BIOLOGICAL-CONTROL OF WEEDS

Classical biological control, i.e. the introduction and release of exo tic insects, mites, or pathogens to give permanent control, is the pre dominant method in weed biocontrol. Inundative releases of predators a nd integrated pest management are less widely used. The United States, Australia, South Africa, Canada, and New Zealand use biocontrol the m ost. Weeds in natural ecosystems are increasingly becoming targets for biocontrol. Discussion continues on agent selection, but host-specifi city testing is well developed and reliable. Post-release evaluation o f impact is increasing, both on the target weed and on non-target plan ts. Control of aquatic weeds has been a notable success. Alien plant p roblems are increasing worldwide, and biocontrol offers the only safe, economic, and environmentally sustainable solution.