From the archives: Arbor Day, established to inspire people to plant, nurture and celebrate trees, is on June 5 so listener.co.nz revisits some of the NZ Listener’s recent stories which aim to get us planting, nurturing and celebrating trees. In this 2020 story, Sally Blundell explores why our life-supporting and brain-function-boosting trees are under siege.
It is an enchanted elven forest, says Australian ecologist Mark Graham, largely unchanged over tens of millions of years. “So we are back to the dawn of the evolution of flowering plants and songbirds, back to the time of the dinosaurs.”
A member of the Nature Conservation Council, Graham owns a private conservation reserve on the Dorrigo Plateau, part of the Gondwana Rainforests of Australia stretching across 366,500 hectares across New South Wales and Queensland. These rainforests are some of the oldest on the planet, one of the few remnants of the supercontinent of Gondwana that broke up about 180 million years ago.
“The songbirds in this part of the world are some of the most ancient songbirds on the planet – listening to the dawn chorus in this forest is like having a window back in time.”
Now, instead of songbirds, he hears the roar of fire just 500 metres from his home. “I have never heard anything like it. It is like Mother Nature is so angry she is growling with the deepest, most guttural tones.”
These rainforests, a Unesco World Heritage site, are not meant to burn. They have been wet for tens of millions of years. But burning they are. As of two weeks ago, 247,000ha have been scorched. Graham reckons that number will already have increased by some tens of thousands of hectares since then. Strong winds and low humidity make firefighting difficult and dangerous. A thunderstorm is brewing, a downpour is likely, “but we need 200mm of rainfall to solve the problem and we are unlikely to get that for some time.”
The damage caused by fire in the Gondwana Rainforests has been described as a “global tragedy”.
Birds can fly elsewhere but there are few refuges for the ancient fauna species that live deep in wet leaf litter. “Frogs, ancient lizards and snakes have no capacity to survive fire. They just get cooked. Some plant species have the capacity to regrow but some of the delicate species that require permanent moisture, like the ferns, will probably die out.”
This is not part of an age-old cyclic pattern of wild fires. This is drought, wind, high temperatures. Climate change?
“Absolutely. These fires are off the charts. There is no historical reference point, we are in absolutely uncharted territory in terms of the extent of country that has burnt, the severity of the fire, the range of ecosystems affected, the altitudinal range of the fire, the number of houses lost.”
Across New South Wales, out of a total of 1.9 million hectares of national park land, 800,000ha have succumbed to fire since July. Just last month smoke from bushfires clogged the air over Sydney, setting off smoke alarms, cancelling sports events, delaying ferry services and flights in and out of the city and triggering health warnings. No one can deny, NSW environment minister Matt Kean told a Smart Energy Summit in Sydney, that climate change is to blame for the bushfires and the historic levels of smoke blanketing the city. “If this is not a catalyst for change, then I don’t know what is.” (Not everyone agrees – on ABC radio station, deputy prime minister Michael McCormack described those linking the bushfires to climate change as “raving inner-city lunatics”).
Australia is just one of a rash of red spots on the Global Fire Watch map. From Lebanon to California and France to Siberia - one of the coldest places on Earth - fires have been destroying forests. Data from the satellite-driven Sentinel-3 World Fire Atlas recorded 79,000 fires in August 2019 compared to just over 16,000 fires detected during the same period last year. Of these, almost half were in Asia, around 28% in South America, 16% in Africa, and the remaining in North America, Europe and Oceania.
A recent European Commission report shows wildfires destroyed nearly 178,000ha of forests and land in the EU last year. While this is less than the area burnt in 2017, more countries than ever suffered from large fires and, as more people choose to live closer to – or in – wilderness areas, more houses are being lost.
Forests, said outgoing EU environment commissioner Karmenu Vella, are our life-support system, hosting 80% of the Earth’s biodiversity and standing at the frontline in reducing climate change. “But today, like never before, they are under severe threat. 800 football fields of forest are lost every hour, and devastating fires are raging around the world.”
