Chris Packham: Plant a Tree to Save the World

Chris Packham, along with guest presenters including Mastermind host John Humphrys, aims to raise enough money to plant 100,000 trees across Britain, by asking viewers to contribute to The Woodland Trust. Martin Hughes-Games, JB Gill and Clare Nasir also take a closer look at the science of trees, exploring how they can lower carbon emissions, fight flooding and reduce pollution.