Protecting our forests from pests & diseases

Protecting our planted and natural forests from insect pests, pathogens and invasive weeds is vital. Scion is New Zealand’s leading authority on forest biosecurity.


Forest diseases

Preventing, diagnosing and controlling plant diseases that affect the health of New Zealand’s forests is the focus of our forest pathologists’ work. Our science also helps government agencies to prevent harmful pathogens from entering the country. We specialise in:

  • Biosecurity, surveillance and diagnostics
  • Chemical control of forest pathogens
  • Biological control with fungi and viruses
  • Modified silvicultural regimes to minimise the effects of diseases, such as Dothistroma and Cyclaneusma
  • Inducing resistance in trees through micro-organisms or genetic selection
  • Improving seedling growth using ectomychorrizae.

Scion diagnostic service is underpinned by our Forest Health Collections of fungi, insects and wood and bark boring insects intercepted at New Zealand's border.


Read and download Field assessment, control and identification of common foliage diseases of pine in New Zealand [pdf]


Andrew Cridge, Portfolio Leader, Trees for High Volume Wood Products

E Heke e Heka! app

Scion developed an app to empower rangatahi (young people) and the community with knowledge about myrtle rust. Historically, myrtle rust scientific resources, particularly in  Te Reo Māori, have not been widely accessible.


Addressing the threat of Phytophthora

Scion led the collaborative programme Healthy trees, healthy future to address the threat of Phytophthora species to New Zealand’s agriculture, horticulture and forest estates. Phytophthora, a genus of soil, water or air borne plant pathogens, pose major challenges to global biosecurity.

This programme builds on our existing programmes for red needle cast, kauri dieback and other diseases caused by Phytophthora species.


Darryl Herron, Team Lead, Pathogen Diagnostics and Collections

The International Plant Sentinel Network

This network taps into vast collections of plants grown in 2,500 botanic gardens and arboreta worldwide to help with border biosecurity. Staff of botanic gardens and arboreta regularly monitor plant health, photograph pests and diseases and collect samples for analysis and identification. These data are available to collaborators to help predict and prevent an invasive insect or pathogen from entering a country.

New Zealand's Better Border Biosecurity (B3) contributes to this initiative, along with Scion and Canterbury University.


Andrew Cridge, Portfolio Leader, Trees for High Volume Wood Products

Forest insect pests

Global trade places our forests under constant threat from invasive pests. Our entomologists are concentrating on developing rigorous pest surveillance, eradication and control systems.

Scion has dedicated containment and insect rearing facilities that enable us to provide quality forest protection research.

We specialise in:

  • Biological control
  • Biological and ecological risk assessment
  • Biosecurity, surveillance and diagnostics
  • Alternative quarantine treatments
  • Biodiversity and ecosystem function

Our science is supported by access to the national Forest Insect Collection and BUGS database.

Scion is a member of the collaborative Better Border Biosecurity (B3) partnership.

Find forest timber and insect information.

Managing the poplar sawfly [pdf]

Biological control

Our scientists identify, evaluate and rear biological control agents for both weeds and insect pests.

Examples of our biological pest control work include:


Toni Withers, Scientist, Entomology

Containment and insect rearing facility

Invertebrate transitional and containment facility

Our transitional facility enables us to manage the biosecurity risks associated with organisms. We use this facility to rear insects for eradication and biological control purposes, for host testing, and to conduct research on a wide range of forestry-related topics for government, industry and the general public.

PC2 Microorganism containment facility

Scion’s containment facility makes it possible for our entomologists to manage and contain the biosecurity risks of new organisms, and to prevent them from becoming established in New Zealand. This includes microorganisms or cell cultures that are designated new organisms by the Environmental Protection Authority (EPA), those that are not known to be present in New Zealand and those not approved for release.

This facility enables Scion to provide a quality forest pest and disease diagnostic and identification service, and scientific research to government, industry and the general public. We maintain microorganisms in containment:

  • As reference material
  • For small-scale experimentation
  • To develop new diagnostic techniques
  • For risk assessment.

The facilities are registered under the Ministry for Primary Industry (MPI) standards:

  • Transitional and Containment Facility for Invertebrates (Standard 154.02.04)
  • MPI/EPA Standard Facilities for Microorganisms and Cell Cultures2007a

The containment facility is operated under strict containment protocols and only trained personnel have access.

Read how Raising healthy pests will gain insight into their behaviour


Quarantine Manager

Invasive weeds and wildings

Highly competitive weeds introduced to New Zealand include broom, gorse, buddleia, blackberry, and many others. Managing these weeds during the establishment of plantation forests improves tree survival, growth, crop uniformity and productivity. We provide a range of management tools for weeds and wilding conifers that are both economical and environmentally sustainable.