The extent of the relationship between forest fires and climate change in still unclear. Changing sea surface temperatures resulting from El Niño or La Niña events cause shifts in wind patterns, cloud cover, atmospheric temperature and precipitation which in turn affect temperatures and other conditions on land. It is a complicated give-and-take between the atmosphere and ocean but recent research has found ENSO (the collective name for the ocean-warming El Niño weather pattern and its complementary ocean-cooling La Niña patterns) to exacerbate the worst of the climate crisis. A recent study published last year in Geophysical Research Letters, the journal of the American Geophysical Union, used coral records from the past 7,000 years to show that, since humans started burning fossil fuels on an industrial scale, heat waves, wildfires, droughts, flooding and violent storms associated with El Niño events have grown markedly worse. The prospect for larger ENSO extremes under continued greenhouse forcing, the authors concluded, “greatly increases the societal and ecological vulnerabilities to climate change.”
While most wildfires are classified as natural disasters – a mutable term in relation to climate change – the majority are caused by direct human action: unattended campfires, discarded cigarettes, arson and deforestation for agriculture. A surge of fires in the Brazilian Amazon, over 70,000 this year, has been blamed on illegal land clearances for cattle ranches. In Indonesia, over three-quarters of fires last year are said to have been set to clear land for palm oil plantations (Indonesia supplies just over half of the world’s palm oil). Indonesia’s ranking as the third-largest global emitter of greenhouse gasses, the World Wildlife Fund reports, is due to the country’s high deforestation rate.
When humans first arrived in New Zealand, forests covered about 80% of New Zealand. By the end of the last century, this had been whittled down to just over a quarter, concentrated in mountainous and hilly areas on the conservation estate or in remnant patches held on public reserves or covenanted on private land.
Even within these areas, pests – stoats, rats, feral goats, deer and possums – and diseases such as kauri dieback and myrtle rust are all taking their toll. Wilding pines, like the Christmas conifers currently wilting in their aspirin infusions, are changing our landscapes and dominating out native forests.
As the pressure on the world’s forests mounts up, so too do arguments for their survival. Forests play a critical role in mitigating climate change. They purify the water and air, absorb carbon and cool the environment (through a process of water evaporation or evapotranspiration). They provide jobs, food and natural habitat – 80% of the world’s land-based species, including elephants and rhinos, live in forests.
They also calm our shattered nerves. Books, articles and medical journals are increasingly extolling the virtues of time spent in forests to reduce depression and anxiety, think more clearly and maintain physical wellbeing. The ancient Japanese practice of shinrin-yoku or “forest bathing” is now finding its way into self-help manuals and science journals, as new research finds those who spend time in forests have less stress and improved mood, creativity, mental health and immune and cognitive function (the Royal Botanic Garden in Melbourne now offers forest therapy for $36 a pop).
In Washington DC, journalist Florence Williams, a fellow at the Center for Humans and Nature in Chicago and author of The Nature Fix, has been promoting the importance of time spent in wild places, even the local city park.
“Humans have an innate association with these landscapes,” she says from her home close to one of Washington’s many city parks. “Even subconsciously, our brains and perceptual systems understand landscapes and feel comfortable in them. City planners need to recognise this as a priority for the health of our communities and our people. We know [anxiety and other mental health problems] are worse in cities and we know access to nature can calm our nervous systems and those parts of the brain that get overactive in the city.”
For her book, she travelled to South Korea, Japan, Scotland and Finland, looking at the range of new and old programmes aimed at meeting our apparently deep-seated need for a dose of intense nature. Most of them take little effort. You walk into the forest – no cellphone, no playlist, no traffic. You listen to the birds, watch the movement of light on the leaves, feel the coolness of the air, pause, breathe – deeply. Back at home, Williams trawled through a wealth of medical data. Increasingly, she says, scientists are quantifying nature’s effects on mood and wellbeing, “and on our ability to think to remember things, to plan, to create, to daydream and to focus”.
Studies show time spent in forests reduces concentrations of the stress hormone cortisol, lowers pulse rate and blood pressure, lessens levels of hostility and depression and, for children in particular, improves fitness and self-confidence. This it does on a number of sensory levels. Aerosols in evergreen forests have been found to act as mild sedatives and stimulate respiration; the sounds of water and birdsong improve mood and alertness, says Williams, and the colours and patterns of natural treed landscapes, as any Romantic poet would attest, are calming to the eye. Even videos of nature have been found to relieve stress and mental health and behavioural issues in prison inmates.
