Mount Head (2002)

A miserly man eats the pits of some cherries he can't stand throwing out. A tree starts growing from the top of his head. He cuts it off; it grows back. After a while, he gives up and lets it grow, but the crowds that gather on top of his head to enjoy the tree (and leave huge mounds of trash) eventually drive him to uproot the tree. This leaves a crater on top of his head, which fills with water, which becomes a popular lake.