Recognising Symptoms

There is no cure for kauri dieback disease, and the disease kills most if not all the kauri it infects. It can be spread by just a pinhead of soil, and you can't tell by looking whether a tree is infected or not. 

There are several physical symptoms of kauri dieback disease and although the absence of these signs doesn't mean a kauri tree is healthy, it is worth keeping these symptoms in mind.

Assessing kauri trees for symptoms is critical in finding where the disease is located. The most common symptoms associated with kauri dieback disease are below:

1. Bleeding Gum

Basal trunk lesions. Not all infected trees show a trunk lesion, and not all trunk lesions are caused by kauri dieback disease.

2. Yellowing of Leaves

Kauri tree leaves could turn yellow as the disease takes effect. 

3. Thinning Canopy

Given the disease strangles kauri by preventing the movement of water and nutrients throughout the tree, the canopy eventually is reduced or thins out over time. The degree of thinning can vary. The below photo compares healthy kauri crowns to severe dieback and dead kauri.

Rating & Canopy symptoms

  1. Healthy crown – no visible signs of dieback
  2. Canopy thinning
  3. Thinning & some branch dieback
  4. Severe dieback
  5. Dead

4. Dead Branches

Dead kauri trees and trees showing severe dieback-like symptoms such as a thin canopy and dead branches.

The last stage of kauri dieback disease is death of the tree itself where there is no canopy of the tree. Most trees infected will eventually die.

To find out how to avoid spreading kauri dieback disease when using the forest,
visit our How to guides. 

Kauri dieback disease can take years to show, treat every tree as though it is infected.