There were times when she was sceptical, says Williams, but it was a pleasure and revelation “to realise how our surroundings can help prevent physical and mental problems.” She recommends a goal of five hours a month in nature (about two 30- 40-minute periods a week) to counteract what she describes as an “epidemic” of dislocation from the outdoors – an epidemic that is damaging to our health and to that of the environment.
“If we recognise we need these ecosystems for our own health, it is yet another argument in support of conservation, because we are more inclined to protect something if we see more value in it. It is after we establish a true bond with these places and an understanding of how connected we are that we can really start to care about them.”
Over the past decade, a rash of new books have been hammering home the importance of trees. In The Man Who Planted Trees, New York Times journalist Jim Robbins tells the true story of a man on a mission to reforest the world by cloning the oldest, largest and most resilient trees. US scientist Daniel Chamovitz demonstrates how plants respond to touch, sound, smell, sight and even memory in What A Plant Knows. Richard Powers’ mythic The Overstory, winner of the 2019 Pulitzer Prize in fiction, has trees as revered ancestors – slow, interconnected, resourceful.
In 2016 German forester Peter Wohlleben put scientists into a spin with his hugely popular The Hidden Life of Trees, in which he argues that, to better protect our forests, we need to acknowledge that trees have vibrant, inner lives not so different from our own. They thrive in families, he says.
They form social networks, care for each other and send out signals about drought, disease or encroaching herbivores. Such comments are supported by recent research into the way trees communicate with each other, above and below ground. Scientists have found trees do “share” water and nutrients through microscopic networks of fungal filaments (Wohlleben calls it the “wood-wide web”). It is a symbiotic relationship. The fungi feed on the sugar that trees photosynthesise from sunlight; the trees absorb the nitrogen, phosphorus and other mineral nutrients taken up from the soil by fungi. Research at the University of Lausanne in Switzerland into the chemical, hormonal and slow-pulsing electrical signals emitted by trees, reported in the Smithsonian last year, has identified a voltage-based signalling system “that appears strikingly similar to animal nervous systems”.
The Hidden Life of Trees was a hit. It sold more than 800,000 copies in Germany and topped best-seller lists in 11 other countries. But his anthropomorphic language infuriated others. Wohlleben talks of “mother trees” feeding their saplings with liquid sugar, of trees forming “friendships” and nourishing sick individuals. Much like a herd of elephants, he writes, trees “look after their own, and they help their sick and weak back up onto their feet”.
In 2017, two German scientists launched an online petition to challenge these claims. The petition, titled in English “Even in the forest, we want facts instead of fairy tales”, said the book promotes “a very unrealistic understanding of forest ecology”. In the long term, they said, “the environment in general and forests in particular will not be helped by the sort of unenlightened thinking promoted by the hidden reality of this book.”
But if the semantics are questionable, the driver behind Wohlleben’s book is not. If we recognise trees’ “emotional lives and needs”, he writes, “we will stop seeing forests as timber factories, and understand how forests can serve as oases of respite and recovery.”
The current “anthropogenic ecological crisis” also lies behind Plants as Persons by botanist Matthew Hall, now associate director of research services at Victoria University. In this book he calls for a more harmonious relationship between humans and nature to avoid the “banal, unthinking scorched-earth policy” that we have inflicted on our plants and on planet. “We transformed the planet for our end,” he says. “It is that impetus, to exert dominion over the land, as Genesis says, that has led us to this point. Part of the solution is to undermine that.”
Acknowledging plant sentience, he argues, is a start.
His book covers the extremes of Jainism, in which plants are recognised as sentient beings, and, at the other end, the “total violence” that results in widespread destruction of natural habitats. “Somewhere in the middle we can recognise violence and act in a way to minimise that. Of course, we still have to use plants for food, shelter, medicine, clothing but our first step is to recognise that we are taking a life. A key feature of many indigenous cultures is that the harm done to individual plants is not ignored or backgrounded.”
