INTEGRATED PEST-MANAGEMENT OF THE TASMANIAN EUCALYPTUS LEAF BEETLE, CHRYSOPHTHARTA-BIMACULATA (OLIVIER) (COLEOPTERA, CHRYSOMELIDAE)

Chrysophtharta bimaculata is the most economically important pest of eucalypt forests in Tasmania causing severe growth losses in plantations and seeded stands of the major commercial eucalypt species. An integrated pest management (IPM) strategy has been developed which allows peak activity of the natural enemies of C. bimaculata and monitors pest egg and larval populations before significant defoliation takes place. The relationship between beetle population level and degree of defoliation is quantified by regression models which are used to identify potentially damaging populations and the need for additional artificial control measures. The biotic insecticide, Bacillus thuringiensis var. tenebrionis was successfully tested against C. bimaculata larvae, and the use of B. thuringiensis and the synthetic pyrethroid, cypermethrin, in the IPM strategy is discussed.