Bristlecone pines are considered to be one of the world’s longest-lived organisms, some reaching ages of 5,000 years. One researcher is hoping that by studying the trees he can unlock some of the climate change mysteries of the past.
Counting the rings makes it possible for researchers to determine a tree’s age. Examining width and variations in the rings over time gives scientists an idea of what kind of stress the trees might have been under.
Ring width, for an example, is an indicator of a tree’s health. When it’s a good growing season, more of a tree’s energy goes into producing wood for the ring. A poor growing season – temperatures too cold, precipitation too low – means a much narrower ring.
“The question that’s asked is a thousand years ago, trees were growing at higher elevations than they are now,” he said. “We know that the tree line is limited by temperature. What does that mean about what the temperatures were like a thousand years ago?”