How to track the life of a tree

Scientists in California have set up an ambitious experiment to track the life histories of some of the world's oldest and tallest trees.

Researchers are concerned that climate change might be causing some of the giant trees of Yosemite National Park to die prematurely.

But tracking trees that live for centuries involves some seriously long-term research.

Peter Bowes joined a group of scientists from the University of Washington for a unique summer camp in the forest.