Urticaceae

Urticaceae /ɜːrtᵻˈkeɪsiː/, the nettle family, is a family of flowering plants. The family name comes from the genus Urtica. Urticaceae includes a number of well-known and useful plants, including the nettles, ramie (Boehmeria nivea), māmaki (Pipturus albidus), and ajlai (Debregeasia saeneb).

The family includes about 2600 species, grouped into 54 to 79 genera according to the database of the Royal Botanic Gardens, Kew. The largest genera are Pilea (500 to 715 species), Elatostema (300 species), Urtica (80 species), and Cecropia (75 species).

Urticaceae can be found worldwide, apart from the polar regions.

Description

Urticaceae can be shrubs (e.g. Pilea), lianas, herbs (e.g. Urtica, Parietaria), or, rarely, trees (Dendrocnide, Cecropia). Their leaves are usually entire and bear stipules. Urticating (stinging) hairs are often present. Urticaceae have usually unisexual flowers and can be both monoecious or dioecious. They are wind-pollinated. Most disperse their pollen when the stamens are mature and their filaments straighten explosively, a peculiar and conspicuously specialised mechanism.