Gumleaf skeletoniser

Gumleaf skeletoniser (Uraba lugens) is an Australian insect that causes damage mainly to gum (Eucalyptus) trees by eating the foliage. The insect has become established in the Auckland region and is now spreading to other parts of the country. Click here to see current distribution.

About the insect

The young caterpillars "skeletonise" gum leaves by eating the green parts of the leaves, avoiding the veins. Older larvae are capable of eating whole leaves, thus increasing damage. Repeated defoliation can slow tree growth or, in severe cases, kill individual trees.

Gumleaf skeletoniser caterpillars have hairs that can cause itching or a rash on skin contact. People handling affected plants should wear protective clothing.

For more information on the insect click here.

What damage is it likely to do?

Gumleaf skeletoniser has the potential to disperse throughout all areas of New Zealand where eucalypts will grow. The insect prefers moderate climatic conditions that are neither too dry nor too wet.

Gumleaf skeletoniser caterpillars have an appetite for many of the eucalypt species growing in New Zealand. Some of the eucalypt to be attacked most severely are E.nitens, E.globulus, E.nicholii, E.obliqua and E.cinerea. It was been found to live successfully on other related Australian trees, such as Lophostemon. In New Zealand, the insect has also been detected on silver birch (Betula pendula) and can damage some oak species, copper beech and plum.

Gumleaf skeletoniser is not generally attracted to New Zealand native plants.

For more information about likely impact of the pest click here.

Protecting your trees

Forest growers can monitor for the presence of gumleaf skeletoniser using pheremone traps or visual surveys. Signs of chewing damage will become visible when the larvae are feeding, between the months of January-March and May-September.

In the event that gumleaf skeletoniser is found on your trees, chemical control options are available. For an information sheet on monitoring and control - Ensis Forest Biosecurity and Protection 07 343 5777.

Ensis research programme

Ensis has been contracted by Biosecurity New Zealand to develop tools and information to assist forest managers, landowner and regional authourities faced with on-going pest management. As part of this ongoing research programme, Ensis has developed control measures to slow gumleaf skeletoniser spread, and investigated biology, defoliation impacts, biological control and spray effectiveness.