In his new book, The Imagination of Plants, he plumbs the world’s religions and mythic traditions to expose the many examples of a deep-seated respect for – and kinship with – plants. It is a curious read, amply illustrated and supported by extracts from various myths and manuscripts. It includes stories of gods creating plants and humans (Māori trace their whakapapa back to Ranginui and Papatūānuku, from whom the forests then humans were created); of first humans fashioned from wood (elm in Nordic countries, broom in Wales, ash in early Greece); of tree worship (including the many trees associated with Buddha); of metamorphosis from plant into human form; of trees that speak or weep. A new wave of contemporary tree-loving paganism – Hall applauds Prince Charles’s habit of wishing every tree he plants the very best – suggests a reawakening “of some kind of existential need to reconnect with these habitats that we are losing”,
Like Wohlleben’s loving, nurturing, grieving trees, calls to recognise plant sentience and reconsider the “moral standing” of plants are an easy target for exasperation, derision and questions – what, for example, do we even mean by sentience? Or personhood? Or volition? But as fires continue to burn and trees continue to be felled, a growing recognition of our reliance on forests is already prompting a wave of tree-planting and forest restoration activities. Even the recognition of the forested land of Te Urewera, now holding the same “rights, powers, duties and liabilities of a legal person” under the Te Urewera Act of 2014 – can be seen as a change in the value we place on our forests.
“I don’t think you need that spiritual connection to appreciate and value landscapes and feel comfortable in them,” says Williams. “I don’t want nature to seem precious and inaccessible – I find nature very accessible. It can be the shrub in the back yard, it can be the sunset, it can be a national park. But it is also about attentiveness. I try to encourage some practical ideas for how to open your senses and be present and mindful in the outdoors – that is where research shows you get the benefits, by paying attention.”
Strange tree facts
Climate threat
- Wide, squat, with a frantic Suessian crown, the baobab tree is part and portly parcel of the sub-Saharan Africa landscape. The trunks are often hollow and have been used as homes, shops, meeting places and, in South Africa’s Limpopo Province, a cocktail bar. But over the past dozen years, four of the 13 largest, and probably oldest, trees have died and more are ailing. A report, published in Nature Plants, describes 2000-year-old baobab (Adansonia digitate) trees rotting and splitting, the result, the researchers suggest, of climate-change-fuelled drought.
Up the wooden staircase
- As a building material, wood is light, flexible, good at withstanding earthquakes and a far cleaner alternative to greenhouse-gas emitting concrete. And it is going up in the world. At 85.4m, the recently completed Mjøsa Tower in Brumunddal, Norway, has replaced a 53m dormitory at the University of British Columbia, Canada, as the world’s tallest timber tower. Perhaps not for long. A 244m, 80-storey residential “plyscraper” has been proposed in Chicago, while Japanese timber company Sumitoto plans a 350m tower made of 90% wood and 10% steel.
Altogether now
- Japan’s cherry blossom viewing season, known as hanami, is short, spectacular and weirdly in sync. The flowers of Somei Yoshino, considered the most beautiful of cherry blossoms, all bloom at the same time in a storm of pink. Why? Flowering cherries are infertile – they do not fruit. But although many have been propagated through grafting, the use of cloning has resulted in Somei Yoshino trees being genetically identical, allowing their blossoms to bloom and fall at once.
Dip and stretch
- A group of 400 pine trees planted outside Nowe Czarnowo, Poland, in about 1930 is considered one of the world’s most mysterious forests. Known as the Crooked Forest, the trees are bent at 90° just above their base. From the point after the bend, the trunks rise upwards into the shape of the letter “c”. One theory is that the pines were damaged by passing tanks during World War II, literally bending the young trees groundwards.
Room with a view
- Between December 1997 and December 1999, American environmental activist Julia “Butterfly” Hill spent 738 days on two 1.8m by 1.8m platforms in the branches of a 55m, 1500-year-old California redwood called Luna, to save it from the Pacific Lumber Company. With a single-burner propane stove, sleeping bag, solar-powered cellphone and ropes to hoist supplies, she endured freezing rains, wild winds and a 10-day siege by company security guards. She came down only when the timber company agreed to preserve Luna and all trees within a 61m buffer zone.
All by myself
- New Zealand is known for its forested valleys and mountain flanks but is also home to the world’s loneliest tree. The Sitka spruce, a Northern Hemisphere native, stands in stunted isolation in a wind-battered cove on subantarctic Campbell Island, more than 273km from the nearest trees on the Auckland Islands. It was planted about 1900 by then-governor, Lord Ranfurly.
Old and stunted
- A pair of short, gnarly Great Basin bristlecone pines in California’s White Mountains are considered the oldest trees in the world. About 5000 years in age, they are as old as Troy, bronze tools and wheeled vehicles.
This story first appeared in the NZ Listener’s January 11 - 17, 2020 edition.
