In the 19th. century, encouraged by the booming opium trade,  UK horticulturalists tried to establish an opium poppy crop. Unfortunately, it was eaten by what was described as a plague of hares.
The hares later lined up to eat the first and only British cocaine plant crop, giving rise to the saying 'mad as a march hare.' (I may be making up this last bit.)
Have a relaxed weekend, everyone. 

Many thanks to BikerBear for hosting.