Projects
Restoring the indigeous forests
Summary
Restoring the indigenous forest
NZ Forest Restoration’s programme is designed to re-establish indigenous forest over the long-term, using carbon income to restore an exotic forest – previously destined for harvest – into a permanent, biodiverse environment.
Within an active and adaptive forestry management regime, restoration is a naturally occurring ecological process of forest succession. Fast-growing pioneer trees provide the right conditions for a slower growing and more complex forest, allowing a range of species to become established as part of a biodiverse ecosystem.
To accelerate and support the natural restoration process, we use the exotic trees as a nurse crop, supplemented by native seed sources. In a well-established programme, which is tailored to each individual site, our project manager, NZCF, undertakes careful management and planned interventions to create the environment for the restoration to a biodiverse native forest.
The restoration model is designed to allow the forest to undergo its natural cycle of growth, development and succession – supported by the active management programme. This means the environment can benefit from the rapid sequestration of carbon when it is most needed – over the next 70 years. Then, as the native trees grow and ultimately succeed the faster growing exotics, they will continue to capture CO2 over hundreds of years. This process will balance any release of carbon that occurs as part of the forest’s natural lifecycle.
The Science of Forest Restoration/ Carbon removals and other benefits of the NZ Forest Restoration project
Dr Len Gillman, Professor of Ecology, Independent Advisor on Forest Restoration
Science
The science of restoration
Over 50 years of local scientific research supports the process of restoration. Our project manager NZCF has had an independent team of forest scientists working on its restoration programme for the last five years. Their findings, and the wider research undertaken in a New Zealand setting, is guiding the operationalisation of active management for restoration at scale.
Using the latest technology
To track progress of restoration and measure the carbon sequestration of the forest we utilise the latest available technology – from multi-spectral imaging to LiDAR analysis – to monitor the growth of the forest and plan for specific management interventions. This will better enable the efficient assessment of the forest structure and growth trajectories at different spatial and temporal scales.
The pest and predator control programme is also supported by the use of a range of innovative technologies, including thermal imaging and AI-operated traps, which use machine-learning to recognise target species.
Key Elements
Managing the forest’s restoration
Site selection
Permanent restoration transitional forestry is a targeted use for otherwise low-productivity areas – land that is steep, erosion-prone, hard to get to and difficult to maintain for its current harvest management regime – making it the ideal alternative to erosion prone land that is better suited to permanent forestry.
Pest Management
To protect the health of the exotic nurse crop and – critically – the growth and development of native species, a comprehensive and professionally-managed pest management programme is vital to the success of a restoring native forest. Our project manager NZCF currently invests more than $2 million per annum on the largest private pest management operation in New Zealand. As part of the programme, predator control – to remove animals like rats, stoats, weasels and hedgehogs through humane and effective trapping – not only supports restoration but also significantly enhances biodiversity in the forest. [Read more on light control]
Light control
One of the keys to native restoration is the role – and, where required, the management – of the forest canopy and introduction of light to the forest floor. To support the restoration process, Variable Density Thinning (VDT) and the creation of lightwells are used to manage the forest canopy.
[Read more on light control]
Supplementary seed sources
As part of the site selection process, selecting forests with remanent seed sources located close to the site, is important to the restoration process. To support the forest succession process, targeted native enrichment planting can also be established within the site as required. Based on extensive, site-specific research of each site, its history and the local environment, this targeted native enrichment planting helps reintroduce a range of native species. In particular, the supplementary planting process focuses on slower growing canopy species, which will eventually form an important part of the long-term structure of the restored forest. [Read more about supplementary seed sources]
Fire management
Fire mitigation planning starts from the design stage of each forest. As well as ensuring appropriate firebreaks are present, other measures include the identification of water sources, and targeted grazing, thinning and targeted fuel reduction in key areas, and the introduction of low-flammability native species in sensitive areas.