The Manchineel tree is a poisonous tree, just standing underneath it in a rain storm can give you blisters.
The tree and its parts contain strong toxins, some unidentified. Its milky white sap contains phorbol and other skin irritants, producing strong allergic dermatitis.[2] Standing beneath the tree during rain will cause blistering of the skin from mere contact with this liquid (even a small drop of rain with the milky substance in it will cause the skin to blister). Burning the tree may cause blindness if the smoke reaches the eyes. @Curionic
#staycurious
Even more curious? Check out this great article by Montem Outdoor Gear - Common Hiking Injuries & How To Treat Them - Great article on how to cure those nasty blisters and other common hiking injuries.