The last Friday in April is national Arbor Day. It's a great time to plant trees. And it's an especially great time to plant ...

In 1997, Julia Hill started a tree sit in a California redwood to protest logging efforts. For 738 days, Hill lived on two platforms in cramped, windy, and wet conditions. She ultimately reached an ...

In a new study, researchers used more than 5 million measurements from individual trees across much of eastern North America and showed the rate at which introduced species are spreading has increased ...