More than three-quarters of undescribed plant species are already threatened with extinction, according to a new report by the Royal Botanic Gardens, Kew.
And for known flowering plants, the picture is also bleak – 45% of them are estimated to be threatened with extinction.
Kew’s report gives a global snapshot of plant species.
Since 2020, more than 18,800 new species of plants and fungi have been named.
All were added to the World Checklist of Vascular Plants, an international database of scientifically described plant species.
It currently includes over 350,000 species.
Dr Matilda Brown, conservation science analyst at Royal Botanic Gardens, Kew, explains how Kew was able to give such estimations.
“How do we pull this number for things that we don’t even know are out there? And the way we do that is we looked at things that have been described and we looked at when they were described,” she says.
“So we collected the information from the world checklist and we looked at the year that something was described versus the probability of it being threatened. And we found this really clean relationship, this statistically really well-supported relationship that basically says things described in the 1800s, probably not threatened. But if we look at things described in 2019, 2020, things are much more likely to be threatened.”
One way Kew is helping to preserve as many species as possible is by storing seeds and looking after some of the last specimens of plants and fungi in its nursery.
“The main threats to plants are habitat loss, land use change. We know that that’s coming up as the immediate, that’s the short-term threat that most threatened species are facing. That’s not to say we’re not worried about climate change. It’s definitely on the horizon. And there’s increasing evidence to suggest that climate change is going to contribute to those threats. But reducing that habitat loss, keeping systems intact and keeping that vegetation intact is really what’s going to do the best for our threatened species,” Brown says.