T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Urtica urens (Dwarf Stinging Nettle)

Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Urticales
Family: Urticaceae
Genus: Urtica
Species: Urtica urens
Common names: Stinging nettle, Annual Nettle, Dwarf Nettle, Small Nettle

Urtica urens is an erect herbaceous annual plant and is a native to Eurasia and is common throughout New Zealand, found in gardens, under trees, sheep camps and where pasture has been disturbed for cropping or pasture renewal.
It grows up to 60cm tall. It has short stinging bristles on the leaves and stems with clusters of tiny green flowers in the leaf axils. The leaves are dark green and heart-shaped up to 8cm long and arranged in opposite pairs with stinging bristles. The fine bristles release poison when the skin brushes against the leaves or the stem.
U. urens is also a food plant for the New Zealand Red Admiral butterfly (Bassaris gonerilla, syn Vanessa gonerilla, syn Papilio gonerilla), and more particularly the Australian/New Zealand Yellow Admiral butterfly (Bassaris itea) Urtica urens is a herb traditionally used to support the skin and soothe common itchiness. It is not readily grazed by stock.

There is another stinging nettle that is a native to New Zealand, Urtica ferox the tree nettle. See details a http://www.terrain.net.nz/friends-of-te-henui-group/plants-native-botanical-names-r-to-z/tree-nettle-urtica-ferox.html  

Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/