The Royal Botanic Gardens, Kew and Stockholm University researchers say it's the first time scientists have compiled a global overview of which plants have already become extinct.
"Plants underpin all life on Earth, they provide the oxygen we breathe and the food we eat, as well as making up the backbone of the world's ecosystems - so plant extinction is bad news for all species", said Dr. Eimear Nic Lughadha, the study's co-author and a Kew conservation scientist. The study shows that the number of extinct plant species is four times higher than previous compilations and twice the combined 271 birds, mammals and amphibians record extinct in the last two-and-a-half centuries.
A bright spot: Researchers also found that 430 species once considered extinct were subsequently rediscovered.
Most people can name a mammal or bird that has become extinct in recent centuries, but few could name an extinct plant, said Dr Aelys Humphreys of Stockholm University.
Experts found that 500 species are no longer found on Earth.
For comparison, the researchers said animal extinction is occurring at least 1,000 times faster than the normal rate of extinction, however the report notes that researchers believe the plant extinction rate has been underestimated.
Hawaii stands out as having the most recorded extinctions, followed by the Cape provinces of South Africa and Mauritius, with Australia, Brazil, India and Madagascar also being among the top regions.
The biggest losses are on islands and in the tropics, which are home to highly valued timber trees and tend to be particularly rich in plant diversity. "This new understanding of plant extinction will help us predict (and try to predict) future extinctions of plants, as well as other organisms".
"'Millions of other species depend on plants for their survival, humans included, so knowing which plants we are losing and from where will feed back into conservation programmes targeting other organisms as well".
"We depend on plants directly for food, shade and construction materials, and indirectly for "ecosystem services" such as carbon fixation, oxygen creation, and even improvement in human mental health through enjoying green spaces", he commented.