Gumleaf skeletoniser

Gumleaf skeletoniser larvae can cause severe skin irritation to humans on contact.

The gumleaf skeletoniser (Uraba lugens) is a common pest of eucalypt trees. Periodic outbreaks completely defoliate trees, causing widespread damage. Initially, foliage on affected trees has a typical bronze appearance, as if the tree has been scorched by fire.

Outbreaks often occur during the winter, with most damage in late winter to early spring.

Scientific name

Uraba lugens

Description

  • Hairy larvae with yellow and brown markings and a 'hat' made up of head capsules that are shed after each moult.
  • Larvae are 5–20mm long.
  • Young larvae usually cluster on the leaf surface, while older larvae disperse and feed individually.

Similar species

Can be distinguished from other hairy caterpillars found on eucalypts by the:

  • skeleton-like appearance of the damage
  • 'hat' formed on the head of the caterpillars.

Distribution

  • Widespread across temperate, subtropical and tropical Australia.

Hosts

  • Narrow-leaved ironbark (Eucalyptus crebra)
  • River red gum (E. tereticornis)
  • Spotted gum (Corymbia citriodora ssp. variegata)
  • Western white gum (E. argophloia).

Damage

  • Larvae damage leaves a skeleton of leaf veins. Affected trees have a bronze, scorched appearance from a distance. Older larvae chew entire leaves.
  • Trees usually recover from damage over time, but repeated defoliation can cause tree death.
  • Larvae may move onto nearby trees, structures and buildings.

Monitoring and action

  • Control of caterpillars on trees in the landscape is not feasible.
  • Larvae are covered with urticating hairs which can cause severe skin irritation in humans. Caterpillars near houses may be sprayed with household insecticides and surface sprays to prevent entry.

Resources and research

  • Carnegie, A, Lawson, SA, Smith, T, Pegg, GS, Stone, C, and McDonald, J 2008, Healthy hardwoods: a field guide to pests, diseases and nutritional disorders in subtropical hardwoods, Forest and Wood Products Australia, Victoria.
  • Berndt, LA, and Allen, GR 2010, 'Biology and pest status of Uraba lugens Walker (Lepidoptera: Nolidae) in Australia and New Zealand', Australian Journal of Entomology, vol. 49 (3), pp. 268–277

Contact

General enquiries 13 25 23