Ending violence and conserving forests are interconnected goals.
Kelsey Riley and Wes Dixon graduated from Eastern York High School, in Pennsylvania, back in 2008, and the huge tree now dwarfs them.
Earth's tropical forests are "time capsules" of human history stretching back hundreds of years.
The latest results could have significant implications for our understanding of how the planet will adapt to climate change.
Pando is a unique "forest of one tree" covering some 106 acres of the Fishlake National Forest in Utah.
A new Republican piece of legislation will threaten about 58.5 million acres, or 91,000 square miles, of protected forest land according to environmental rights activists.
The effects of climate change on forests depend on the type of tree.
The stunning colors of autumn may also disappear.
The report also suggests building huge ventilation tunnels to create wind which will lift the smog from the city
Scientists expect global warming to impede forests' ability to absorb the Earth's carbon.