Planting the seed to regenerate New Zealand's native trees

“Recloaking the whenua (land) with native trees” is how scientist Dr David Bergin is describing an exciting new project between Z and native tree planting charity Trees That Count, an initiative that aims to restore native forest across Aotearoa.  

“We’ve got around one million hectares of steep eroding hill country in Aotearoa, which should have never been deforested,” says David, who works as a science and technical advisor for Project Crimson, which manages Trees That Count.  

“The new project – in collaboration with Tane’s Tree Trust, who will be providing technical support – will focus on demonstrating a concept known as ‘seed islands’ at selected sites across the country. A seed island is a small area of intensive planting of your selected target species – in this case, native trees and shrubs – that will fit within a manageable area,” David explains. “Over time, the trees will start seeding, and birds and the wind will then start distributing that seed to the rest of the marginal open hill country to start the process of regenerating our native forests.” 

David says this pilot program, which if successful, has the potential to provide huge ecological, environmental, and cultural benefits for the country. The aim is to work with nature to encourage natural regeneration, rather than relying entirely on expensive large-scale blanket planting. The project will demonstrate establishment of seed islands aimed at increasing seed sources of native forest species that were once abundant at each location. Five separate locations from Northland to Otago have been identified, with the purpose of showing how the concept can be more widely adopted by landowners to encourage natural regeneration.  

“Think of it like landscaping that you would do in your garden,” says David. “It requires the same attention and care by targeting the best sites within a landscape where there is likely to be increased success in early survival and growth. Seed islands need regular monitoring and weeding, as well as management of bird and seed predators, to increase seed production and the mechanisms of dispersal to effectively recloak our whenua in the long term with a diverse native forest cover. Let our natural drones do the hard work – the birds and the wind – to help disperse seed across our wider degraded marginal landscapes along with essential pest animal and weed control.”

The start of something big 

The idea to “recloak our whenua” began when representatives from Z and Trees That Count contemplated how they could increase native tree planting and restoration to address biodiversity loss, and find innovative ways to make a difference.  

Abbie Bull, Z’s Head of Sustainability and Community, says the two organisations were aligned in their values and that Z was specifically interested in investing in a project that could address barriers to large-scale native planting restoration. 

“What’s super exciting about this project is the potential to develop and prove an approach that will improve the affordability and effectiveness of large-scale regeneration projects, that can then be applied to other projects around the country,” says Abbie. 

Z and Trees That Count have worked together on various projects since 2016. Abbie says that the support that Z is providing is part of its $1 million biodiversity fund that supports projects aiming to accelerate nature restoration and achieve meaningful social and environmental benefits. 

“As a business, we have impacts on and are dependent on nature,” Abbie explains. “We believe we have a responsibility to take action, to enhance the resilience of nature, communities, and our climate in an integrated way.” 

Rocky terrain 

Melanie Seyfort, Head of Marketing and Partnerships at Project Crimson, says the benefit of this project is that researchers will be able to discover best practices and have the ability to re-establish our native trees across once forested landscapes nationwide, from the steep slopes of Coronet Peak in Queenstown to the coastal forests of Northland.  

“We’re going to be planting trees in some pretty challenging exposed sites, from lowland to higher elevation sites where native forest occurred pre-human arrival but is now highly degraded,” says Melanie.  

“The ability for us to trial things in these areas allows us to learn how we can assist faster regeneration combined with supplementary planting methods. For us, it’s about creating a template and promoting our findings on what will work. Any landowner, iwi or community group that wants to restore their land – in particular in areas that are tricky, steep and marginal – will then have a tool kit in terms of how to achieve this.” 

David says the native trees they will be planting will be varied and will depend on the area and what the local forest types are. Planting a certain species of tree in a certain way, in a certain location, at a certain time of year, will contribute to a wide range of environmental and cultural benefits, from increasing local indigenous biodiversity to reducing erosion of steep hill country and improving water quality.

“It comes back to the adage ‘right tree, right place’. The species range will change from one end of the country to the other to mimic what was originally and already there. In Northland, for instance, we will be targeting kauri and tōtara, and at the other end of the country, in Otago, we will be targeting beech species.” 

A team effort

David says the project will be reliant on support from the communities that will benefit and be impacted by its findings.  

“It will take a village for this project to be successful. We want to grow together in terms of how we can demonstrate the effectiveness of establishing seed islands and promote the regeneration of native forests in our marginal hill country,” he explains.  

“If we didn’t have partnerships with the landowners, schools and iwi, then we are missing the major point of this whole exercise. We’ve all got to take ownership of these issues, therefore the solutions are going to be local ones. Part of that ownership is understanding the concept and having the willingness to do something about regenerating our native forests.” 

In the long term, the results from this project will help enhance our environment for the benefit of all.

“Native forests, along with associated wetlands, act like a sponge over our hill country. When you get rainfall, it moderates the flow of water into the lower catchment and reduces flooding. They also provide habitat for our native bird and insect species and have significant long-term carbon storage potential.”