The story for kids
Tree rings. Every year, a tree's trunk adds one new ring. Count the rings, and you'll know how old the tree is! A wide ring means a good, rainy year, and a thin one means a dry year.
Facts
- Every year a tree's trunk adds one new ring.
- Count the rings, and you'll know how old the tree is.
- A wide ring means a good, rainy year, and a narrow one means a dry year.
Numbers
- One ring
- One year
For grown-ups
Annual rings form because in spring the cambium produces wide, pale wood, while at the end of summer it produces narrow, dense wood. From the width of the rings, scientists can reconstruct past climates. This is called dendrochronology.