John Craven visits Westonbirt, The National Arboretum, in Gloucestershire, to see it in all its autumnal glory. At this time of year, 2,500 different species of trees, from around the world, burst into a mosaic of colour. John finds out about the history of the arboretum's autumn colour parties, which were celebrated in the Victorian period, and discovers why leaves change colour at this time of year. He meets the team saving the arboretum's older trees from the winter storms and plants a rare native Sorbus tree to help preserve the species for the future. In celebration of the season, we also delve into the Countryfile archives to revisit autumn stories from around the UK.