Biological Control Agent Gallery

Released in 1997, the melaleuca weevil was the first biological control agent released by government agencies.The larvae are usually gooey from plant toxins that are ingested with leaf tissue. The larvae secrete these toxins as their own defense against predators.Like an overfed goldfish, weevil larvae often carry attached feces. These are called fecal coils.Larvae graze on the leaf tissue, leaving the waxy cuticle as evidence of their presence.This photograph shows both a larva and an adult, as well as damage from each. While larvae graze the living tissue from the leaf, adults chew oval-shaped holes in leaves.This branch shows damage from both adults and larvae. Adult weevils prefer new leaves, but will eat mature leaves. Larvae eat only new leaves.The melaleuca psyllid (Boreioglycaspis melaleucae) was released in 2002, and early results indicate that it is very successful.Psyllid nymphs produce waxy filaments that grow into a mass of flocculence that may function as protection from predators.Psyllid nymphs close to being adults.What we like to see when we turn leaves over--copulating psyllids. With twelve pairs (and three individual adults) on this leaf alone, imagine how many are on the entire tree!The newest tool to manage melaleuca populations is the melaleuca bud-gall fly (Fergosonina turneri). It is expected to be release near the end of 2004.Still in the quarantine stage, the stem-gall fly (Lophodiplosis trifada) should be the fourth biocontrol to be released on melaleuca.