On 15 December 2019, a firefighting operation in Australia’s Blue Mountains, New South Wales (NSW), went catastrophically wrong. Driven by erratic, gale-force winds, the back-burn – an effort to contain the monstrous Gospers Mountain wildfire that had been ignited by a lightning strike two months prior – jumped containment lines, sweeping through rural hamlets and scorching hectares of bush, farmland and apple orchards.

Also under fire was one of Australia’s natural treasures: the Blue Mountains Botanic Garden at Mount Tomah, a resplendent cool-climate garden featuring more than 6,000 species spread across 28 hectares of cultivated land, plus an additional 244 hectares of Unesco World Heritage-listed wilderness.

Despite valiant efforts of staff and the NSW Rural Fire Service, a quarter of the Botanic Garden was scorched. The garden’s most prized possessions, however, were saved: a collection of rare Wollemi pines, one of the oldest and most endangered plants on the planet.

The discovery of Wollemia nobilisis is considered one of the most remarkable botanical findings in recent decades

Meanwhile, north-west of the Botanic Garden in a deep, rugged canyon in the Wollemi National Park, the only known wild stands of Wollemi pines were also under threat from the seemingly unstoppable mega-fire as it relentlessly devoured more than half a million hectares of bushland.

The discovery of Wollemia nobilisis is considered one of the most remarkable botanical findings in recent decades. While bushwalking in the national park in 1994, NSW National Parks and Wildlife officer David Noble abseiled into a deep gorge and came across a grove of ancient conifer-like trees that were unlike anything he or scientists had ever seen before.

The tall, temperate rainforest species with bubbly, chocolate-coloured bark and multiple trunks is one of the world’s rarest trees; its evolutionary line – long thought to be extinct – dates back 200 million years to the Jurassic and Cretaceous periods, before the continent of Australia broke away from the Gondwana land mass. Although the species was common throughout eastern Australia until 40 million years ago, the lone relics that exist in this deep, damp canyon are, in effect, living fossils – miracle survivors of Australia’s ever-drying climate throughout the aeons and a rare link to the dinosaurs that may have snacked on their leaves.

The lone relics that exist in this deep, damp canyon are, in effect, living fossils

Since the tree’s discovery – described by then-director of Sydney’s Royal Botanic Garden Carrick Chambers as “the equivalent of finding a small dinosaur alive on Earth” – the Wollemi pine has experienced one of the most dramatic rebounds in ecological history, with successful propagation and plantings in both Australian botanic gardens and around the world. It has also been cultivated in several translocated bushland stands to ensure its long-term survival.

The wild population of Wollemi pines, however, is still considered highly endangered. The fewer than 100 mature trees are clustered around a 1km stretch of canyon in a highly confidential location inside the park. And while there is evidence that these trees have survived fire in the past, defending them from the coming onslaught was a top priority.

“We started to implement protection measures about three weeks [after the fire that started in late October],” explained Lisa Menke, Mudgee area manager of NSW National Parks and Wildlife Service and a member of the Wollemi Recovery Team. “We got a team of experts together and identified what we needed to do and actually started writing plans, knowing the trees were in the line of fire.”

The pines require a wet, shaded environment to survive, and since they were already suffering from drought, the first action was to install an irrigation system at their remote canyon site. To do this, a special team of remote-area firefighters were helicoptered in to descend into the pines’ secret location.

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“We were also working with the Rural Fire Service to flag what resources we might need in terms of aircraft, crew insertions, helicopter water-bucketing and whether we needed the large air tankers for retardant or gel drops,” Menke said. “We had a policy of no retardant in the actual wild sites, but we could use retardant outside the sites to try and slow the rate of progress towards the populations.”

Finally, at the end of January – more than a month after the Botanic Gardens at Mount Tomah burnt – the fire reached the wild Wollemis; and while some of the pines were charred by the blaze, the deterrents put in place by the remote fire-fighting team paid dividends, reducing the damage.

“I had many, many sleepless nights, watching the fire maps – it was terrifying,” said Dr Cathy Offord, principal research scientist at the Royal Botanic Garden Sydney. Offord, who has studied the Wollemi pine since its discovery 26 years ago, is a key member of the Wollemi Pine Recovery Team, which oversees the research and management of the pine. Over the years, her research has established the ancient tree as a global model for threatened species management.

The Wollemi pine is the poster boy for threatened species

“We do this sort of thing with other plants too, but they don’t get as much attention,” Offord said. “The Wollemi pine is the poster boy for threatened species – it’s the koala of plants, with a status above other threatened species because it tells the story about conservation and has captured people’s imaginations.”

NSW’s Minister for Energy and Environment Matt Kean described the firefighting operation to save the Wollemi pines as “an unprecedented environmental protection mission”. Since its success in January, focus has since shifted back to a stand of translocated (or “rewilded”) pines, located in the wilderness section of the Blue Mountains Botanic Garden, that was impacted by the fire in December.

“We had an experimental planting of Wollemi pines in the area of bushland that was burnt out,” said Brett Summerell, chief botanist at the Royal Botanic Garden Sydney. “This was the first time we’ve been able to observe what happens to the Wollemi pine when they are burnt in the wild. Most of the trees affected by the fire at the gardens had been grown in our nurseries – they were around eight years old. Some were starting to produce cones and seed.”

“I don’t think all of them will come back,” Summerell added. “The impact of a fire is always greater on a younger tree than on old trees that have a resilience.”

Being able to observe the impacts of fire, as well as climate change and other major threats – including an exotic root-rot pathogen called Phytophthora cinnamomi – on cultivated and translocated Wollemi pine populations has allowed researchers like Summerell and Offord to plan for the tree’s future.

“One of the management strategies for conserving wild species is to bring those plants into cultivation, like in a zoo, and to put them into other areas to see if they can survive there, doing what we call ‘assisted migration’,” Offord said.

Plant lovers and those curious to see what this fascinating dinosaur tree looks like can see them in Sydney’s three Botanic Gardens and Centennial Parklands, and the Royal Botanic Gardens in Melbourne. Interestingly, however, some of the healthiest examples of Wollemi pines are found in the Royal Botanic Gardens, Kew, just outside London, where the weather is cooler and moister than the Australian bushland.

“I think that very much reflects the Wollemi pine’s origin being in a cool, temperate area with a lot of moisture and low sunlight, because England has less sunlight,” Offord said. “The sunlight is very intense in Australia – it’s a bit of a fish out of water here.”

It’s a dinosaur plant that still exists

With cultivated Wollemi pines now growing successfully around the world, the Royal Botanic Garden Sydney has introduced a citizen science project called “I Spy a Wollemi Pine”, inviting members of the public to complete a survey whenever they come across one of the prehistoric trees.

“That’s been a really important tenet in the whole programme, to make people feel like they are stewards of this species and that they can make a difference,” Offord explained. “They can learn about it – it’s part of the mythology now of the Wollemi pine. It’s a dinosaur plant that still exists, that you can touch and feel and grow it; and meanwhile, you can still contribute to its conservation.”

For the time being, however, the wild population of Wollemi pines in the national park remains strictly off limits, with the public encouraged to keep their distance.

“If people want to experience the Wollemi pine, go to the Botanic Gardens, have a look at them there and recognise them and value them for their uniqueness,” Menke said. “The Wollemi pine is really special. Our best protection is to stay away from them in the wild as much as possible.”

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