Insect Damage to Plantation‐grown Eucalypts in North Coastal New South Wales, With Particular Reference to Christmas Beetles (Coleoptera: Scarabaeidae)

The Christmas beetles Anoplognathus chloropyrus and A. porosus feed on the leaves of eucalypts, particularly E. grandis , in plantations established for wood pulp production. A. chloropyrus is highly gregarious, causes more damage than does A. porosus , and tends to be present in high numbers in alternate years. Because of the timing of the insects’ life cycles, and their feeding preferences, defoliation levels below about 50 % are unlikely to reduce the rate of tree growth. Severe defoliation is limited to young trees planted on old grasslands which provide a favoured breeding place for the insects. Possible methods of minimizing damage by A. chloropyrus are discussed.