Weed control

Scion’s weed management research focusses on:

  • Weed risk analysis to identify and manage high risk species
  • Herbicide risk to minimise the environmental impacts associated with chemical sprays. Our recent research has confirmed that the most effective weed treatment is the current industry standard, and that the environmental risks are low
  • Alternatives to herbicides using non-chemical methods
  • Weed ecology
  • Vegetation management tools.

Read about:

Wilding conifer management

Wildings are a result of seedlings from introduced trees, mainly conifers, spreading and establishing in areas not designated for forestry. Wilding conifers are a serious economic and environmental problem. Existing populations of wilding conifers are being treated but cleared land is being re-invaded. For the National Wilding Conifer Control Programme to be successful, effective strategies to create long-term resistance to re-invasion on treated land are essential.

Scion has been researching wilding conifer ecology and management for over 20 years, supporting regional authorities and landowners in their efforts to control wildings.

Scion’s Dr Thomas Paul leads the MBIE Endeavour Programme: Vive La Résistance: Achieving long-term success in managing wilding conifer invasions.


Thomas Paul, Scientist, Forest Ecology and Management

Pest management

Scion helps forest growers and government agencies to identify, manage and protect against harmful forest insect pests, pathogens and invasive weeds in planted and indigenous forests.

We have supported a number of successful pest eradication campaigns in New Zealand, including painted apple moth, white spotted tussock moth, Asian gypsy moth, fall webworm and eucalyptus leaf beetle.

Our expertise in spray application technologies and risk assessment tools are used to develop best practices for aerial spraying, especially near urban environments where off-target spray drift can have serious consequences.

Border Surveillance

Pests can be introduced to New Zealand via a number of pathways. Robust biosecurity surveillance is crucial to protect our exotic planted and indigenous forests.

Scion’s extensive research, diagnostic and archival resources underpins New Zealand’s border surveillance system. Our forest health reference laboratories include containment facilities, a molecular diagnostic laboratory, and extensive databases and reference collections for insects, fungi and woody plants.

Scion is part of the Better Border Biosecurity (B3) alliance dedicated to protecting New Zealand’s plant-based biosecurity.

Pesticide application

Our research into aerial and ground-based pesticide application technologies has improved the environmental and economic performance of both.

We develop cost-effective biological or synthetic pesticides that provide maximum performance with minimum environmental impact. Much of this research is carried out in collaboration with Plant Protection Chemistry NZ.

Track sprayer facility

Scion’s large scale, precision track sprayer facility allows us to test the many elements that influence spray deposition and retention on the forest canopy in a controlled environment.

We can replicate realistic simulation of spray deposition in a large, enclosed laboratory. The adjustable spray boom allows us to study the effects of canopy type and density on spray deposition. Our research has been used to improve spray deposition models such as the widely used AGDISPTM aerosol spray drift model, and to reduce off-target spray movement such as drift, soil transport and volatilisation.

We use the precision track sprayer to help forest growers and government biosecurity agencies optimise pesticide dosage to control invasive insects, pathogens and weeds on a variety of canopy types.

Our research has resulted in effective aerial spray programmes for the eradication of eucalyptus leaf beetle (Paropsisterna beata) and for the control of needle diseases in planted radiata pine forests.


Watch the tracksprayer in action [YouTube]

Pest eradication in the urban environment

We are improving pest surveillance and eradication methods so they are safe to use in urban areas.

Our pest management specialists are developing a toolkit of advanced spray technologies, such as the spot gun and spot-boom methods designed for targeted use in sensitive areas.

Toolkit for the urban battlefield

Scion is leading an inter-agency, MBIE-funded research programme ‘Protecting New Zealand’s primary sector from plant pests: a toolkit for the urban battlefield’. The programme responds to the urgent need to improve pest surveillance and eradication tools for use in urban areas located near sea and air ports.

The programme aims to improve surveillance, develop low-impact eradication technologies, and develop socially acceptable pest control protocols to help agencies apply appropriate risk and communication strategies for urban communities.

Improvements to country’s biosecurity as a result of this programme, are worth an estimated $2.5 billion (net) to the sector. This research programme is linked to Better Border Biosecurity (B3) and the Biological Heritage National Science Challenge.

Rubrics – an assessment tool for the urban biosecurity toolkit [pdf]


Tara Strand, General Manager, Forests and Landscapes
Brian Richardson, Principal Scientist, Plant Protection Physics and Chemistry