Tattered or holey leaves
Greyback cane beetle
Cause: Feeding by adults of Dermolepida albohirtum. Damage is seldom severe, but extensive feeding on older leaves of bunched plants can lead to sunburnt fruit.
Solution: There are no recommended foliar chemical treatments as these will interfere with biological control and will result in serious mite infestation. This will be more damaging and costly than greyback cane beetle damage.
Swarming leaf beetles
Cause: Leaf feeding of large numbers of adult Monolepta australis or Rhyparida spp. beetles. They swarm in spring and summer.
Solution: Damage is sporadic and no specific treatment is required.
Cause: Young larvae of Spodoptera litura feeding in groups on either the top or bottom of leaves, leaving the opposite side intact. Large larvae are solitary.
Solution: Damage is sporadic and most often concentrated on the tender leaves of plant crops. Fruit damage is usually restricted to a few isolated bunches and seldom requires specific treatment.