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

Urtica incisa (Scrub nettle)

Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Rosales
Family: Urticaceae
Genus: Urtica
Species: U. incisa
Binomial name: Urtica incisa
Synonym: Urtica dioica subsp, gracilis
Common names: Scrub nettle, Dwarf bush nettle, Stinging nettle

Urtica incisa exotic, many branched, upright perennial, herb native to streams and rainforest of eastern and southern Australia. It is common throughout most of NZ, but it is uncommon in the Northland, Taranaki, the South Island’s West Coast and Fiordland. It inhabits damp gullies in lowland to montane forests margins and shaded open places on roadsides, pasture and general wasteland. It often found growing along lake shores and under willow abutting pasture. 

Urtica incisa leaves are triangular and opposite, 5-10 cm long, with serrated margins and have stinging hairs which cause irritation to the skin. It has cream coloured, 4 petalled flowers which are very small (less than 3mm across), in loose spikes on stalks arising from the bases of the leaves. There can be mixed spikes on the same plant with the male flowers below the female flowers, or the plants can be dioecious with male and female flowers on different plants.
Red Admiral caterpillars eat Urtica incisa leaves.

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