Urtica dioica, often called common nettle or stinging nettle, is a herbaceous perennial flowering plant, native to Europe, Asia, northern Africa, and North America, and is the best-known member of the nettle genus Urtica. The species is divided into six subspecies, five of which have many hollow stinging hairs called trichomes on the leaves and stems, which act like hypodermic needles, injecting histamine and other chemicals that produce a stinging sensation when contacted by humans and other animals. Urtica dioica has a flavour similar to spinach and cucumber when cooked and is rich in vitamins A, C, iron, potassium, manganese, and calcium.