1. Centre of Excellence for Invasion Biology, Department of Botany & Zoology, Stellenbosch University, Matieland 7602, Republic of South Africa;
2. Department of Ecology and Evolutionary Biology and Center for Embedded Networked Sensing, University of California, Los Angeles, California 90095-1606
3. Department of Botany, University of Wyoming, Laramie, Wyoming 82071
4. Warnell School of Forestry and Natural Resources, University of Georgia, Athens, Georgia 30602
5. Centre d’Ecologie Fonctionnelle et Evolutive, U.P.R. 5175-C.N.R.S., 34293 Montpellier, France and Missouri Botanical Garden, St. Louis, Missouri 63110
6. USDA Forest Service, Pacific Southwest Research Station, Riverside Fire Laboratory, Riverside, California 92507
7. Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria 0002, South Africa