Faux de Verzy, France

The forest in Verzy has a small area at the top of the hill where the trees are sometimes afflicted by dwarfism. The trees develop fantastically twisted trunks and umbrella like canopies. Most of the dwarf trees are Beeches of which this area holds the world's principle natural reserve. 

The reason for the dwarfism is not known. Theories point to a genetic mutation, but this doesn't explain the occasional oak or chestnut showing the same features. Possible causes could be an environmental cause or a as a result of a pathogen, but nothing has been found despite extensive studies.