Matt Baker and Charlotte Smith are in Kielder in Northumberland to explore some of the 250 square miles of England's largest forest. Charlotte discovers how this man-made landscape supplies a quarter of England's timber - from the joists in your house to the chair you sit on - and heads to a ‘rock festival' as Northumberland Wildlife Trust celebrates its 50th anniversary by revealing secrets going back millions of years that are hidden in the stones that shape this landscape. Matt finds out how the forest is managed for its wildlife, helping a team clean out osprey nests 65 feet high up and foraging for fungi that help the forest thrive. Adam Henson gets to grips with the latest entrants into the milk market - camels - and Joe Crowley investigates whether schemes to reduce the impact of big building projects on wildlife are working.