23 October 2023

Naming plants to save them

It’s been 35 years since I became a scientist. The world has changed and so has science, and yet plant naming remains at the very core of everything we’re trying to achieve. This is why.

A waterlily leaf viewed from below and from above

The great inventor of scientific plant names, Carl Linnaeus once wrote – 'If you don't know the names, your knowledge gets lost.'

I didn’t hear this quote until the early days of my career as a plant scientist, but my love for plants goes back long before this. At age seven my great aunt gifted me a pond to grow waterlilies, my favourite plants in their garden back home in Belgium. The waterlilies are still alive and with me today, four decades later. 

I wanted to learn the names of all the garden plants and those I saw out and about as a child. Knowing about as many as I could fascinated me as I grew into a teenager. 

By the time I was entering my late school years and university – the 1980s – things had started to change. Not my love for plants, but a global awareness of how they were getting on. 

On TV we saw celebrities like Sting journey to the Amazon rainforest and bring knowledge of habitat destruction into the public consciousness for the first time. In the background, modern conservation was beginning to emerge. 

A sepia photo from the late 70s shows a Kew researcher as a child examining some garden plants
A young Rafaël Govaerts (centre) exploring the world of garden plants with his great aunt (right) - the source of his first waterlilies - and her half brother (left). © Rafaël Govaerts


Already as a teenager I made the pilgrimage to Kew Gardens to do my own research. I was surrounded by the world’s experts in every plant group you can imagine, each of them attempting to share their lifetimes of knowledge and understand what we might be losing as the world changed. 

This was still pre-internet. Information was harder to share. Too often I would witness the huge tragedy of experts retiring or passing away, taking their years of accumulated knowledge with them. 

Early conservation at that time was focused around what we knew well – which was largely the plants found in Western nations that had been studied in detail for centuries. Back then, science was largely blind to the scale of nature in what we consider the world’s ‘biodiversity hotspots’ today. 

It’s a simple fact: you cannot save what you do not know and understand. 

Reports on the increase in plant extinction touched me deeply. Surely, I could not allow my beloved plants to become extinct. So I came up with a plan – I will get a list of all the plants in the world, find out which ones are very rare and then make sure action is taken to prevent them from going extinct. 

I travelled to the botanic garden in Brussels in the hope of finding a list of all the plants in the world that we could use as a starting point. 

'There is no such list,' they told me. 

'Fine,' I thought. 'I’ll make it myself'. 

Rafaël Govaerts stands amongst many different plants and a giant tortoise
Rafaël's travels to the Galapagos bring encounters with endemic animals like giant tortoises but bring a shock when it comes to plants - every single species in this photo is invasive to the Galapagos © Rafaël Govaerts

The great checklist 

If I could build a checklist of all the plant names in the world and group them together under their correct name, perhaps others would be able to use this to save them.

I started in botanical libraries, digging through records. Priorities arose as taxonomists with specialist knowledge took interest, curious about why a student was digging through every plant name he could find. 

By the late 90s I had begun working at Kew and collaborating with Botanic Gardens Conservation International (BGCI). 

At Kew I built lists of plant families, like the oak and magnolia families, for which BGCI experts would then carry out Red-List conservation assessments, building the first ever expert-reviewed lists on which real conservation action could be built. 

We began to form a checklist using the structure of Kew’s oldest project – the International Plant Names Index (IPNI), which started in the late 1880s as part of Charles Darwin’s legacy. The race against time started to become real, both in the sense of losing species to extinction, and losing human knowledge. 

By 2003, we had achieved a couple of major milestones, finishing the list of all monocots – these are grasses and grass like plants. On the other hand, before we’d even had the chance to begin on including them in the list, the untimely passing of the world-leading expert on the curare plant family (Menispermaceae) set work on these plants back years. 

We had to be quicker to succeed in building “The World Checklist of Vascular Plants”.

A pile of acorns
Acorns belonging to a tree of the oak family, one of the first to be incorporated into the growing World Checklist of Vascular Plants © RBG Kew
Dioscoreophyllum cumminsii flowers splitting off from a long inflorescence
Dioscoreophyllum cumminsii belonging to the family Menispermaceae, a group of plants much harder to build into the checklist with years of knowledge lost. © RBG Kew

Why do we need it?

Each plant name became the centre of a web of the published data and research related to that plant. Within Kew, this resulted in the creation of the hugely successful Plants of the World Online (POWO).

With each name in the checklist, we included all the countries where each plant species was known to occur in the wild. A world map of entire plant groups began to take shape. 

We also linked the findings of new DNA studies through the Plant and Fungal Tree of Life (PAFTOL), paving the way for massive research projects that are still unfolding now.

After 30 years of work, we finally completed the World Checklist of Vascular Plants in its current form. It’s now updated continuously as new species are named and scientific advances are published. 

In the State of the World’s Plants and Fungi 2023 report, we see how it has facilitated new research that never before could have been achieved. 

With the checklist data, we’re learning how we can increase the value of new protected areas by prioritising plants that carry out different roles within a habitat, or that are distantly related in the evolutionary tree. 

The checklist has also been used to identify 'darkspots', parts of the planet harbouring unknown biodiversity that we urgently need to build a better understanding of. 

A hillside part exposed to the sun, part in shadow is overlaid with the text "32 global plant diversity darkspots have been identified, highlighting critical knowledge gaps
A core message of the 2023 State of the World's Plants and Fungi report: 32 global darkspots that are key knowledge gaps, were identified thanks to the World Checklist of Vascular Plants
Two scientists pose for a photo
Celebrating the release of the completed World Checklist of Vascular Plants with collaborators. © Rafaël Govaerts

A database for all databases

I’m incredibly proud that the World Checklist of Vascular Plants has made an assortment of other open access data resources possible too.

The Medicinal Plant Names Services database that lists plants based on their uses in modern and traditional medicine is built from the World Checklist. So too is iNaturalist, a wildlife surveying tool that allows anyone to become a researcher. 

I’ve witnessed important scientific tools like the Global Biodiversity Information Facility (GBIF) and Catalogue of Life (CoL) pop up with the help of this one central checklist. 

We work closely and collaborate with other major sources of plant information too, such as the World Flora Online project and the Leipzig Catalogue of Vascular Plants, to advance, innovate and share information. 

The POWO landing page features a searchbox and the text Visitors to the Plants of the World Online are greeted with an invitation to use one of the most valuable plant science resources in existence.
Visitors to the Plants of the World Online are greeted with an invitation to use one of the most valuable plant science resources in existence.

A world checklist for everyone

The World Checklist of Vascular Plants is an invaluable resource, one that is free to use for anyone, anywhere. 

For the years ahead, I imagine all of the world’s plant scientists linking their data, understanding and knowledge to form a huge global collaboration. This would be a powerful tool to fight biodiversity loss and extinction.  

The potential questions we can answer with this resource are infinite, and we’ve only just begun to scratch to surface. I could not have dreamed of today’s research questions 30 years ago, when I was starting out.  

The seven year old within me is happy that he can now look up the name and information of every single plant in his back garden. Now this same plant names resource can help accelerate global conservation when it has never been more important.

The back of a head of a researcher looking at Kew's Plants of the World Online portal on a computer screen

The World Checklist of Vascular Plants is free to use by all

You can access this invaluable resource in the form of the Plants of the World Online resource

A forest landscape has light shining through gaps in the canopy. Leaf litter covers the floor.

The State of the World's Plants and Fungi Report

Read more about why names matter in the latest assessment of global plant and fungi diversity