trichome

References

Images

Floral trichome

New Zealand tree nettle

Botanical illustration showing three panels of fern leaf surface structures: panel A displays various hair types including glandular, stellate, and pointed hairs; panel B shows different scale types such as typical, clathrate, and peltate scales with details of their attachment and cell walls; panel C depicts a young uncurling fern leaf, or crosier, highlighting circinate vernation, surface scales, and labeled plant parts.

trichome

plant anatomy

Also known as: hair, plant hair

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Last updated

July 14, 2026

Quick Summary

Floral trichome — Floral trichome Floral trichomes (plant hairs) on the buds and sepals of thyme flowers (Thymus vulgaris).

Trichomes are filamentous outgrowths, primarily epidermal hair structures found on plants. They originate from epidermal cells and can be either unicellular or multicellular.12

Trichomes serve various functions:
* Protection: They can increase the reflection of solar radiation, helping plants reduce internal temperatures and water loss, especially in arid conditions. Some trichomes also help deter herbivores or protect against predation by insects.2
* Absorption: In certain plants, like epiphytic bromeliads, trichomes absorb water and minerals.2
* Secretion: Glandular trichomes produce and secrete substances such as oils, resins, or digestive juices.2
* Defense: Some trichomes, like stinging hairs, provide chemical defense.2

Trichomes are valuable for identifying and classifying different fern species due to their diverse forms.3

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fern
Surface structure
…consisting of hairs, known as trichomes, or scales; these are so distinctive that they are valuable in identification and classification. The indument includes such diverse types of epidermal emergences as simple glands (unbranched one- to several-celled trichomes with a headlike cluster of secretory terminal cells), simple (unbranched) nonglandular trichomes, dendroid…
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…consisting of hairs, known as trichomes, or scales; these are so distinctive that they are valuable in identification and classification. The indument includes such diverse types of epidermal emergences as simple glands (unbranched one- to several-celled trichomes with a headlike cluster of secretory terminal cells), simple (unbranched) nonglandular trichomes, dendroid…
Read More

stinging nettle
The stinging trichomes of the leaves and stems have bulbous tips that break off when brushed against, revealing needlelike tubes that pierce the skin. They inject a mix of acetylcholine, formic acid, histamine, and serotonin, causing an itchy, burning rash in humans and other animals that may…
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The stinging trichomes of the leaves and stems have bulbous tips that break off when brushed against, revealing needlelike tubes that pierce the skin. They inject a mix of acetylcholine, formic acid, histamine, and serotonin, causing an itchy, burning rash in humans and other animals that may…
Read More

sundew
Physical description
…is covered with flexible gland-tipped trichomes (plant hairs) that exude a sticky substance to attract and entrap insects and other small prey. Trapped prey are engulfed in a web of the sticky glands, colloquially known as tentacles, and digested by enzymes. Following digestion, the leaf unfurls to reset the trap.
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…is covered with flexible gland-tipped trichomes (plant hairs) that exude a sticky substance to attract and entrap insects and other small prey. Trapped prey are engulfed in a web of the sticky glands, colloquially known as tentacles, and digested by enzymes. Following digestion, the leaf unfurls to reset the trap.
Read More