Tattered or holey leaves

Inset: close-up of the feeding beetles.

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.

Feeding on the young cigar leaf results in 'shot hole' type damage as the leaf unfurls. Inset: close-up of the feeding beetles.

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.

Cluster caterpillars and damage caused to leaf.

Cluster caterpillar

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. 

Inset: close-up of rolled leaf.

Banana skipper

Biosecurity Alert

Cause: Larvae of Erionota thrax feed on the leaf blade and strip and roll it to form a shelter in which the larva develops. In heavy infestations, the entire leaf lamina is destroyed, leaving only the midrib.

Biosecurity: This leaf pest has not been found in Australia or Torres Strait Islands but is well established in Papua New Guinea. It is widely distributed throughout China, India, South East Asia, Mauritius and Hawaii. Report all suspicious outbreaks to Biosecurity Queensland immediately (13 25 23).

Grasshopper

Cause: Feeding by grasshoppers Valanga spp.


Solution: The damage is mostly cosmetic as plants will rapidly compensate for any leaf loss. It is usually only a problem on young plants, especially on new plant crops. No treatment is required.

Wind

Cause: Strong winds tearing the leaf lamina.


Solution: Retaining existing vegetation or planting specific windbreak trees can reduce the damage caused by strong winds.