Dame Judi has a love of trees: she has even created her own garden full of trees, with a new one added every time someone close to her passes away.
In this documentary she looks at both the history and science of trees. She tries to understand how trees exactly work, using among other things a microphone to hear what trees sound like in the inside, and a 3D scanner to create a digital copy of her favourite oak, complete with over 260,000 leaves.
Judi Dench: My Passion for Trees is on BBC One at 20.00.
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