Groundbreaking new research has revealed that there are around three trillion trees on Earth, but if current trends continue there might not be any left in a little over 300 years.
According to the new research, we are removing 15 billion trees a year - but only replanting five billion of them. Under those estimates, if deforestation continues at the same rate, then all trees could have disappeared from Earth in 304 years.
The three trillion estimate is eight times as big as previously thought, although researchers have warned the higher number does not change anything.
The assessment, carried out by a team at Yale University who combined ground survey data with satellite images, revealed an annual net loss of "about a third of a percent of the number of trees globally," according to the report's co-author Dr Henry Glick.
"That doesn't seem to be an insignificant portion and should probably give us cause for considering the role that deforestation is playing in changing ecosystems," he said.
Dr Crowther, who led the research, said the new total represents at least 420 trees for every person on Earth, but told the BBC's Science In Action programme: "It's not like we've discovered a load of new trees; it's not like we've discovered a load of new carbon.
"So, it's not good news for the world or bad news that we've produced this new number.
"We're simply describing the state of the global forest system in numbers that people can understand and that scientists can use, and that environmental practitioners or policymakers can understand and use."
Crowther pointed out a comparison with ancient forest cover suggests we could have already removed three trillion trees since the last ice age - 11,000 years ago.
"Europe used to be almost covered by one giant forest and now it's almost entirely fields and grasslands. Humans are absolutely controlling tree densities," he told BBC News.