Sium latifolium is a species of flowering plant in the family Apiaceae known by the common names great water-parsnip, greater water-parsnip, and wideleaf waterparsnip. It is native to much of Europe, Kazakhstan, and Siberia.This plant grows in wet habitat such as swamps and lakeshores, sometimes in the water. It is a perennial herb with a hollow, grooved stem up to 2 meters tall. The herbage is green and hairless. The leaves are up to 30 centimeters long with blades borne on hollow petioles that ...