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Females of ormiine tachinids fly to their hosts' calling songs and deposit larvae on the host or nearby. Two species, Ormia ochracea (Bigo0 and O. depleta (Wiedemann), were reared for at least 8 generations, making them the first ormiines to be laboratory-propagated. Both were reared on natural hosts : Gryllus spp. field crickets (principally G. rubens) for O. ochracea, and Scapteriscus spp. mole crickets for O. depleta. Commercially reared Acheta domesticus tested as hosts were less satisfactory. Hosts were parasitized manually or by confinement with flies or planidia (infective larvae). Transparent, cylindrical, sleeved cages were designed to accommodate parasitized hosts and pupae and adults of O. ochracea. Cages were joined to allow O. ochracea to cycle through its stages with minimum handling and care. Parasitized hosts and pupae of O. depleta were held in containers of damp sand ; adults were held in cages developed for O. ochracea.Adults of both species were maintained on applesauce, sugar cubes, powdered milk, and water. The life cycle of O. ochracea was about 31 days and of O. depleta about 36 days, with the principal difference being the time required for planidia to complete development. In O. ochracea the adults emerged synchronously but in O. depleta males preceded females. In both species sex ratio was generally 1 : 1 and females lived slightly longer than males. O. depleta from our laboratory colony have been released for biological control of mole crickets.

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Invasion of south Florida wetlands by the Australian paperbark tree, Melaleuca quinquenervia (Cav.) S.T. Blake (melaleuca), has caused adverse economic and environmental impacts. The tree's biological attributes and favorable ambient biophysical conditions combine to complicate efforts to restore and maintain south Florida ecosystems. Management requires an integrated strategy that deploys multiple biological control agents to forestall reinvasion and to supplement other control methods, thereby lessening recruitment and regeneration after removal of existing trees. This biological control program began during 1997 when an Australian weevil, Oxyops vitiosa (Pascoe), was released. A second Australian insect, the melaleuca psyllid (Boreioglycaspis melaleucae Moore), first introduced during 2002, has also widely established. After inoculation of the psyllid in a field study, only 40% of seedlings survived herbivory treatments compared with 95% survival in controls. The resultant defoliation also reduced growth of the surviving seedlings. A weevil-induced decline at a site comprised mainly of coppicing stumps had slowed after a 70% reduction. Psyllids colonized the site, and 37% of the remaining coppices succumbed within 10 mo. The realized ecological host range of B. melaleucae was restricted to M. quinquenervia; 18 other nontarget plant species predicted to be suboptimal or nonhosts during laboratory host range testing were unaffected when interspersed with psyllid-infested melaleuca trees in a common garden study. Evaluations are ongoing, but B. melaleucae is clearly reducing seedling recruitment and stump regrowth without adversely impacting other plant species. Manifestation of impacts on mature trees will require more time, but initial indications suggest that the psyllid will be an effective supplement to the weevil.