Open Planet Studios x Tahi. Restoring The Balance.

What is the value of a tree, a new seedling, a fern, fungi, soil, a bird, an insect? Now consider the value of them all combined, working together as a system, a healthy functioning ecosystem. That's a whole different equation. The answer is much more than the sum of its parts. Not just a collection of trees, but a thriving diverse forest that captures and stores carbon, regulates water flow, and protects the land. An ecosystem in balance. So why, as we plant more trees for carbon, are we doing it like this? As countries and businesses pursue net zero, tree planting has been fast-tracked. But native complex forest systems are often overlooked and undervalued. Displaced for straight-lined monocultures that nature never intended. Ticking a box for carbon, but a disaster for nature, and therefore people. There is another way, one that values much more than carbon, as an innovative project in New Zealand is proving. Tahi is an 800-acre eco-reserve on the Northland coast, and for the last two decades, the site of a major restoration project. When we first saw the land, it was totally degraded. There was just over 200 acres of standing forest, but there was no undergrowth. It was completely barren. It was a silent forest. It was a dying forest. With forests around the world disappearing at an alarming rate, and global biodiversity plummeting, the plan at Tahi was to restore the native landscape using a whole ecosystem approach, and to scientifically record progress every step of the way. Susan's father, Dr John Craig, is a renowned ecologist celebrated for his work on natural restoration. He knew it would take a lot more than tree planting, and that the answer was to bring back the architects of a native New Zealand forest, the key pollinators and seed dispersers, birds. What do they need to thrive? Very much like us, it's about food, it's about water, and it's about security. Because of the unique challenges faced by New Zealand wildlife, providing security for the species that should be there is only possible if you remove the ones that shouldn't. New Zealand wildlife didn't evolve with mammalian predators. They don't have the ability to cope with them. So when they were introduced by settlers, our wildlife was heavily predated, particularly by stoats and weasels. Stoats in particular have a really high prey drive, basically anything that's moving, so any birds, invertebrates, lizards, even go into nests and eat eggs. So in order to have all the wonderful birds and lizards and insects that belong here, we have to take out the pests. Controlling invasive species is the foundation for everything else, and with a rigorous program in place, the team could turn their attention to Tahi's many different habitats. They restored the dunes along the coast. They restored 20 natural wetlands. And while the existing forest was now protected, the land was so severely degraded, they needed a planting program to help it recover. What you plant and how you plant it really matters. You have to start with the structure of the forest. Different tree species have different root systems, different growth rates, and rather than relying on a few fast-growing species, the job at Tahi was to reconstruct a whole forest with all its vital layers from the ground up. You need those big canopy trees, the slow-growing carbon-dense giants. They dictate the structure and the climate of the whole forest. Then you need the biodiversity-rich trees that rest beneath them. Importantly, this mix of species provides the food and shelter for a variety of birds and invertebrates throughout the whole year. You've got to put a whole ecosystem together to get everything to come and participate. And what we found here is that you create a habitat and a bird arrives. We started with 20 species, we've now got over 70. That's more bird species than are found in most of New Zealand's national parks. With the birds back and doing the job they evolved to do, the forest is now naturally regenerating. The whole system is alive once again. We've planted almost half a million trees, but we have more than eight million seedlings, which shows that it's the birds that really doing the work. In just two decades, the transformation has been remarkable. Tahi is unrecognisable, full of restored places and treasured native species. I'd only be guessing that it is one of the more senior kauri in this area, and has stood here since the time of my ancestors. A very special tree, the guardian of all that you see below us. The kauri tree is one of New Zealand's mightiest and most threatened trees. Where just a few had remained standing, natural regeneration has seen whole groves of new young trees reappear, showing just what can be achieved when we work with nature. Before coming to Tahi, I was a dairy farmer, and I guess in a way I am still farming, but I am farming the forest, I'm farming our wetlands. It's absolutely about putting the cloak, or the korowai, back on Papatūānuku Mātai. Every trait signifies another stitch in the fabric. Everything here has a mauri, everything around us has an energy. It's only when you come out to these places that you feel that energy, you smell it, you see it. This is our living planet. You can feel the transformation. You can clearly see the transformation. And this project can also prove the transformation. The science has always been a priority for us. We've discovered that no matter what