Australian Tropical Rainforest Plants - Online edition

Urtica incisa Poir.

Herb (herbaceous or woody, under 1 m tall)
Shrub (woody or herbaceous, 1-6 m tall)
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Habit, leaves and flowers. © CSIRO
Scale bar 10mm. © CSIRO
10th leaf stage. © CSIRO
Cotyledon stage, epigeal germination. © CSIRO

Poiret, J.L.M. (1816) Encyclopedie Methodique. Botanique Suppl. 4 : 224. Type: Cette plante croit a la Nouvelle-Hollande, ou elle a ete decouverte par M. de Labillardiere. (V.s. in herb. Desf.).

Common name

Stinging Nettle; Scrub Nettle


Usually flowers and fruits as a shrub about 1 m tall but also flowers when smaller.


Twigs, petioles and both the upper and lower surfaces of the leaf blade clothed in stinging hairs which inflict short-term pain. Leaf blade about 5-12 x 3-6 cm, margin coarsely toothed or finely lobed. Stipules about 5-15 mm long. Petiole grooved on the upper surface.


Inflorescences usually longer than the petioles. Tepals dimorphic, two large and two small, larger tepals about 1.5 mm long, +/- glabrous. Anther filaments corrugated on the inner curve when at the flower bud stage but straightening when the filament flicks outwards and throws pollen to the wind. Pollen +/- white.


Infructescence up to about 5-6 cm long, stinging hairs usually present on some parts. Nuts or achenes resemble seeds and are ovoid and about 2 mm long. Embryo small, less than 1 mm long.


Cotyledons +/- orbicular, about 2 mm diam. First pair of true leaves opposite, margin toothed, upper surface clothed in white hairs and stinging hairs. At the tenth leaf stage: all parts clothed in stinging hairs, leaves broadly lanceolate, margin coarsely toothed. Stipules about 3 mm long. Seed germination time 19 days.

Distribution and Ecology

Endemic to Australia, occurs in NEQ and in south eastern Queensland southwards as far as Tasmania. Altitudinal range in NEQ from 500-800 m. Grows in disturbed areas in well developed upland rain forest, usually most abundant in rain forests on very fertile red soils derived from recent basalt flows.

Natural History & Notes

This plant inflicts a painful sting but it does not last long.

Food plant for the larval stages of the Australian Admiral Butterfly. Common & Waterhouse (1981).

Urtication, flogging with nettles, is a traditional European method of treating rheumatism. The same therapy was found in Aboriginal medicine. Cribb (1981).

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