# Trichome heads

> Trichome heads are the bulbous resin-filled tops of capitate glandular trichomes, where cannabis makes and stores nearly all its cannabinoids and terpenes; they are the raw material of hash.

- Canonical: https://genetixbay.com/knowledge/glossary/trichome-heads.html
- Also written: gland heads, trichome head, capitate heads, trichome gland heads
- Glossary category: Processing · Evidence: Established
- Status: Draft: awaiting expert review · Updated: 2026-10-31
- Licence: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/), attribute "GenetixBay cannabis glossary"

A trichome head is the glandular top of a [capitate stalked trichome](https://genetixbay.com/knowledge/glossary/capitate-stalked-trichome.md): a disc of secretory cells under a cuticle that swells into a storage cavity filled with resin. Livingston et al. (2020) showed that these stalked glands, which dominate mature flowers, are the main sites of [cannabinoid](https://genetixbay.com/knowledge/glossary/cannabinoid.md) and [terpene](https://genetixbay.com/knowledge/glossary/terpene.md) production. Head diameter on mature stalked trichomes is commonly in the range of roughly 50-120 µm, which is why hash makers grade them with [micron screens](https://genetixbay.com/knowledge/glossary/micron-bags.md).

## In practice

Everything solventless processing does is about separating heads from plant tissue. The cleaner the separation, the higher the cannabinoid content: pure heads are far richer than flower, because flower is mostly bract, leaf and stem by mass. That gap is also the logic behind the GenetixBay [potency ceiling](https://genetixbay.com/knowledge/glossary/potency-ceiling.md): dried flower can't approach the cannabinoid content of its isolated heads. Heads are fragile; warmth, handling and agitation break them and smear resin onto plant matter.

## Don't confuse with

- **Trichome (whole)**: includes the stalk; growers often mean the head.
- **Non-glandular trichomes**: [hairs](https://genetixbay.com/knowledge/glossary/pistil.md) with no resin.
- **Pistils**: the visible "hairs" of the flower, not [trichomes](https://genetixbay.com/knowledge/glossary/trichome.md).

## Myth check

Frost shows how many heads you can see, not how full they are. See [Mythbusters](https://genetixbay.com/knowledge/mythbusters.md).

## Related terms

[Kief](https://genetixbay.com/knowledge/glossary/kief.md), [Hash](https://genetixbay.com/knowledge/glossary/hash.md), [Bubble hash](https://genetixbay.com/knowledge/glossary/bubble-hash.md), [Full melt](https://genetixbay.com/knowledge/glossary/full-melt.md), [Potency ceiling](https://genetixbay.com/knowledge/glossary/potency-ceiling.md), [Solventless](https://genetixbay.com/knowledge/glossary/solventless.md)

## Read more

- [Cannabis plant biology: the parts and what they do](https://genetixbay.com/knowledge/basics/cannabis-plant-biology.md)
- [Trichome ripeness: clear, cloudy, amber, and what the evidence says](https://genetixbay.com/knowledge/harvest-cure/trichome-ripeness.md)

## Sources

1. Livingston SJ, Quilichini TD, Booth JK, et al. 2020. Cannabis glandular trichomes alter morphology and metabolite content during flower maturation. The Plant Journal 101(1):37-56. https://doi.org/10.1111/tpj.14516
2. Clarke RC. 1998. Hashish! Red Eye Press, Los Angeles (updated edition 2010).