Accelerating landscape scale restoration of native forest

Project Status: Current

Introduction

Trees That Count (TTC) in collaboration with Tāne’s Tree Trust (TTT) have initiated a project to establish a network of demonstration planting areas nationwide with seed islands as a method to accelerate restoration of native forest on a large scale.

The project aims to identify representative sites throughout New Zealand, including marginal erosion-prone hill country, to explore the concept of planting small groves of key native tree and shrub species within degraded landscapes that will act as seed islands to accelerate natural regeneration to high native forest long term. The project is being implemented in collaboration with stakeholders and other potential partners such as landowners, iwi, community landcare groups, NGOs and local authorities. It is recognised that encouraging natural regeneration must be in combination with pest browsing animal control, selective exotic weed control, and ideally bird and seed predator control.

Fieldwork undertaken in 2024

The first year of this project has seen the selection of five demonstration seed island sites and eight satellite seed island sites. Planting has been completed for two of the demonstration sites including baseline and first year measurements. Planning is well underway for the remaining three demonstration sites to be planted during the next milestone periods. A map of new zealand with black text Description automatically generated

Demonstration seed island sites

In collaboration with project partners, three sites are located in the North Island and two in the South Island (Figure 1).

Waipoua Forest Trust - Pukemiro Ridge, Northland:
- Waipoua Forest Trust, with the aim of regenerating previously cleared land bordering the Waipoua Forest to protect and restore kauri at landscape scale.
- Ten seed islands of high forest tree species were planted in August 2024 within the recently planted nurse cover species and baseline measurements completed.
- Native tree species planted within the seed islands include kahikatea, pukatea, tairaire, puriri, tōtara and kohekohe.
Kōkako Ecosystem Expansion Project (KEEP), Rangiuru, Bay of Plenty:
- KEEP is a collective with an ambitious, multi-generational project with a vision to support the long-term sustainability of kōkako in the Bay of Plenty.
- Eight seed islands were planted in mid-2023 as part of Matariki, with the local school, landowners and iwi as the first of many stepping stones across farmland linking the two kōkako populations.
- First year measurement has been completed, data analysed, and Year 1 performance reported.
Pihitea Station, Pouawa, Tairāwhiti:
- Moderately steep sheep and beef cattle farmland with flood-prone waterways typical of East Coast stations.
- Wide riparian buffers have been fenced to exclude stock comprising rank grass and scattered poplars.
- Planning underway to plant a minimum of 10 seed islands above the flood line within fenced wide riparian areas in 2025 with native trees and shrubs.One year after planting seed islands in mid-2023 at the KEEP site that will become a ‘stepping stone’ across farmland for kōkako migrating between distant native forest remnants in the Bay of Plenty.
Mount Vernon Park, Port Hills, Christchurch:
- Port Hills Park Trust Board, with the aim to conserve and enhance the natural environment and provide public recreation opportunities.
- Planning is underway to continue planting significant areas of the park in native shrubland and forest cover.
- Ten seed islands have been planted in October 2024 within steep hill country retired from sheep grazing either side of a well-used public access track.
- Native plants comprise a mixture of shrubs and trees including shrub nurse species (kōhūhū, mingimingi, ngaio, koromiko) and tree species (matai, kahikatea, tōtara).
Remarkables Station, Queenstown, central Otago:
- QEII National Trust, 900ha gifted by owners of Remarkables Station Dick and Jillian Jardine, located near the entrance to the Remarkables ski field.
- Twenty small seed islands have been planted within cut gaps in bracken, taking advantage of the shelter required to improve early survival and growth.
- A higher proportion of trees to shrubs are to be planted, including Hall’s tōtara, red and mountain beech, kōwhai and broadleaf with hardy local shrub species.Pre planting inspection in July 2024 of the seed island sites at the Remarkables Station, Queenstown. Natives will be planted within gaps cut in the bracken that will provide shade and reduce rabbit and hare access.

