A rather violent tree, planted in the Hogwarts grounds
They planted the Whomping Willow the same year that I arrived at Hogwarts. People used to play a game, trying to get near enough to touch the trunk.
‘MIND THAT TREE!’ Harry bellowed, lunging for the steering wheel, but too late –
With an ear-splitting bang of metal on wood...
Harry Potter and the Chamber of Secrets
By J.K. Rowling