The Scottish plant hunters unravelling the secrets of the jungle

Hacking through a tropical forest for a tiny flower has echoes of the golden era of intrepid plant hunters - such as Scottish botanist George Forrest who risked life and limb to become one of the most prolific plant collectors ever. 

Yet thousands of miles away in his base at Royal Botanic Garden Edinburgh, his colleague Dr Mark Hughes, was also on his own thrilling plant hunt.

Unlike Dr Poulsen, he wouldn’t need to risk it all for a flower. Instead, it would be a Facebook post that would lead him to a new species.

Dr Poulsen of Royal Botanic Garden Edinburgh, was searching for rare ginger plants in Papua New Guinea (Image: RBGE)

Photographs of a tiny Begonia from the Leparada District of Arunachal Pradesh in North East India – known as the “land of dawn lit mountains” - had been uploaded by a local government scientist and plant enthusiast.

The location is regarded as a paradise for botanists with forest covering 80% of its area harbouring a huge diversity of habitats and rich in flora. But, as with so many locations, it is also under increasing pressure from development.

Dr Hughes, an expert in Begonias with countless field trips behind him, suspected he was staring at a new, previously unrecorded species.

Messages flew between his desk in Edinburgh and Dr Dipankar Borah, of Kaliabor College in Assam. Samples of the tiny pink flowering Begonia were retrieved by a local team and working together but miles apart, they confirmed it to be a new species.

The two episodes – one a Victorian-style epic trek through wild jungle, the other a far more sedate example of ‘fieldwork by proxy’ - illustrate the Garden’s double-sided  approach to 21st century plant hunting as it strives to record and support biodiversity across huge areas of southeast Asia.

Red ginger seed pods and seeds retrieved by Dr Poulsen which have now produced plants at RBGE (Image: RBGE)

The work, spanning different countries, languages and cultures, from Papua New Guinea with its host of exotic gingers to Borneo where vast swathes of forest have been lost, is particularly time sensitive. Deforestation, mining, logging work and palm oil production is threatening large areas, some of which may harbour previously unrecorded species and others which could benefit from further research.

Climate change is compounding the threat, sparking bushfires and El Niño-induced droughts across a region that boasts 15% of the world’s tropical forests, has four globally important biodiversity hotspots, and unique habitats.

It’s led to RBGE's renewed push in the area with Herbarium-based work and a team of five in Edinburgh led by Dr Hughes, alongside the more traditional field work such as that carried out by gingers expert Dr Poulsen in remote areas of Papua New Guinea.

Dr Poulsen, ginger expert at RBGE during his expedition to find rare plants in Papua New Guinea (Image: RBGE)

Over the past year, new collaborations have been forged with experts in locations including India, Papua New Guinea and Malaysia, aimed at better understanding the region’s plant diversity and how it is threatened.

One aims to list every plant from across southeast Asia for the first time. A massive job, it is not even clear how many species there are: estimates range from 25,000 to 45,000, perhaps 50,000.

The international collaborations mean modern plant hunters don't even have to leave home - a far cry from predecessors such as Falkirk-born George Forrest, whose early 20th century Chinese expeditions boosted RBGE collections. 

During one trip he spent weeks hiding from local rebels intent on killing him, so enraged were they by increasing Western influence in their area at that time.

Falkirk-born plant hunter George Forrest risked his life in the hunt for plants in China (Image: Contributed)

Perthshire-born 19th century plant hunter David Douglas's adventures were even more extreme. A larger than life character, he survived a grizzly bear attack, nearly drowned in a whirlpool and, having become snow-blinded during a mountain trek in search of plants, stumbled into a  cattle pit and was gored to death by a bull.

Technology means today's efforts are far less bruising: through collaboration with his Indian counterpart, Dr Hughes,  RBGE’s Taxonomy Research Leader (Southeast Asia), helped confirm the discovery of three previously unrecorded begonias and new sightings for others, all from his desk.

