Pukenui Western Hills Forest Charitable Trust

Pest control

It is hard to believe that the dreaded possum, scourge of our native forests, orchards and rose gardens, was once a protected species!

The Pukenui Forest Trust is currently removing as many possums as it can, using state-of-the- art trap and poison technology that is currently available.

Possum removal in the forest has been on-going now for several years, and the forest health has improved noticeably. One of the favourite foods of the possum in winter are the flowers of our beautiful kohekohe tree. This species is classed as sub-tropical and flowers in winter when there is not much other food about. Each flower has a small amount of nectar in it, which the possums love. Now, for the first time in quite a while, the kohekohe trees have flowered uninterrupted and are now setting seed.

Bait station
Gerry Brackenbury, ranger, and volunteer Marcus Bax beside a hundred modified bait stations ready to kill rats and possums in the forest.

Another pest that has been chomping into the lower forest canopy are goats. Again, these wild animals have been living in Pukenui Forest for a long time, and now, over the last two years, professional hunters have removed up to 500 animals. This will allow the trees, the shrubs, the ferns and even the orchids to flourish once again.

Another major animal pest in the forest are rats. We have two species of European rats in NZ, rattus rattus and rattus Norvegicus, and between the two of them, they eat practically everything, including seeds, fruit, insects and birds eggs.

The combination of possums and rats has seen the almost total disappearance of native birds in the forest, particularly our beautiful native pigeon (kereru) and tui. These have been reduced to just a few birds when once they could be counted in their thousands. The pigeon is now the only bird left that has a crop large enough to cope with large fruiting trees like the taraire and puriri. If the pigeon disappears, what will spread the seeds of our trees?

Finally we cannot talk about pests and predators without mentioning the dreaded stoat. This was probably THE most stupid thing early colonists did to bring into the country this born-again killer. Stoats are highly intelligent predators which can swim, climb trees and leap tall buildings! This member of the mustelid family is the main reason why our kiwi have just about disappeared. Along with uncontrolled dogs, stoats kill kiwi on sight, especially kiwi chicks. We will be targeting stoats in our pest-control programme using a trap called a DOC 200. These will eventually cover most of the forest and, hopefully, within the next two years kiwi will be returned back to Pukenui Forest where they belong and can safely roam filling the night with their unique call.


Pukenui is close to the City of Whangarei and has been bordered by gardens over a long period of time. Many species introduced by gardeners over time have ‘jumped the fence’ and begun to invade our natural areas. Ginger, climbing asparagus, Taiwan cherry, bangalow palms are some commonly found species on the eastern slopes of Pukenui forest near the urban area. In some areas invasive species have penetrated far into the forest, carried there by wind, birds and sometimes trampers boots.

Invasive plants, especially those that form dense mats on the ground, have a long term impact on the forest. These plants change the food source and availability for birds and insects. Invasive ground cover plants prevent the establishment of seedling trees that will replace the forest giants when they eventually die. Invasive opportunist trees like Taiwan cherry and banglow palm often grow faster than our native trees and become the dominant species when light wells are formed from tree fall. Our native birds are adapted to the year round food source provided by native forest trees and plants.

Whangarei District Council is undertaking weed control in the Coronation Park area of the hills and encouraging the removal of invasive species from neighbouring gardens. Volunteers and small groups of residents have begun to work on the weeds on the border of the forest but there is much more to be done.

If you want to make a difference to the forest in your area, get a few neighbours or friends interested and form a weedbuster group. Contact the Pukenui Western Hills Forest Trust or Weedbusters for assistance.

Myrtle rust fungus in Bay of Islands

Key Messages:

  • The damaging plant fungus myrtle rust has been found for the first time in mainland New Zealand.
  • Urgent actions are underway to understand the situation and what we need to do.
  • The nursery where the disease was found has been locked down.
  • If people believe they’ve seen signs of myrtle rust - do not touch it. Take a photo if possible. Phone MPI on 0800 80 99 66 immediately.

Full background messages:

  • The fungal disease myrtle rust has been found for the first time in mainland New Zealand on plants at a nursery in Kerikeri, Northland.
  • The nursery owner reported suspicious symptoms on plants to MPI on the evening of Tuesday 2 May 2017 and a positive identification was made late night on Wednesday 3 May 2017.
  • MPI was already working with iwi, the Department of Conservation and other partners including industry and councils in response to the discovery of the disease on Raoul Island in the Kermadecs north of New Zealand in March.
  • An urgent biosecurity response has been mounted and operational staff are in the field in Northland. There are expected to be up to 20 staff in the area shortly.
  • The affected nursery is under tight biosecurity controls and movements on and off the property of plants and people are restricted. The property has been treated with a fungicide spray.
  • MPI has urgent work underway to determine the scale of the incursion and to trace where materials from the nursery have gone.
  • Rust diseases such as myrtle rust are notoriously difficult to control and so far there has never been a successful eradication of this disease.
  • Myrtle rust is a fungal disease that affects plants in the myrtle family, which includes some of New Zealand’s iconic species such as pohutukawa and manuka, as well as production plants including eucalypts and feijoa.
  • We do not know how it will affect plants in New Zealand. Overseas its impacts have varied widely from country to country and species to species. It is, however, likely to have significant impacts.
  • Myrtle rust spores can travel long distances on the wind. They can also be carried on people, clothing and equipment. The disease is widespread along Australia’s eastern seaboard and it has long been regarded as likely the fungus would ultimately reach New Zealand shores.
  • The Ministry has notified key partners about the suspected incursion, including DOC, local iwi, potentially affected industries and the regional council.
  • The nursery owner is to be congratulated for making such a prompt notification to MPI. His actions are a great example of what we are working to achieve through the Biosecurity 2025 Direction Statement - having a biosecurity team of 4.7 million people on the lookout for biosecurity risk. Biosecurity is everyone’s business!
  • Members of the public are encouraged to be alert for signs of myrtle rust. It appears as bright yellow/orange powdery patches on leaves of myrtle plants and affected leaves may buckle or die off.
  • If you believe you have seen myrtle rust, DO NOT TOUCH IT or try to take a sample. Take a photo, including of the affected plant and contact MPI on 0800 80 99 66.

Full information is on the MPI website.

Feral Goats

Feral goats

Estimates indicate that more than 250 goats may be present in New Zealand's forests. Feral goats can have major effects on forest under-storey because of selective grazing pressure on preferred species. Goats can devastate the forest under-storey of preferred sites when undisturbed for long periods.

A feral goat herd lives above the Whau Valley dam reserve. Private-landowner control initiatives are reducing this population and it is considered that their control is relatively easy to achieve.

There is some good news re the goat control programme. By July 2011, the cullers had taken out up to 400 animals and the forest recovery is already starting to show.

Advice on weed control

Pukenui Western Hills Forest Charitable Trust