Dutch Elm
Duth Elm is a super deadly fungus spread by the elm bark beetle. It can kill an entire elm in three weeks by clogging its water-conducting vessels! Yikes! It began to spread in the UK in 1968. It is responsibly for killing more than a third of southern England’s 23 million elms.
Grey Squirrel
The American Grey Squirrel has totally devastated Britain’s native population of red squirrels! It first appeared in England’s countryside sometime around 1876.