Along with the ‘Facebook’ begonia, Begonia egamii – named in honour of Egam Basar, the government official who first spotted it -  working remotely with Indian colleagues led to the discovery of Begonia ziroensis, with delicate white blooms and found the Ziro Valley, a UNESCO World Heritage Site in Arunachal Pradesh.

And Begonia tripurensis, found clinging to a cliff in the Tripura, India’s third smallest state where forests and vegetation have been badly impacted by expanding rubber and teak monocultures.

He says the Garden’s renewed focus on southeast Asia builds on its data from the 1960s while also aiming to grow the area’s own scientists.

“It is a vast region with numerous riches but under enormous challenges particularly from palm oil plantations and deforestation,” he adds.

Dr Mark Hughes discovered new species of Begonia from his desk at Royal Botanic Garden Edinburgh (Image: Royal Botanic Garden Edinburgh)

“During the pandemic we were remote working and thought we could collaborate and support fantastic young scientists in the region who could go out on location and share data.

“It is like a knowledge exchange rather than in old colonial terms; it is collaboration with equals and sharing knowledge.”

It’s hoped the newly found Begonias and the red flowering ginger, raised from seeds collected by Dr Poulsen from Papua New Guinea, will be displayed when the RBGE Glasshouses reopen following major restoration.

Dr Poulsen worked with a team from PNG Forest Research Institute in search of Alpinia fusiformis.  It is among many species already recorded but which it's thought may have a different family tree than suspected once revisited using new technology to unravel its DNA.

Having navigated waters infested with crocodiles, torrential rain, illness and flight delays, he finally found it.

While it might sound extreme lengths to go to, Dr Poulsen says the effort is vital to establish the plants' full taxonomy and to help protect them in the future.

“It is one thing giving names to species, it’s another for it to have conservation status – it is like giving them a voice,” he adds.

“Who knows what is hiding in little valleys that are difficult to access? We are just starting to learn what species are there.”

RBGE’s southeast Asia work has been rejuvenated in the past year as a result of support from players of Peoples Postcode Lottery (PPL).

In addition to finding new species, the team is also involved in Darwin Initiative-funded project to rehabilitate forests in Borneo decimated by illegal mining and palm oil production.

Ginger plant seeds retrieved from Papua New Guinea by Dr Axel Poulsen have produced seedlings at Edinburgh's botanic garden (Image: RBGE)

One challenge for its team member Dr Peter Wilkie, is trying to figure out which trees to plant:  Borneo has more than 10,000 species.

Another project involves University of Philippines student Jeffrey Mancera who will meticulously scour Herbarium collections at RBGE and compare plant records with historic weather data to spot links between climate and mass flowering and fruiting of tropical trees in Southeast Asia.

“Tropical trees sense the world differently to trees here - the tropics don’t have the same seasons as we do yet they still need to flower en masse in order to overwhelm the seed predators," says Dr Hughes.

“People tell us it’s now harder to predict flowering because these seed patterns are changing.

“This project is about using the knowledge of the past to predict the future.”

Meanwhile, Dr Poulsen is set for another expedition. This time it is to the jungles of Borneo, where deforestation has happened on a massive scale: 50% of forest has been lost since the 1970s.

It's thought 50% of the Bornean rainforest was lost between 1973 and 2015

While there are obvious parallels between his work and Edwardian and Victorian plant hunters, he insists the modern approach is of collaboration and diplomacy.

“I have to be out in field, climbing around volcanoes. How can we manage natural resources if we don’t know what is there?,” he says.

“But somewhere like Papua New Guinea is not only botanically diverse, it’s a country of 800 languages, every valley and place within it has a different heritage.

“It’s all very good having a permit from authorities in the capital but there are different rules in the countryside and the islands.

“We have to respect and be accepted by the community.

“We have to explain we have not come to look for a new drug to make them rich, and we’re not there to make money.

“But it’s better for humankind to understand how many species are there."

He adds:  “It’s not just me jumping out of the helicopter with a tropical helmet and bush knife hacking my way through.

“We have to make friends.”