How many tree species are on Earth?

On Jan. 31, 2022, researchers unveiled the world’s most extensive forest database, comprising more than 44 million individual trees at more than 100,000 sites in 90 countries – helping them calculate that Earth has roughly 73,300 tree species. South America, home to the Amazon rainforest and Andean forests, is populated with 43% of the planet’s tree species. The study was published in the journal Proceedings of the National Academy of Sciences.