NOVA Online | Tracking El Niño | What else can tree rings tell you?

What else can tree rings tell you?

Cross-section from a sugar pine in the Sequoia National Park shows a series of fire scars.

Besides telling you about climate, tree rings also hold information about other events that happened in the past, such as insect outbreaks, glacial activity, volcanic events, fires, floods, and earthquakes that might have occurred in the area.