metrics we're looking at, we've exceeded our own expectations, but also science expectations of what is possible. The science shows that after just two decades, this thriving ecosystem is generating invaluable benefits above and beyond the carbon it stores. The forest's structural and genetic diversity has re-established the natural hydrology, protecting the land from flooding and nutrient runoff. Any water not absorbed by the forest is captured by the wetlands. And beneath the canopy, deep root systems stabilize healthier soils, significantly reducing erosion and landslides. Together, the forest and wetlands act like sponges, holding water during floods, slowly releasing it during droughts, as nature intended. New Zealand, like many places around the world, is increasingly buffeted by severe weather events. But Tahi's healthy, intact ecosystems mean the land is able to withstand climatic extremes. By generating such detailed scientific data, this project could inform regeneration efforts across New Zealand, and globally. And that could be game-changing. Given Tahi's results in such a short amount of time, my hope is that it will provide inspiration for others around the planet to do similar things. People can learn from this science-based, positive, can-do attitude. This totally degraded land has become a rich ecosystem that is providing all the services that nature can provide, if it's allowed to do so. Importantly, the science shows that this kind of restoration also delivers on carbon. Tahi has mapped the forest from above, using satellite imagery to track changes over time, and LiDAR, a 3D radar tool that reveals the density, height, and diversity of every tree. The true complexity of the forest can now be seen, and its carbon storage measured with unprecedented accuracy. And the story of change is even captured in the trees themselves. And there's the rings, boy. So this is approximately where the restoration work would have started. Tree coring shows clear recovery in the health of the forest since the Tahi project removed pests and prevented grazing. The growth rings just get bigger and bigger. Growth rates in some tree species have nearly doubled, rapidly accelerating whole forest regeneration and significantly increasing carbon storage. The data is clear. Nature is showing us what's working and what needs to change. Yep, yep, and it's just thriving. The results of this whole ecosystem approach are so transformational. The question is, why isn't everyone managing restoration like this? Currently, the financial model is all geared towards monocrops, because carbon is what we've been counting, and monocultures deliver it quickly and simply. But when you include the whole carbon equation, above and below ground, and the many co-benefits, biodiversity, water, soil, resilience, the equation changes completely. In Northland, native trees grow far faster than current carbon models assume, and many of them lock away carbon not for decades, but for centuries. This prudity here, this has only been in the ground for two and a half years. The work here also shows that native species can be planted even in badly degraded soils. It just shows how fast natives can grow. Grown in nurseries for their first year, they establish strong root systems and thrive without the need for pioneer species. We can now measure the complexity of whole ecosystems in much more detail. This transparency allows the financial markets to assign values and monitor that value, so investing in nature becomes a real opportunity. As an ecosystem recovers, its worth increases, generating value and income for investors, for landowners, farmers, foresters, and communities who manage the land. If we do this intelligently, we will all benefit because investing in nature is essential to achieve the kind of planet that we're all striving for. We have allowed so much of our planet to be degraded, and we can see that it's possible to turn back and to come back to healthy nature. We can be a real lighthouse project for what's possible, how resilient nature is, and how rapidly it bounces back. If you give it a little bit of help, it helps itself. There are many signs of nature's remarkable power to regenerate at Tahi, not least the return of a very special resident. So this is a SD card I've just pulled out from one of the cameras. As you can see here, we've got a kiwi. Kiwi are an indicator of the health of an ecosystem. Until the restoration work at Tahi, they had been regionally extinct for decades. Here we've got two following each other, so probably a pair, which is excellent. Now kiwi pairs here have one of the highest breeding and survival rates in any wild population in New Zealand. The return of the kiwi signals what nature can do when we restore complexity and let ecosystems recover. That looks like a juvenile as well. That's fantastic, yep, well done. That's great news. Yeah, it's amazing. We have shown that science-led strategic restoration works. Nature comes back. This is just one landscape. Imagine what's possible when we scale it. New Zealand's native ecosystems are the most resilient long-term method for storing carbon. Biodiversity is our greatest climate asset. Now imagine a New Zealand built on the true value of nature, where restoring ecosystems is also how we finance our future. That's the hope and the opportunity before us. The value of a forest is abundance of life, and the more forest we create, the more life we bring back.