Granulate ambrosia beetle

This unwanted pest has been detected in 5 Auckland areas since 20 February 2019. Find out about the beetle and why we need you to report sightings.



The granulate ambrosia beetle is regarded as a serious pest overseas. It is known to damage a wide range of broadleaf trees, including horticultural species. It can also spread fungal diseases.

The beetle is native to tropical and subtropical East Asia. It has been found in many areas in the world, including Africa, the USA, Central America, Europe, some Pacific Islands, and most recently in Queensland, Australia.

It's the first time the beetle has been found in New Zealand, although evidence suggests it may have been in the country for at least 2 years.

Risk to New Zealand

Biosecurity New Zealand is assessing the potential risk from the beetle to New Zealand.

What we're doing 

We're working with local authorities to identify the extent of the spread, including inspecting known host trees and placing lured traps around the detection sites.

Download the granulate ambrosia beetle fact sheet [PDF, 427 KB]

What you can do

We need you to tell us if you think you see damage caused by the pest or the beetle itself.

A tell-tale sign is distinctive protrusions of frass (compacted sawdust) from bark that look like toothpicks. They are caused by the beetles pushing frass out of tunnels bored into the trees. Other symptoms include sap oozing from the tunnel entrances and branch dieback.

If you see the beetle or any sign of frass on trees:

  • take a photo
  • phone our pests and diseases hotline on 0800 80 99 66.

Images of the beetle and frass

tree trunk with worm-like sawdust protrusions
Sawdust strings protruding from the trunk of a tree. Image: with permission from Jiri Hulcr, University of Florida.
Top view of dark-brown beetle
Top view of an adult female ambrosia beetle. Image: © Lyle J. Buss, University of Florida.
Side view of a dark brown coloured beetle
Side view of an adult female ambrosia beetle. Image: © Lyle J. Buss, University of Florida.
Last reviewed:
Has this been useful? Give us your feedback