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In "Dear Future Generations: Sorry", Prince Ea, American rapper and activist, expresses an emotional message to the upcoming generation in a 6 minutes video. In his video, he apologizes to the future generations for numerous problems we have today like climate change, animal extinction and deforestation; where he makes the following claim:

Well let me tell you that trees are amazing, and I mean, we literally breath the air they are creating, and they clean up our pollution, our carbon, store and purify water, give us medicine that cures ours diseases, food that feeds us. Which is why I am so sorry, to tell you that, we burned them down. Cut them down with brutal machines, horrific, at a rate of 40 football fields every minute, that's 50% of all the trees in the world all gone in the last 100 years.

The video has gone viral and been viewed more than 80,000,000 times, Facebook indicated. Dubious of Ea's claim, I did some small research to find a statement by the Food and Agriculture Organization (FAO) saying that in the last years, the volume of forest growth was up by 42%, which partially contradicts with Prince Ea's claim:

Forest growth nationally has exceeded harvest since the 1940s. By 1997 forest growth exceeded harvest by 42 percent and the volume of forest growth was 380 percent greater than it had been in 1920.

Mother Nature Network analyzed the report and concluded that there were more trees than there were 100 years ago.

Did 50% of the world's trees perish in the last 100 years?

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    Well, look, 100% of the world's people perished in the last 200 years, right? So 50% of trees perished in the last 100 years just means that of all trees alive 100 years ago, 50% are no longer alive. But of course it could still be that there are many trees less than 100 years old. Maybe Prince Era and FAO are both right! – GEdgar Aug 30 '15 at 18:14
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    Can you clarify whether the claim is that there are 50% fewer trees in the world than 100 years ago, or that 50% of the trees alive 100 years ago are now dead? – DJClayworth Aug 31 '15 at 2:50
  • I think the quotes provided and the context of the speech in which they were delivered, make it clear that he was suggesting there were 50% fewer trees (or equivalently 50% of the biomass, or 50% of the land area) rather than that the half-life of trees is less than 100 years. – Oddthinking Aug 31 '15 at 10:10
  • Prince Ea's lyrics are not clear. Since it is addressed to a future generation, it could be addressed to a time 100 years from now. He could be saying that between now and 100 years in the future we will have killed 50% of the trees in the world. The real claim here is "at a rate of 40 football fields every minute". Is that really today's rate of deforestation? – called2voyage Jun 22 '16 at 15:57
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The UN Food and Agricultural Organisation (FAO)'s forest report State of the World’s Forests states that forests cover 4 billion hectares of the Earth's surface:

Forests currently cover about 4 billion hectares, about 31 percent of the earth’s land surface (FAO, 2010b).

It also provides a graph of human deforestation over the past 200 years:

enter image description here

As can be seen in the graph, roughly 0.6 billion hectares of forest has been lost over the past century, from 1900 (1.2 billion hectares lost) to 2010 (1.8 billion hectares lost).

Therefore, the total forest cover has decreased by approximately 13% in the past century, which hardly reaches the level claimed. Unless the forests cut down are almost 4 times denser per unit area than the average forest, it is also unlikely that half of the total number of trees was cut down.

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    does this take into account re-planting of trees? – Himarm Sep 1 '15 at 14:14
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    @Himarm The text near the graph is not very clear, but later on the paper seems to imply that the graph is for net deforestation. In any case, the total amount of forest has definitely not decreased by 50%. – March Ho Sep 1 '15 at 14:26
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    @Bakuriu Only very, very partly. – gerrit Sep 7 '15 at 15:02
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    @MarchHo Where you say "from 1900 (0.9 billion hectares lost) to 2010 (1.95 billion hectares lost)", I think you are reading the population line instead of the deforestation line. Instead, it's about 1.2 billion hectares lost by 1900 and 1.8 hectares lost by 2010. 0.6 hectares lost in the past century. 0.6/(4 + 0.6) = 0.13. 13% lost in the past century. – DavePhD Jan 19 '16 at 15:25
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    @gerrit I don't know whether the satellite evidence can separately account for trees, but it clearly shows the earth is getting significantly greener in the last few decades and much of this is driven by carbon dioxide levels. – matt_black Jun 25 '16 at 10:12

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