stinging hair

plant anatomy

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Last updated

July 14, 2026

Quick Summary

Stinging hairs are specialized plant structures that secrete a stinging fluid. These hairs, found on plants like nettles, inject irritants such as formic acid into the skin upon contact. This causes a burning, tingling sensation and an itchy rash, though symptoms typically subside within 24 hours. Some plants, like the gympie gympie, possess more aggressive stinging hairs that can cause intense, debilitating pain and severe allergic reactions. The fluid within these hairs often contains compounds like histamine, acetylcholine, and serotonin.123

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angiosperm
Dermal tissue
…plants produce secretory (glandular) or stinging hairs (e.g., stinging nettle, Urtica dioica; Urticaceae) for chemical defense against herbivores. In insectivorous plants, trichomes have a part in trapping and digesting insects. Prickles, such as those found in roses, are an outgrowth of the epidermis and are an effective deterrent against herbivores.
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…plants produce secretory (glandular) or stinging hairs (e.g., stinging nettle, Urtica dioica; Urticaceae) for chemical defense against herbivores. In insectivorous plants, trichomes have a part in trapping and digesting insects. Prickles, such as those found in roses, are an outgrowth of the epidermis and are an effective deterrent against herbivores.
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Rosales
Characteristic morphological features
…nettle family) because of their stinging hairs. The stings are frequently a short-term irritant, but contact with some species can cause pain or numbness that lasts for several days. Fatalities have been reported in humans and domesticated animals from contact with the stinging hairs of Urtica ferox and some species…
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…nettle family) because of their stinging hairs. The stings are frequently a short-term irritant, but contact with some species can cause pain or numbness that lasts for several days. Fatalities have been reported in humans and domesticated animals from contact with the stinging hairs of Urtica ferox and some species…
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