Water Hemlock Most violent toxic plant in North America. Grows in meadows and along stream banks, it is the plant's roots that contain deadly sap that when touched or eaten, causes grand maul siezures and death.
Wild Parsnip (roots editable) BUT the plant produces a compound in its leaves, stems, flowers and fruits that causes intense, localized burning, rash, severe blistering from the sap and discoloration on contact with the skin on sunny days. This reaction is not brought on by contact with the foliage of the plant, only by contact with the sap. BE CAREFUL!!