# What are terpenes in cannabis?

> Terpenes are the volatile aroma compounds cannabis makes in its glandular trichomes, alongside cannabinoids; myrcene, limonene, caryophyllene, pinene and terpinolene are common. Total terpenes average about 2% of flower weight. In nearly 90,000 US lab results, THC-dominant flower fell into three terpene groups. The 'gas' smell comes mostly from trace sulfur compounds, not terpenes. Terpenes evaporate, so drying and storage matter.

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- Topic: Basics · Type: Definition
- Evidence: Established · Status: Draft: awaiting expert review
- Full article: [Why everything tastes the same: the evidence that commercial cannabis is converging](https://genetixbay.com/knowledge/genetics-history/why-everything-tastes-the-same.md)
- Also asked as: What do terpenes do? | Terpenes meaning | Why does weed smell? | What are the main terpene profiles in cannabis? | Does irradiation destroy terpenes?
- Updated: 2026-10-31 · Licence: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/), attribute "GenetixBay Knowledge Base (genetixbay.com/knowledge)"

## Short answer

[Terpenes](https://genetixbay.com/knowledge/glossary/terpene.md) are the volatile compounds that give cannabis most of its smell and taste: [myrcene](https://genetixbay.com/knowledge/glossary/myrcene.md), [limonene](https://genetixbay.com/knowledge/glossary/limonene.md), [β-caryophyllene](https://genetixbay.com/knowledge/glossary/beta-caryophyllene.md), [pinene](https://genetixbay.com/knowledge/glossary/alpha-pinene.md), [terpinolene](https://genetixbay.com/knowledge/glossary/terpinolene.md) and many more. The plant makes them in its glandular [trichomes](https://genetixbay.com/knowledge/glossary/trichome.md), alongside [cannabinoids](https://genetixbay.com/knowledge/glossary/cannabinoid.md). Total terpenes average about 2% of flower weight. *Established* chemistry.

## Why

Terpenes are made in the resin glands. Terpene synthase enzymes in the trichomes build [monoterpenes](https://genetixbay.com/knowledge/glossary/monoterpene.md) (10 carbons, lighter and more volatile) and [sesquiterpenes](https://genetixbay.com/knowledge/glossary/sesquiterpene.md) (15 carbons, heavier) from shared precursors [1]. Which synthase genes a plant carries largely sets its profile [1][5].

Commercial flower clusters into a few profiles. In 89,923 US lab results, THC-dominant flower fell into three terpene groups: caryophyllene–limonene, myrcene–pinene and terpinolene–myrcene, with the first two holding 87.4% of samples [2].

Not every smell is a terpene. The fuel-like "gas" note comes mostly from trace prenylated [sulfur](https://genetixbay.com/knowledge/glossary/sulfur.md) compounds, detected at tiny levels [3].

Terpenes are fragile. Monoterpenes evaporate and oxidise with heat, air and time. [Gamma irradiation](https://genetixbay.com/knowledge/glossary/irradiation.md) cut some volatile monoterpenes by 10–20%, up to 38% for one compound [4]; slow drying and cool, dark, airtight storage keep more.

Labels track terpenes loosely. "Indica" and "sativa" tags associate with a few terpenes, not with genome-wide ancestry [5].

## The numbers

| Terpene | Class | Common aroma |
|---|---|---|
| Myrcene | Monoterpene | Earthy, musky |
| Limonene | Monoterpene | Citrus |
| α- and β-pinene | Monoterpene | Pine |
| Terpinolene | Monoterpene | Fresh, herbal, "haze" |
| β-caryophyllene | Sesquiterpene | Pepper, spice |
| Humulene | Sesquiterpene | Woody, hoppy |
| Total terpenes | — | ~2% of flower weight on average |

## What to do

1. Read the terpene section of a [certificate of analysis](https://genetixbay.com/knowledge/glossary/coa.md), not just [THC](https://genetixbay.com/knowledge/glossary/thc.md).
2. Dry slowly, about 18–21 °C (64–70 °F) and 55–62% [RH](https://genetixbay.com/knowledge/glossary/relative-humidity.md) for 7–14 days.
3. Cure and store in full, airtight, dark jars; skip [humidity packs](https://genetixbay.com/knowledge/glossary/humidity-pack.md), which rob terpenes.
4. Pheno-hunt by nose and keep unusual profiles.

## Common mistakes

- Assuming a terpene predicts an effect. Effects are reported, not promised.
- Fast, warm drying that drives off monoterpenes.
- Believing very high total-terpene claims without a lab name and date.

## Related

- Full article: [Why everything tastes the same](https://genetixbay.com/knowledge/genetics-history/why-everything-tastes-the-same.md)
- Answers: [why buds lose their smell](https://genetixbay.com/knowledge/answers/buds-lost-their-smell.md) · [strain vs cultivar](https://genetixbay.com/knowledge/answers/strain-vs-cultivar.md)
- Article: [Irradiated cannabis](https://genetixbay.com/knowledge/harvest-cure/irradiated-cannabis.md)
- Terms: [terpene](https://genetixbay.com/knowledge/glossary/terpene.md) · [terpene profile](https://genetixbay.com/knowledge/glossary/terpene-profile.md) · [volatile sulfur compounds](https://genetixbay.com/knowledge/glossary/volatile-sulfur-compounds.md)

## Follow-up questions

**What are the main terpene profiles in cannabis?** The main terpene profiles in commercial THC-dominant cannabis are three groups found in a 2022 study of US lab data: caryophyllene–limonene, myrcene–pinene and terpinolene–myrcene. The first two held 87.4% of samples, and terpinolene-led flower was the smallest group. Rarer dominants include ocimene and the sesquiterpene alcohols guaiol and eudesmols.

**Does irradiation destroy terpenes?** Irradiation does not destroy terpenes, but it can reduce them. Some studies found no significant terpene change, while others measured 10–20% losses of volatile monoterpenes such as myrcene, ocimene and terpinolene, up to 38% for one compound, with sesquiterpenes barely changing. In one study, months of normal storage cost more terpenes than the treatment did.

**Do terpenes change the effects of cannabis?** Whether terpenes change the effects of cannabis is not settled. Aroma is linked with reported subjective effects in some consumer studies, and 'indica' and 'sativa' labels track only a few terpenes, not effects. No controlled evidence shows a given terpene reliably produces a given effect, so treat terpene-based effect claims as reported experience, not a promise.

## Sources

1. Booth JK, Bohlmann J. 2019. Terpenes in Cannabis sativa – From plant genome to humans. Plant Science 284:67-72. https://doi.org/10.1016/j.plantsci.2019.03.022
2. Smith CJ, Vergara D, Keegan B, Jikomes N. 2022. The phytochemical diversity of commercial Cannabis in the United States. PLOS ONE 17(5):e0267498. https://doi.org/10.1371/journal.pone.0267498
3. Oswald IWH, Ojeda MA, Pobanz RJ, et al. 2021. Identification of a new family of prenylated volatile sulfur compounds in cannabis revealed by comprehensive two-dimensional gas chromatography. ACS Omega 6(47):31667-31676. https://doi.org/10.1021/acsomega.1c04196
4. Hazekamp A. 2016. Evaluating the effects of gamma-irradiation for decontamination of medicinal cannabis. Frontiers in Pharmacology 7:108. https://doi.org/10.3389/fphar.2016.00108
5. Watts S, McElroy M, Migicovsky Z, et al. 2021. Cannabis labelling is associated with genetic variation in terpene synthase genes. Nature Plants 7:1330-1334. https://doi.org/10.1038/s41477-021-01003-y