Hazel
Corylus
- Known today as
- Corylus avellana.
- Kind
- Plant, in 1 older authority
- Constituents
- oleic acid, Cor a 1, taxifolin, and 1 more
- Earliest authority here
- Georgius Agricola (1494–1555)
- In other databases
- Plants of the World Online search · GBIF search · Wikidata search
Hazel: what was it used for?
The nuts as food; the catkins for coughs.
Hazel: what does modern science say?
A nutritious nut; no other medicinal effect.
Pharmacognosy & Toxicology
- Constituents
- Mechanism
- The nut is a food rich in monounsaturated fat and vitamin E; the catkins and bark are astringent. Hazelnut allergy, cross-reacting with birch pollen, is among the commonest tree-nut allergies of Europe.
- Toxic dose
- A food; anaphylaxis in the allergic.
- Standing
- A food; the leaf has a listing in French traditional use for venous complaints.
- Flinterman, A. E., et al. (2008). “Hazelnut allergy: from pollen-associated mild allergy to severe anaphylactic reactions.” Current Opinion in Allergy and Clinical Immunology 8. Verified against its record · doi:10.1097/aci.0b013e3282ffb145
The abstract of each source, beneath its citation. For Club members. About the Club or sign in.
Constituent names open the compound’s record at PubChem, and “ChEMBL” beside a name opens its record at ChEMBL, the European Bioinformatics Institute’s database of bioactive molecules. Where a mechanism line was checked against ChEMBL (ChEMBL 37, read 1 October 2026), the check is shown with the measured value and its source paper, or says plainly that nothing has been measured. Doses are as the references give them, for description only; this is not medical advice. Each source carries the result of its check against Crossref, PubMed, or the authority’s page: see Verification.
Hazel: what lore surrounds it?
The wood of wisdom in Irish tradition, and of the dowser’s rod, used to find water, metal, and hidden things.
Irish tradition held that hazels of wisdom grew over the sacred wells at the sources of Ireland’s chief rivers, dropping their nuts into the water; the salmon that ate them gained wisdom by the number eaten, which is why the salmon of wisdom gave Fionn mac Cumhaill all knowledge. Hazel was so sacred to the poets that burning it as common fuel was taboo, and its wood was the favored choice for both witches’ wands and dowsers’ rods.
Hazel: what did the older authorities say?
- Georgius Agricola
- Pictures miners seeking veins of ore with a forked hazel twig, the divining rod, though he doubted it.
Sources
- Agricola, G. (1556). De re metallica. Verified against its record · doi:10.5962/bhl.title.38150
- Druidry.org, “Hazel.” Book, seen in reviews
- Wikipedia, “Celtic sacred trees.” Book, not indexed
Verification
- Checked
- October 1, 2026
- Passes
- Every sentence read against its sources, in the pass over the remaining 343 entries
- The Standing line checked against the authority it names (EMA, WHO, FDA, CITES, Commission E)
- Every dated or regulatory claim checked by category across the database
- Sources
- 4 cited: 2 verified against its record, 1 book, seen in reviews, 1 book, not indexed. 1 with the abstract on file.
- Corrections
- None were needed.
What was checked, how, and what was found is set out on the Verification page. A checked source is one whose record was found; it does not make the entry medical advice.
Cite This Entry
Version 1 · first published September 25, 2026
- Chicago
“Hazel.” In Materia Medica, edited by B. C. P. Statema. Version 1. The Thinking Press, 2026–. Last modified September 25, 2026. https://thethinkingpress.org/materia-medica/hazel.
- MLA
“Hazel.” Materia Medica, edited by B. C. P. Statema, version 1, The Thinking Press, 25 Sept. 2026, thethinkingpress.org/materia-medica/hazel. Accessed 8 Oct. 2026.
- APA
Hazel. (2026, September 25). In B. C. P. Statema (Ed.), Materia medica (Version 1). The Thinking Press. Retrieved October 8, 2026, from https://thethinkingpress.org/materia-medica/hazel
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See Also
Sharing oleic acid, tannins
Olive oil and holy water · Chrism · Sweet almond, oil of · Blessed oil · Geum urbanum · Euphrasia officinalis · Cynoglossum officinale · Diascordium
Drawing on the same sources: Wikipedia
Nearby in the alphabet
Heartsease (the wild pansy of fields and banks, purple, white, and yellow) · Hawthorn (Crataegus monogyna) · Hemlock (Conium maculatum, of the carrot family) · Hartshorn (rasped, burnt, or distilled) · The Hand of Glory (holding a candle made from the fat of a hanged man) · Hamech, confection of (senna, polypody, and colocynth, among many other purgatives)
Historical description, not medical advice.