ALERT: Myrtle Rust going strong
TTW Protecting what we value
Myrtle Rust hit our shores in 2017 spreading quickly to the predictable areas along the west coast of the North Island and attracting plenty of media attention. Since then there appears to be some radio silence about the disease, however this is not matched by a slowing down of the disease spread across the country. In fact we hear from whānau regularly about new incursions in areas thought to be rust free and on species thought to be resistant. We are asking you, our whānau, to check your local myrtle plants this summer and to help us track the spread of the fungal disease which is likely to be more active during the warmer weather. While it is most often spread by wind, it can be moved by people who brush up against it and carry it to new regions.
This is why it is important to thoroughly clean your clothes, shoes and equipment when you are in the ngāhere or near myrtle plants (i.e. pohutukawa, rata, manuka, kanuka, ramarama, swamp maire).
What are you looking for?
Myrtle rust as an early infection looks like a bright yellow powdery spots (eruptions) on the underside of the leaf. A mature infection will have the same bright yellow powdery spots (eruptions) on both sides of the leaf. Older lesions might look like brown/grey rust pustules, or grey ‘fuzzy’ spore growth on the undersides of leaves. In addition some leaves may become buckled or twisted and die off. Images of the disease can be found here and a guide to identifying the disease is here.
What do you do if you spot it (or think you have)?
If you think you see the symptoms of myrtle rust don’t touch it. If you have a camera or mobile phone, take clear photos, including the whole plant, the whole affected leaf, and a close-up of the spores or affected area of the plant, and submit it to the iNaturalist website via the Myrtle rust reporter where experts can check to confirm whether your identification is correct OR send it to us with details of where you found it and when, and we will submit on your behalf. Capturing this information through iNaturalist means it will be available to agencies and scientists in future to analyse the rate of spread and observed impacts. Watch this video for more information.
Further information and online learning modules about the disease can be found at Resources » Myrtle Rust
In 2021 we will roll out a new set of Myrtle Rust related projects including refresher courses on myrtle rust surveillance and seed conservation. We will also be working with our whanaunga Alby Marsh to look at hapū based solutions to myrtle rust, as part of our commitment to creating or finding indigenous solutions for a better planet. Let us know if you want to participate in those events or keep an eye on our social media accounts for further details.
The following information was sourced from the Myrtle Rust website. For more information about the disease, as well as additional resources, go to www.myrtlerust.org.nz.
Other actions you can take to reduce the risk of myrtle rust spread:
Arrive clean, leave clean
The forest you visit could be infected with myrtle rust without you knowing it. Before entering such areas for work or recreation, you should minimise the risk of spreading the rust by ensuring your equipment, clothing, and tools arrive clean and leave the area clean.
Buy healthy plants and prune in cool weather
Make sure myrtle plants bought for your garden are free from the symptoms of myrtle rust. Inspect the leaves and stems of plants before you buy them, and avoid buying plants that have signs of disease.
We recommend avoiding heavy pruning during warm weather as this will encourage susceptible new growth. Instead, prune myrtles only in late autumn and early winter to avoid encouraging new growth during warm weather when myrtle rust spores are more likely to form.
Monitor your plants
We recommend regular monitoring of myrtle plants for any sign of myrtle rust, particularly new, young growth, shoots, and seedlings.
Thank you to www.myrtlerust.org.nz for the resources.
This is what the infection looks like as an untreated infection in an urban environment. Photo credits to Cheri Van Schravendijk-Goodman.