Whether you’re walking along a city sidewalk or hiking deep in the forest, you might occasionally notice paint marks on tree trunks. Those marks are codes used by forestry workers and contractors to ...

A tree-climbing scientist and his team have learned surprising new facts about giant sequoias by measuring them inch by inch.

Perhaps you’ve wandered through a forest or strolled into a neighborhood park and found tree trunks — and wondered if counting the rings on a trunk is truly a way to know the tree’s age. “Most of us ...