We need to appreciate trees not only for their beauty and as providers of welcome shade but also for their vital climate role – yet time is fast running out.
Iwi would have appreciated this tree, and Captain Cook would’ve seen those same towering branches as he cruised the Waiheke coastline in 1769. It’s remarkable to think what this tree has lived through, how many other people have leant against it, drifted their hands across its trunk and sought its shelter. This tree, all trees, are natural historians, keepers of our past – but they are also vital guardians of our future.
The iconic pōhutukawa is a beacon of our Kiwi summer. The most prized real estate on the beach, these magnificent trees signal us with their red flags, welcoming us into their shelter. In those moments – safe under their huge arms – we are grateful for trees; we see their value and marvel at their size. Yet, when all is packed up and the beach left behind for the day, the value of these magnificent providers seems forgotten.
We have taken our trees for granted. We have expected them to provide for us, to give us shelter and shade, yet have given very little back. We have used and abused them. But we need them, desperately. As our summers get hotter, relief from the scorching heat will become paramount. And yet shade is the simplest of the many ways trees help reduce a rising climate. These willing workers revolutionise our existence every day, with every second they stand.
Trees cool the air through a process called transpiration. In the same way we sweat to cool down, transpiration draws water up through the soil by the trees’ roots, which then evaporates through the leaves – cooling the atmosphere around it. Perhaps the most well-understood role that trees play is in balancing carbon dioxide with oxygen. Heat from the sun or cities becomes trapped close to the Earth by the carbon dioxide in the atmosphere and global temperatures rise. If we have any hope of slowing this process, which is making our home uninhabitable, we must plant more trees. We must have more trees working to extract carbon from the atmosphere.
Of course, it’s not just us that these benefactors work for. Trees support multiple ecosystems and life cycles. Imagine an Aotearoa without our iconic birds. We already have a shamefully long list of threatened species numbering in their thousands.
About 20 years ago, the Crown Research Institute that I chaired, Landcare Research, built a towering structure over the tōtara forests of Ōkārito, in Westland; a man-made scaffold that extended above the treetops and allowed us to observe every level of the canopy. A healthy forest canopy teems with life; we saw untold species of insect and bird, with flocks of kākāriki bursting through the top into the sunshine. It was a reminder that, as ground dwellers, we miss so much, but it’s these ancient communities that we must preserve.
Although my doctor has exhausted all the options, we as a nation have not exhausted ours when it comes to saving these species. This is a crisis. Time is running out for the treasures of nature that we love, and it is worth using every last breath, all of our collective energy, to save our land and secure our future.
We must make change. We must move away from the 1990s economic model that valued pines over native planting, resulting in disasters such as the one that sent a soup of mud and pine slash into Tologa Bay’s community in 2018. We must rethink investment models that have favoured dairy conversions, transforming forests into farms that expose fragile pumice soils to erosion and cows to unrelenting heat. The connection between trees and animal welfare seems obvious to too few.
Two years ago, with others, I started the Aotearoa Circle, a group of public- and private-sector leaders committed to halting the decline of New Zealand’s natural capital. It came on the coat-tails of the Environment Aotearoa state of the environment report, which showed all our stocks of natural capital – soils, fresh water, the climate, biodiversity and the marine environment – were in decline. It is reasonable to predict that in 100-200 years, our biological economy will be bankrupt. It’s a horrific legacy to bequeath to future generations. The Aotearoa Circle aims to shift the levers of investment from environmentally unsustainable extractive industries to intergenerational protection of the pillars of natural capital. And guess what the secret to preserving New Zealand’s natural capital is? Trees.
As I contemplate my own demise, I return often in my mind to my favourite tree – that pūriri holding court on Waiheke Island. I consider this magnificent being, by far the oldest living thing I know, holding in its branches the diversity of nature – from the plump, cheeky kererū to the magnificent pūriri moth whose lifeblood is the tree’s juicy sap.
Imagine that this pūriri could one day be the last lonely cradle of the kererū and pūriri moth. For them, like me, like so much of New Zealand’s biodiversity, time is running out. I can tell you in plain English that I am dying. And although the environment might speak its own language, its cries cannot be misunderstood. We know what is happening, we know what we must do – now, we must simply do it.
This article was first published in the March 7, 2020 issue of the New Zealand Listener.