How to recognise myrtle rust

Ramarama with raised yellow pustules indicating myrtle rust. Ramarama is an endemic species of evergreen myrtle shrub which grows to a height of 8m. 

Willow myrtle with red-brown lesions indicating myrtle rust. Agonis flexuosa is a species of tree in the myrtle family. It has clusters of small white flowers that grow on the branches in between the leaves in spring and summer. 

Pōhutukawa with grey spores more common in winter. Pōhutukawa is New Zealand's Christmas tree, and holds a prominent place in Maori mythology. Although the fortunes of pōhutukawa and rata have changed for the better, they are still threatened by people and pests. Photo credit DOC. 

Pōhutukawa with myrtle rust yellow pustules. Pōhutukawa is New Zealand's Christmas tree, and holds a prominent place in Maori mythology. Although the fortunes of pōhutukawa and rata have changed for the better, they are still threatened by people and pests. Photo credit DOC. 

Rātā where leaves have become buckled and are dying off due to myrtle rust. Rātā trees, along with the pōhutukawa, are one of the best known native trees in New Zealand. Native birds benefit from rātā, but as possum numbers increase the threat to native birds and to rātā has also grown.

Ramarama with older grey-white pustules on stem and leaves indicating myrtle rust. Ramarama is an endemic species of evergreen myrtle shrub which grows to a height of 8m. 

Ramarama with raised yellow pustules on lower surface of leaf indicating myrtle rust. Ramarama is an endemic species of evergreen myrtle shrub which grows to a height of 8m. 

Ramarama with raised yellow pustules on upper surface of leaf indicating myrtle rust. Ramarama is an endemic species of evergreen myrtle shrub which grows to a height of 8m. 

Feijoa with raised yellow pustules indicating myrtle rust. Acca sellowiana, a species of flowering plant in the myrtle family, Myrtaceae, is native to the highlands of southern Brazil, eastern Paraguay, Uruguay, northern Argentina, and Colombia. It is widely cultivated as an ornamental tree and for its fruit.

Lilly Pilly with raised yellow pustules and red-brown lesions indicating myrtle rust. Syzygium smithii is a summer-flowering, winter-fruiting evergreen tree, belonging to the myrtle family Myrtaceae. It shares the common name "lilly pilly" with several other plants. In New Zealand, it is commonly known as 'monkey apple'

Mānuka with yellow and grey pustules on leaves with small red-brown lesions indicating myrtle rust. Leptospermum scoparium, commonly called mānuka, manuka, manuka myrtle, New Zealand teatree, broom tea-tree, or just tea tree, is a species of flowering plant in the myrtle family Myrtaceae, native to Australia and New Zealand.

Eucalyptus with raised yellow pustules indicating myrtle rust. Eucalyptus is a diverse genus of flowering trees and shrubs in the myrtle family, Myrtaceae. Photo credit CSIRO.

Eucalyptus with raised yellow pustules on the underside of the leaf. Eucalyptus is a diverse genus of flowering trees and shrubs in the myrtle family, Myrtaceae. Photo credit CSIRO. 

Eucalyptus with raised yellow pustules and brown lesions. Eucalyptus is a diverse genus of flowering trees and shrubs in the myrtle family, Myrtaceae. Photo credit CSIRO

Over time the characteristic yellow spots can darken and become brown-grey. This is myrtle rust on a Ramarama plant. Ramarama is an endemic species of evergreen myrtle shrub which grows to a height of 8m. It is native to New Zealand.

Bright yellow powdery eruptions of spores appear on both sides of the Eucalyptus leaf. Eucalyptus is a diverse genus of flowering trees and shrubs in the myrtle family, Myrtaceae. 

Bright yellow powdery eruptions appear on the underside of the young ramarama leaf. Ramarama is an endemic species of evergreen myrtle shrub which grows to a height of 8m. 

Bottlebrush with raised yellow pustules and red-brown lesions on the leaves and stem indicating myrtle rust. Callistemon is a genus of shrubs in the family Myrtaceae. The entire genus is endemic to Australia but widely cultivated in many other regions including New Zealand.