An interesting plant. There are chemicals in wild parsnip called furocoumarins which cause what dermatologists call "phyto-photo-dermatitis." People who are unfortunate enough to come into contact with the plant sap and then expose their skin to sunlight, get nasty painful burns and blisters. But if the sap gets on your skin at night, there's no reaction. It's not an allergic reaction, but a chemical burn.
