Dendrochronology—the art of tree-ring counting—allows us to precisely date trees. Based on the rings in its trunk, a bristlecone pine in eastern California known as Methuselah is said to be the ...

Every year a new ring is added to a tree's trunk and branches, just beneath the bark. The thickness of this ring depends on how much the tree grows during the year—favorable growing conditions ...

But few people know that the rings in trees can tell us much more than just a tree’s age. And perhaps even fewer know that there is a field of science dedicated to the study of tree rings.