Stinging nettle-Urtica dioica L.-Poisonous plant

Stinging nettle

Other names:

Nettle, big string nettle, common nettle, stinging nettle, gerrais, isirgan, kazink, nabat al nar, ortiga, grande ortie, ortie, urtiga, chichicaste, brennessel, gross d’ortie, racine d’ortie

General poisoning notes:

Stinging nettle (Urtica dioica) is found across Canada and includes a wide-ranging native subspecies and an introduced subspecies found in the Maritime Provinces. The plant can form large colonies in orchards, farmyards, old pastures, ditches, and waste places. The stinging hairs readily break, allowing the secretions to enter skin. Humans receive a painful sting, followed by a small reddish swelling and prolonged itching and numbness. Initial reactions last only a few minutes but repeated contact can cause the pain to intensify and last for days. Hunting dogs in the United States were poisoned and died after massive exposure to the plants (Bassett et al. 1977, Mitchell and Rook 1979, Anon. 1982).

Description:

Herbs perennial, dioecious, rarely monoecious. Rhizomes woody, stoloniferous. Stems simple or few branched, 40-100 cm tall; stems and petioles often densely or sometimes sparsely covered with stinging and setulose hairs. Stipules free, linear, (2-)5-8 mm; petiole 2.5-4 cm; leaf blade ovate, sometimes lanceolate, 5-13 × 2.5-6 cm, often herbaceous, (3-)5-veined, lateral basal veins reaching distal margin and anastomosing, secondary veins 3-5 each side, adaxial surface sparsely covered with stinging and setulose hairs, abaxial surface often densely covered with long, stinging and setulose hairs along veins, base cordate, margin coarsely 15-21-serrate or -dentate, teeth often incurved-tipped, apex acuminate or long acuminate; cystoliths punctiform. Inflorescences paniculate, 3-7 cm; female inflorescences with slender axes, often drooping in fruit. Male flowers in bud ca. 1.4 mm; perianth lobes connate 1/2 of length, puberulent. Female flowers: perianth lobes connate at 1/4 of lower part, dorsal-ventral lobes elliptic-ovate, 1.2-1.5 mm, sparingly setulose, lateral lobes narrowly elliptic, 2-3 × as long as the dorsal ones, Achene brownish gray, ovoid or narrowly ovoid, slightly compressed, 1-1.2(-1.4) mm, smooth, invested by persistent perianth lobes.

Nomenclature:

Scientific Name: Urtica dioica L.

Vernacular name(s): stinging nettle

Scientific family name: Urticaceae

Vernacular family name: nettle

Geographic Information

Moist places in forests, thickets, grasslands, stream banks; (500-) 2200-5000 m. E Gansu, Qinghai, NW Sichuan, W Xinjiang, Xizang [Afghanistan, C Himalayas; N Africa, Europe, North America].

Canada: Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland, Northwest Territories, Nova Scotia, Ontario, Prince Edward Island, Quebec, Saskatchewan, Yukon Territory.

Notes on Poisonous plant parts:

The stinging hairs on the stem, leaves, and flowers produce a painful sting. The hairs consist of a long shaft that narrows towards the point and has a small bulbous tip. The hair just below the tip is not silicified, unlike the rest of the hair, so that the tip is easily broken. A fine hollow shaft remains that can puncture the skin, through which secretions can enter (Mitchell and Rook 1979).

Toxic parts:

Hairs.

Notes on Toxic plant chemicals:

The stinging hairs of stinging nettle contain the compounds acetylcholine, histamine, and 5-hydroxytryptamine. Acetylcholine is found naturally in mammals and is involved in firing nerves, whereas histamine causes swelling (Mitchell and Rook 1979).

Toxic plant chemicals:

Acetylcholine, histamine, 5-hydroxytryptamine.

Animals/Human Poisoning:

Note: When an animal is listed without additional information, the literature (as of 1993) contained no detailed explanation.

Dogs

General symptoms of poisoning:

Death, dyspnea, pain, trembling, vomiting.

Notes on poisoning:

Hunting dogs in the United States were poisoned after massive exposure to the hairs of stinging nettle. Symptoms included trembling, pain, slobbering, dyspnea, and vomiting. Some dogs died 2-3 days after exposure without treatment (Anon. 1982).

Humans

General symptoms of poisoning:

Erythema.