Tree rings are kind of like a tree’s personal diary – they record everything that happens to them - from the weather, to fires and insects. One of our listeners wanted to know how tree rings form, and if you can actually tell the age of a tree by counting the rings. We asked forest ecologist Diana Macias to help us with the answer. 

Do you have a stumper of a question for Moment of Um? Send it to us at, and we’ll get to the root of the problem.