How many trees are on Earth?

Researchers led by Thomas Crowther at Yale combined satellite images with more than 400,000 ground measurements of tree density to reach an estimate of around 3.04 trillion trees. That was about eight times higher than previous estimates. The study also found that the number of trees has fallen by roughly 46 percent since the start of human civilisation. Around 15 billion trees are estimated to be cut down each year. Tropical and subtropical forests hold the largest share, while the boreal forests of Russia, Scandinavia and North America have the highest tree densities.