More than 3 trillion trees now grow on Earth, seven times more than scientists previously thought. But it's also trillions fewer than there used to be, a new study concludes. A United ...

Add Yahoo as a preferred source to see more of our stories on Google. A year after a wildfire, the U.S. Forest Service assesses the damage to figure out how many trees need to be planted to restore ...

A year after a wildfire, the U.S. Forest Service assesses the damage to figure out how many trees need to be planted to restore the forest. But research shows that much more time is needed to ...