Every year trees add layers of wood as they grow. These growth rings preserve a record of the unique chemical and environmental conditions the tree experienced as the growth occurred. Dendrochronology combines the techniques of botany and climatology to reconstruct ancient climates and environments.
Methuselah is a bristle cone pine tree living in the White Mountains of California. It is the oldest known living tree in existence. This video tells the story of Methuselah's life, based upon the evidence preserved in its rings. It's a compelling, true story with implications for the impacts of modern lifestyles and land use patterns.
View on YouTube: https://goo.gl/KNloYD
Methuselah NOVA site: http://www.pbs.org/wgbh/nova/methuselah/