5. Ash dieback fungus

Available for over a year

When trees infected with the ash-dieback fungus were first recorded in the UK in 2012, there was widespread alarm. By 2016, are we closer to knowing what the final toll will be on our ash trees? With an uncertain political future, how do we limit the risks posed by other invisible invaders? Derek Mooney intends to find out. Telling the stories of non-native invasive species and our complicated attitudes to them and with an uncertain political future, how do we police our ecological borders? Producer: Ellie Sans First broadcast on BBC Radio 4 in August 2016.