Eucalyptus amplifolia requires further evaluation before a prediction is possible. These results are consistent with reports on other tests of these taxa. Given the economic and ecological impacts of invasive species, including the carbon expended for mechanical and chemical control efforts, cultivation of taxa likely to become invasive should be avoided. (C) 2010 Elsevier Ltd. All rights reserved.