Diagram showing several phases of Acacia dealbata invasion in relation to the different hypotheses for invasiveness and for transition from one phase to another. The discontinuous line is a schematic representation of major barriers to the spread of introduced plants. PPH, propagule pressure hypothesis; FRH, fluctuating resource hypothesis; DH, disturbance hypothesis; ERH, enemy release hypothesis; EICA, evolution of increased competitive ability hypothesis; NW, novel weapons hypothesis; FI, faunal interaction; VT, vegetative traits. Adapted from Sharma et al. (2005a).