How do you spot a (tree) killer?

There are five ways to identify the deadly myrtle rust this summer. Do you know them?

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Myrtle rust (Austropuccinia psidii) has been found in Northland, Waikato, Te Puke, and Taranaki. It’s a fungus that can destroy our native and taonga trees and plants such as pōhutukawa, rātā, kānuka, ramarama and mānuka.

The fungus attacks plants belonging to the Myrtaceae family, also known as the myrtle family. It is found in many parts of the world including New Caledonia and all along Australia’s east coast.

Myrtle rust spores are microscopic and can easily spread across large distances by wind, or via insects, birds, people, or machinery. It absolutely thrives in spring, making it much easier to spot.

Look out for signs of myrtle rust. Symptoms to be aware of on myrtle plants are:

  • bright yellow powdery eruptions appearing on the underside of the leaf (young infection)
  • bright yellow powdery eruptions on both sides of the leaf (mature infection)
  • brown/grey rust pustules (older spores) on older lesions
  • grey, ‘fuzzy’ spore growth on undersides of leaves
  • some leaves may become buckled or twisted and die off

If you think you see the symptoms of myrtle rust:

  • don’t touch it or try to collect samples as this may increase the spread of the disease
  • call the MPI Exotic Pest and Disease Hotline immediately on 0800 80 99 66
  • if you are able, take clear photos, including the whole plant, the whole affected leaf, and a close-up of the spores or affected area of the plant

Remember, do not touch or disturb the plant. Take a photo and call MPI immediately on 0800 80 99 66. We can all help to control its spread. For more information, visit www.mpi.govt.nz/myrtlerust