Shoot flies, gall midges, and shoot and rhizome mining moths associated with common reed in Europe and their potential for biological control

Common reed, Phragmites australis (Cav.) Trin. ex Steudel has recently become an invasive in freshwater and brackish wetlands in North America. Particularly along the Atlantic Coast, P. australis is forming large monospecific stands that replace native wet-land vegetation and provide poor habitat for native biota. The reasons for the rapid spread of P. australis are unclear. Although fossil rhizomes of the plant were recently discovered in North America, the current population explosion is often attributed to accidental intro-ductions of more competitive genotypes. Regardless of its status as introduced or indige-nous, invasions of P. australis are a threat to biodiversity in natural wetlands and have resulted in intensive control attempts. Chemical, mechanical, and physical control or com-binations of these methods can suppress P. australis in the short-term, however treatments need to be repeated every 3-5 yrs and may have undesirable effects on non-target species. Twenty eight insect herbivore species feed on P. australis in North America. However, only 5 of these are native to North America whereas 13 species have recently been intro-duced accidentally. In contrast to the scarcity of native herbivores associated with P. aus