Myrtle rust made its way to Aotearoa New Zealand in 2017, being found first on Raoul Island in the Kermadec Islands, then a month later in Kerikeri on the mainland. Since then, the fungal disease has been found as far south as Christchurch.
Last month, Scion myrtle rust researcher Roanne Sutherland was visiting Aotea / Great Barrier Island when she discovered a self-seeded pōhutukawa seeding (Metrosideros excelsa) that was infected with myrtle rust, marking the first time that the pathogen has been found on the island.
While this is a sad finding it is not surprising, due to the nature of how myrtle rust spreads. Myrtle rust spores are microscopic and can become windborne, so can easily travel across large distances by wind. This may be how the disease made its way to Aotearoa four years ago.
The discovery has prompted a swift response from the Department of Conservation, Auckland Council and the Aotea / Great Barrier Local Board, who are working together to determine an appropriate response to manage the finding and liaise with the local community.
If you come across a suspected myrtle rust infection, be sure not to touch the plant or take samples, as you may inadvertently spread the disease. Instead:
- Take an image of the plant, including infected leaves, or other areas of the plant and a close-up of the spores.
- Submit your images to the iNaturalist website – experts will confirm the infection.