Urtica perconfusa


Urtica: from the Latin verb urere which means "to burn"

Common Name(s)

swamp nettle

Current Conservation Status

2012 - At Risk - Declining

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2009 - At Risk - Declining
2004 - Gradual Decline


2012 - Sp
2009 - Sp


Urtica perconfusa Grosse-Veldmann et Weigend



Brief Description

Scrambling to sprawling, much-branched herb forming patches up to 2 m long. All parts covered in stinging hairs (these conspicuous but sparse on leaves). Leaves narrow, 40–100 × 4–10 mm, margins sharply toothed. Flowers green to reddish, clustered in short spikes in leaf axils.

Flora Category

Vascular - Native

NVS Species Code


The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.

Structural Class

Dicotyledonous Herbs other than Composites


Urtica incisa var. linearifolia Hook.f.; Urtica linearifolia (Hook.f.) Cockayne


Endemic. New Zealand - and North and South Island s from the Central North Island south.


Fertile, lowland swamps, lakes and river margins, swampy shrubland and forest, often growing over tree stumps and rushes or through dense sedges such as swards of Carex secta.


Lianoid, slender, perennial, rhizomatous herb 0.45–2.0 m, usually much-branched, scrambling or climbing. Stem indumentum of few stinging hairs with pluricellular base c. 0.2–0.5 mm overall and erect setae 0.2–0.4 mm long and few simple trichomes 0.2–0.3 mm long. Leaf lamina 40–100 × 4–10 mm narrowly ovate; surface sparsely pubescent with short simple trichomes 0.2–0.5 mm long and few stinging hairs (abaxially only on the veins), adaxially with punctiform cystoliths; leaf base rounded; margins regularly dentate, rarely doubly dentate, with 12–20 teeth on each side; leaf apex acuminate; lamina thinly membranaceous; stipules free (4 per node) 2–4 mm long; petioles thin, flexuose, 15–45 mm long. Plants monoecious. Staminate flowers with tepals c. 1.3–1.8 mm long. Pistillate flowers with short tepals 0.5–0.8 mm long and long tepals 0.8–1.2 mm long, sparsely pubescent, esetulose. Inflorescence glomerulous, 3–10 mm long, usually shorter than petioles. Mature fruit with longer tepals 1.2–1.5 mm long, achenes subcircular in outline, rounded at base and at the tip, laterally flattened, c. 1.2–2.0 × 0.8–1.3 mm.

Similar Taxa

Easily distinguished from all other New Zealand nettles (Urtica) by the vine-like (lianoid) stems, sprawling growth habit, narrowly ovate leaves with rounded bases and by the inflorescences which are glomerulose, and 3–10 mm long


Flowering occurs throughout the year

Flower Colours

Green,Red / Pink


Fruits may be found throughout the year

Propagation Technique

Very easy from rooted pieces, stem cuttings and fresh seed. Often spontaneously self-sows in cultivation.


A sparsely distributed species of lowland to montane lake margins and fertile to semi-fertile wetlands. Easily overlooked because of its penchant for grow at the base of Carex secta trunks, or threaded through Phormium tenax. Being an adaptable species it is often found within willow (Salix spp.) car, sometimes as a low epiphyte on willow trunks. In all these habitats it is at risk from wetland clearance, drainage and also the spread of weeds such as wandering jew (Tradescantia fluminensis). Some large populations in the Horowhenua have been destroyed by the canalisation of streams and through willow control.

Chromosome No.

2n = 24

Endemic Taxon


Endemic Genus


Endemic Family


Where To Buy

Not commercially available. Some plants are held by specialist native plant growers and botanic gardens. An attractive plant but with a vicious sting! Will hybridise readily with U. aspera and U. sykesii. Such hybrids have been collected from the wild and in cultivation.



Fact Sheet by Peter J. de Lange (15 February 2016). Description based on Grosse-Veldmann et al. (2016).

References and further reading

Grosse-Veldmann, B.; Conn, B.J.; Weigend, M. 2016: Weeding the nettles IV: A redefinition of Urtica incisa and allies in New Zealand and Australia, including the segregation of two new species Urtica sykesii and U. perconfusa. Phytotaxa 245(4): 251-261.

This page last updated on 30 Jul 2017