Invasive plants: approaches and predictions

Successful management of invasive weeds will require active attempts to pre vent new introductions, vigilant detection of nascent populations and persi stent efforts to eradicate the worst invaders. To achieve these objectives, invasion ecology offers five groups of complementary approaches. (i) Stoch astic approaches allow probabilistic predictions about potential invaders b ased on initial population size, residence time and number of introduction attempts. (ii) Empirical taxon-specific approaches are based on previously documented invasions of particular taxa. (iii) Evaluations of the biologica l characters of non-invasive taxa and successful invaders give rise either to general or to habitat-specific screening procedures. (iv) Evaluation of environmental compatibility helps to predict whether a particular plant tax on can invade specific habitats. (v) Experimental approaches attempt to tea se apart intrinsic and extrinsic factors underlying invasion success. An em erging theory of plant invasiveness based on biological characters has resu lted in several rather robust predictions which are presented in this paper .