If you live in New South Wales, you’ll know how important properly caring for your trees is, especially with the scale of eucalypt dieback which has accelerated dramatically over the past decade. Read this guide for more advice on the most common tree diseases and pests to look out for to protect your home and land.

Quambalaria Shoot Blight

The most common tree disease in New South Wales is Quambalaria shoot blight, a pathogen found on a large scale in the Corymbia plantations. It is an infection by the fungus Quambalaria pitereka and damages new shoots and leaves. Other hosts include lemon-scented gum, spotted gum and large-leaved spotted gum. The disease is at its most damaging in wetter conditions, so it’s important to be extra vigilant during periods of high rainfall.


Another common disease is a collective group of fungal leaf pathogens called Kirramyces leaf diseases. These diseases infect both mature and immature foliage in some eucalypts and can cause significant problems in some hardwood plantations. It can also cause significant defoliation of eucalyptus nitens and has been reported to cause infection by stem fungi, with top death increasing the rate of tree mortality across the New South Wales area. 

Myrtle Rust

One of the worsts pests your tree could be at risk of unwillingly inhabiting is myrtle rust. Myrtle rust is a type of fungus that usually affects the plants of the Myrtaceae family. One of the key symptoms to look for are purple spots, but once the infestation ages, these will then turn yellow and could possibly enlarge and meet, which would ultimately cause the tree leaves to twist and deform. If you detect signs of myrtle rust, it’s important to keep other plants away from the affected area and then quickly and thoroughly apply fungicide to kill the spores and prune any infected parts in preparation for felling the tree.

Yellow Crazy Ants

Another pest you definitely do not want invading your tree is the yellow crazy ant. The clue is in the name – this is not a pest to take lightly! The yellow crazy ant is one of the world’s most invasive species. The name ‘crazy’ comes from its ability to move frantically and change its course of direction quickly, making it difficult to catch. They have a golden-brown body of around 4mm long, with their legs being longer than any other ant species. These ants are dangerous as they not only release formic acid but also protect other pests too. To combat this, you should discard green waste appropriately and use insecticides like Fipronil.

Trees are a great addition to your backyard and with the correct care, they can be really enriching. If you’re in New South Wales and are concerned your trees are not getting the care they need, contact Robert Mank Tree Care for specialised advice and tree services. You can keep your garden healthy and fight off infestations and pests with a quick call to our professionals.