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 ...

Look up at the night sky and you might feel dwarfed by the glimmer of countless stars. Now shift that view downward, press your mind to the ground and the green world under your feet—and you’ll find ...

Here's a look at Christmas trees by the numbers: 3 Rank of Pennsylvania in the nation for the number of Christmas tree farms 4 Rank of Pennsylvania in the nation for acreage of Christmas trees in ...