Disease control in forestry

All trees are prone to some level of disease threat. Some diseases only affect certain species of tree or certain regions of forestry.

Kauri dieback

Kauri dieback is threatening New Zealand's kauri trees with extinction. The Ministry for Primary Industries (MPI) is working with central and local government, tangata whenua and the wider community to stop the spread of the disease.

Pine needle diseases

Pine needle diseases can cause large scale damage to plantation forests and have significant economic impact. For information on how to recognise and treat these diseases, see our pages on pine needle diseases.

Myrtle rust

Myrtle rust is a serious fungal disease that affects plants in the myrtle family. Plants in this family include the pōhutukawa, mānuka and rāta.

The Myrtle rust website has a range of guidance and resources on myrtle rust including where it's been found, what plants it affects, how to identify it and minimise its impacts.

Forestry disease database

Farm Forestry New Zealand has a forestry disease database which can help with disease identification and control methods.


In New Zealand, symbiotic fungi from the genus (a level of grouping plants or animals that's broader than species) Trichoderma are used to protect against pathogens (organisms that cause disease). A symbiotic fungus is a type of organism that produces spores and relies on its relationship with other organisms in its environment to survive.

When the fungus is applied to soil at the same time as seed, it colonises the outer shell of the seed and provides a protective layer that shields the seed from diseases in the soil.

The forestry industry has invested heavily in research into these fungi. If successfully managed and applied, they have the potential to protect against current threats and help trees protect themselves from unfamiliar diseases.

Regional pest management plans

Many regional and district councils require landowners to manage and control certain pests, weeds and diseases. Check with your council to find out what responsibilities you may have.

Pests and diseases database

See Ministry for Primary Industries tree pests and diseases list for more information.

Monitoring pests, weeds and diseases

Tell the Ministry for Primary Industries if you see anything unusual.