Important update on myrtle rust – 19 May

19/05/2017

Unfortunately we have received notification of further spread of myrtle rust. Please read the below for information on the latest situation, plus some important advice to those of you planning planting events, and for nurseries.

The Project Crimson Trust is seriously concerned for the impact of myrtle rust on our Metrosideros species; there’s no way of predicting how our native plants will cope with this fungal disease. We are asking for your help as New Zealand faces a major biosecurity threat to native plants with the discovery of myrtle rust. The below information is particularly important to anyone who might be either growing plants or planning planting days.

2 further properties in Taranaki have been confirmed positive with myrtle rust infection today (19 May 2017)

Both are plant businesses – one a further nursery in Waitara and the other a garden centre in downtown New Plymouth.

This brings the total number of known affected properties to 5 – a nursery and adjoining property in Kerikeri, 2 plant nurseries in Waitara and a garden centre in New Plymouth.

The new finds are disappointing but not unexpected. The Ministry of Primary Industries (MPI) expects to continue to find new locations of infection given the most likely scenario is that the fungal spores entered New Zealand from Australia during a major wind event.

All infected properties are Restricted Places, meaning there are restrictions on the movement of plants or other risk materials off the sites. Locations are being treated with fungicide, risk plants are being safely destroyed, and surveillance is underway in the areas surrounding the properties for signs of the disease.

There are 2 main reasons why the rust is being found in plant nurseries. Growing conditions there are ideal for the fungus with many vulnerable young plants in sheltered, warm and damp environments. In addition, there has been a large amount of communication with the nursery industry and growers have been particularly vigilant in checking their plants.

Myrtle rust impacts on Community Groups

Myrtle rust can have serious consequences for various species of plants in the myrtle family, including New Zealand native plants such as: pōhutukawa, ramarama, rata, rōhutu, mānuka, swamp maire, kānuka.  Introduced plants including, feijoa, eucalypts and bottle brushes are also susceptible to myrtle rust

DOC is working closely with MPI trying to restrict the spread of the disease. DOC staff are actively looking out for potentially infected plants in the wild. The impact on native forests will be noticeable if myrtle rust becomes established.

DOC began seed collection of potentially affected species some years ago and the urgency to get full representation of all Myrtaceous native species is imperative.

The THREAT

The disease could be on any plants from an infected area taken to a revegetation site. It can also be carried on clothing or vehicles. Myrtle rust spores are microscopic and can easily spread across large distances by wind, or via insects, birds, people, or machinery.

If it becomes widespread it will impact all of New Zealand’s Myrtaceae to some degree and we are likely to lose some native species in their natural state. Ecological integrity will be compromised in places where myrtles are a dominant species. It is also likely to affect commercial activities (e.g. manuka honey industry), tourism, recreation and landscape values.

It is very important community planting groups, volunteers and all those who go into the forest follow certain hygiene protocols to restrict the spread of the wind-borne disease. Revegetation work is a potential vector for spreading myrtle rust. People doing voluntary conservation work of any type, could inadvertently spread the disease.

Community Group Action

If you are growing plants

  • Commercial plant nurseries are required by MPI to comply with NZPPI protocols of plant hygiene. Other plant nurseries are requested to comply with these protocols so the next link in the chain is where the plants go to from the nurseries.
  • At this time, DOC is encouraging community groups to adopt the same protocols to lower the possibility of any further spread of myrtle rust and to keep an eye out for myrtle rust.

If you are planning to plant

  • For groups located in Northland and Taranaki regions, Myrtaceous plants should not be planted at any planting days coming up, unless the disease is declared to be eradicated before the proposed planting date. For all other plant species, it is advisable to ensure the nursery of origin has been adhering to the NZPPI hygiene protocols and you keep a record of number of plants by species, their origin and planting location, as these plants can still be a vector.
  • For all other regions, planting of Myrtaceous species may proceed if plants are not sourced from Northland or Taranaki. Ensure the nursery of origin has been adhering to the NZPPI hygiene protocols and keep a record of number of plants by species, their origin and planting location.

For commercial nurseries, you can check the Nursery Management Declaration (http://nzppi.co.nz/documents/pests/MR-Nursery-Management-Declaration.pdf) from the relevant supplier nursery to ensure plants were inspected and treated at the source nursery as per NZPPI guidelines. This will ensure appropriate checks are in place at two levels (supplier nursery as well as the receiving nurseries) to identify and remove suspect Myrtle Rust infected plants from the trade chain.

Hygiene Recommendations for Community Groups

  • Check any myrtaceae plants for symptoms of myrtle rust
  • If you are bringing myrtaceae plants in, check the site the plants are coming from has been surveyed for symptoms of myrtle rust.
  • If you suspect myrtle rust, please take a photo and report to MPI (0800 80 99 66). Don’t move any plants, produce or gardening equipment offsite until you hear back from MPI.

If you find anything suspicious

1. Do not move the plants from the site or your truck.

2. Take photos of the suspected myrtle rust and the whole plant.

3. Do not attempt to touch or collect samples as this may increase the spread of this disease.

4. If possible, isolate the plants with an igloo-hoop-like plastic cover.

5. Call MPI’s exotic pests and diseases hotline on 0800 80 99 66.

More information

More information can be found on

Please feel free to share this information with anyone you feel will be interested. We’ll provide further updates as they come to hand if the situation changes, but please follow us on Facebook for more frequent updates.