The costly problem of ash dieback has been highlighted in New Scientist.
This fungal disease caused by Hymenoscyphus fraxineus was first detected in Britain in 2012 having crept across Europe from the east. Its origin is Asia and it affects the common ash Fraxinus excelsior. It's predicted to destroy more than 90% of the many million ash trees, killing saplings within a year of infection. Coming on top of Dutch elm disease and various infections of both English oak species, it's a concern in a country that has, through millennia, lost most of its native forests.