Did you know you can tell how old a tree is by counting the number of rings on its trunk? Each ring represents one year’s growth. Scientists call the study of tree rings dendrochronology.

What you need:

• Part of an old tree stump – it must have a flat surface
• A damp cloth
• A ruler
• A marker pen

How to do the experiment:

1. Take the piece of wood and wipe the surface with a damp cloth to clean off any dust or dirt.
2. Using the ruler and marker, draw a line from the centre of the stump to the edge.
3. Using the marker, mark off the rings that intersect your line.
4. Count the number of intersections and this is how old the tree is in years.

Want to know more?

Tree rings can help you find out how wet a particular season was. How? When a tree gets a lot of water, it grows more. Its rings are thicker as a result. Karri trees in WA’s South West are some of the largest in the world. Some are almost 75 metres tall and over 400 years old.