Derek Mooney looks at the despised plant Japanese knotweed, but does it deserve its enemy number one status? From 2016.

Japanese knotweed evolved to grow on the slopes of Japanese volcanoes. It's harsh home makes it a thug of a plant outside it's natural range with a seemingly magical ability grow in the most unlikely places.

In the more than 100 years since a few female specimens were brought to UK shores as an ornamental garden plant it has spread across the country and is now probably the most hated plant in the UK. But is it really the Great Invader we believe it to be? 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.