Satellite seed island sites

Satellite sites require less intensive planning and monitoring by the project team. The project will provide some input into these satellite sites where landowners and community groups are keen to be involved. These satellite sites will extend the number of seed islands to a wider range of landscapes and regions nationwide (Figure 1).

Kawhia, western Waikato – project partners Tainui-Kawhia Inc, local community and councils. Two areas of seed islands planted over the last two years on highly exposed backdune sites. Monitoring and maintenance underway.
Inspection of seed islands planted with a range of native trees and shrubs surrounding a small pond within the backdunes at the Kawhia site, western Waikato.Whangara Station, Tairāwhiti – project partners, iwi, station owners and local Landcare community groups. Comprises 400ha of retired coastal farmland where seed islands will be established by landowners in 2025 and monitored by the project team.
Waikereru Ecosanctuary, Gisborne – project partners Waimata River Care and Longbush Ecological Trust. Over 20 seed islands recently established within natural gaps or regenerating kānuka along lower slopes of erosion-prone, formerly grazed steep hill country.
Tūhaitara Coastal Park, north Canterbury – project partners Te Kōhaka o Tūhaitara Trust, local schools and service groups. Tōtara dominated seed islands planted within recently logged pine backdunes along with nurse shrub species. Baseline and first year assessments have been completed.
Matemateonga Range, eastern Taranaki – project partners Eight Hundred Trust Kiwi Reserve. Extensive plantings of mānuka at wide spacing to be established with seed islands of canopy trees, including podocarps and native tree hardwoods in 2025.
Mangarara Station, southern Hawke’s Bay – project partners including landowners and Balanced Forestry. Two 10ha areas of erosion-prone hill country recently retired from grazing, planted with mānuka over the last two years. Seed islands of selected native tree species to be planted in 2025.
The Tūhaitara Coastal Park seed island planting site in north Canterbury. Seed islands were planted on inland dunes after pines had been clear-felled, part of a multi-generational vision by project partners Te Kōhaka o Tūhaitara to see coastal podocarp forest re-established along the north Canterbury coastline.Waingake Restoration Area, Tairāwhiti – project partner Gisborne District Council. Water catchment area for the city recently clear-felled of pines planted with seed islands of native tree canopy species within regenerating shrubland over the last two years.
Te Kōawa Tūroa o Takitimu, Te Anau – project partners Te Waiau Mahika Kai Trust. Planting seed islands to be initiated to convert rank exotic grassland within their 445ha site to provide a seed source of native species. The aim is to protect and enhance the ecological and mahinga kai values and to promote use and reconnect Murihiku Runanga with their land, and more broadly Ngai Tahu.

Methods for establishing seed islands

A run-sheet has been drafted for ensuring a consistent approach to selecting and establishing seed islands across all sites to allow comparison of performance. This has been provided to project partners collaborating in establishment and management of the sites nationwide. The design and implementation of seed islands is flexible to allow for site-specific variation in site characteristics, scale of planting, differences in species appropriate for each region, and allowance for local best practices in planting and early management of natives.

The size of seed islands is determined by the gap or micro-site available for inter-planting natives, or as dictated by the density of planting where a nurse cover may already have been established. Monitoring follows the standard plot-based procedures developed by Tāne’s Tree Trust and Trees That Count.

The excellent performance of the first seed island site established as part of the kōkako ecosystem expansion project (above). The eight seed islands were assessed using the measurement methods developed by Trees That Count and Tāne’s Tree Trust, involving a circular plot with a fixed radius from a central plot peg (below).Preliminary results

An example of the data analysis, presentation of results and interpretation is provided for the first planted seed island demonstration site – the Kōkako Ecosystem Expansion Project (KEEP) – located in the western Bay of Plenty.

First year performance on this site has been exceptional:

Survival for all species is over 90%;
Average height has tripled for most species and doubled for the remainder. The best performing species are over 120cm high 12 months after planting;
Average plant vigour has remained excellent; and
Damage by various injurious agents has been minimal.