Mystery #1Tier 1trees / growth

How can the rings inside a cut tree tell you exactly how old it was?

Saw straight through a tree trunk and you find rings inside, circle upon circle spreading out from the middle. People say you can read them to find out exactly how old the tree was when it fell. But how can a pattern of plain circles keep such a careful record of the years?

A polished slice cut across a tree trunk, its bark still on the edge and pale and dark growth rings circling out from the centre — Photo: Biswarup Ganguly · CC BY 3.0 · via Wikimedia Commons

Your guess

What's your hunch? How could the rings tell you the tree's age so exactly?

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