Sium latifolium, also known as water-parsnip, is a species of flowering plant that belongs to the carrot family, Apiaceae. It is an aquatic plant that can be found in shallow waters such as ponds, marshes, and streams across Europe, Asia, and North America. Sium latifolium is characterized by its large, compound leaves and clusters of small white flowers that bloom in the summer.
Some of the synonyms for Sium latifolium include broad-leaved water-parsnip, cowbane, and spotted cowbane. In some regions, it is also known as water hemlock, which can be confusing as this is also the common name for a highly poisonous plant that belongs to the same family. Sium latifolium has historically been used for medicinal purposes, although caution must be exercised as it can cause dermatitis and gastrointestinal complications.