Summary Since the mid-1960s, 28 insecticide sprays or dusts, five fumigants (aluminium phosphide, dazomet, methyl bromide, naphthalene and p-dichlorobenzene) and one microbial insecticide (Bacillus thuringiensis) have been used, mostly in small quantities, by Australian forest services for control of indigenous and accidentally introduced insect pests in native forests, eucalypt or pine plantations, forest nurseries, and wooden structures. All of the applied insecticides have been officially registered for agricultural purposes (which include forestry applications) in each State/Territory under the provisions of a specific Act of Parliament. Until July 1989, the registration of insecticides by State/Territory authorities was subject to stringent evaluation and clearance by the Technical Committee on Agricultural Chemicals, a central authority responsible to the Co-ordinating Committee on Agricultural Chemicals, and through it to the Australian Agricultural Council. Since then, evaluation and clearance for registration has been the function of the Australian Agricultural and Veterinary Chemicals Council with direct responsibility to the Federal Minister for Primary Industries and Energy. This Council, established under the Commonwealth Agricultural and Veterinary Chemicals Act (1988), aims to ensure uniformity of assessment and registration of insecticides throughout Australia. In each State, special permits may be issued to allow insecticides to be used for purposes not covered by the registered product label or unregistered insecticides to be used in research trials. Additional legislation in the form of Acts of State Parliament, and Associated Regulations, governs the distribution, application and safe handling of registered insecticides. Most forest authorities now record insecticide purchases and consumption, and all have issued detailed instructions to their staff on spray preparation, storage, disposal, safe transport, spillage, accidental poisoning, loss or theft. The most extensive use of insecticides has been against the indigenous Spur-legged Stick Insect, Didymuria violescens (Phasmatidae), in Victorian ash-type eucalypt forests by aerial spraying with malathion, and for eradication of the accidentally introduced West Indian Drywood Termite, Cryptotermes brevis (Kalotermitidae), in south-eastern Queensland and New South Wales, by fumigating entire buildings and furniture with methyl bromide. In Tasmania, extensive aerial applications of synthetic pyrethroids have been carried out by APPM Forest Products to safeguard young plantations of principally Eucalyptus nitens (Shining Gum) from defoliation by the Tasmanian Eucalyptus Leaf Beetle, Chrysophtharta bimaculata. Outbreaks of all these pests cause serious economic damage when left unchecked. A sustained media campaign critical of pesticide usage in Australia has induced a much greater public awareness of the likely health risks posed by insecticides. Forest services are now committed to limit the use of insecticides and to promote biological and silvicultural techniques as alternative controls. Using insect resistant genotypes in eucalypt plantation programs is also expected to relieve insect pest problems in the future. However, insecticide applications are likely to remain front-line options for eradicating exotic insect pests of high destructive potential and for controlling large outbreaks of indigenous pests in commercial eucalypt plantations or in forest nurseries.
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