Urticaceae

flowers in clusters from the leaf axils

 

URTICACEAE

Juss.

pronounced: ur-tick-AY-see-eye

the nettle family

Urtica is the Latin name for the stinging-nettle. The family consists of herbs, shrubs, small trees and a few vines. Many of them have stinging hairs on the leaves and stems. These hairs contain a skin-active poison that can cause severe stinging lasting for days. The flowers concentrate in clusters from the leaf axils. They have no petals: male flowers have a 4-lobed calyx and nearly always 4 stamens; female flowers are 2- or 4-lobed and have a pistil that produces a single seed. The curled stamens of the male flowers straighten quickly as the flowers open, releasing the pollen. The dry, one-seeded fruit is often enclosed by the outer whorl of the flower cluster. Probably the most virulent of the stinging plants in this family is Dendrocnide moroides, of the tropical Australian rainforests. The initial pain caused by contact with this plant is excruciating, and will persist for several days before easing. Afterwards it can recur for several months whenever the affected area of skin is exposed to either hot or cold air, or water, or rubbing.

 


Photograph © Donald Simpson 2011