"Veratrum" is found throughout temperate regions of the Northern Hemisphere. The genus has possibly as many as 40 species, depending on how finely some of the widely distributed species are divided and whether the closely related genus "Melanthium" is included or not. Plants grow from a combination of short rhizomes and bulbs. They generally have quite large leaves and inflorescences in which individual flowers vary in colour from white to green, yellow or purple. They contain a variety of alkaloids which make them poisonous, although some have medical uses. Some species are cultivated for their form as well as their flowers.