There are 14 per cent more tree species than previously thought, according to what researchers are calling the first ‘scientifically credible’ estimate.

Of the 73,300 estimated species, the researchers predict there are 9,200 that are yet to be discovered. But most rare species are in tropical forests that are fast disappearing because of climate change and deforestation.

The study is based on a database of tens of millions of trees in more than 100,000 forest plots around the world, the researchers used statistical techniques to predict the likely number of tree species, correcting for gaps in existing data.

The findings suggest more must be done to protect the incredible life forms needed for food, timber, and medicine and to fight climate change by sucking carbon dioxide from the air.

Lead researcher Dr. Peter Reich of the University of Minnesota in St Paul said that the findings highlighted the vulnerability of global forest biodiversity, our data will help us assess where biodiversity is the most threatened.

He added: “This is in the tropics and subtropics of South America, Africa, Asia, and Oceania and those are places where we discovered hotspots of known and unknown rare species”.

More than 140 international researchers worked on the study, in the Proceedings of the National Academy of Sciences journal.

Dr. Yadvinder Malhi, of the University of Oxford, was quoted by BBC News as saying that tropical forests were the “global treasure chests of biodiversity” and significant absorbers of carbon dioxide emissions, slowing global warming.

“This study shows that tropical forests are even more diverse in their trees than we had previously imagined,” he added.