Cicuta virosa, the cowbane or northern water hemlock, is a species of Cicuta, native to northern and central Europe, northern Asia and northwestern North America. It is a perennial herbaceous plant which grows up to 1–2 m tall. The stems are smooth, branching, swollen at the base, purple-striped, and hollow except for partitions at the junction of the leaves and stem. In cross section the stems have one flat side and the other sides are rounded.... (Wikipedia)