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Blue flag

Iris versicolor

Also calledHarlequin blueflag · Northern blue flag

A wetland iris of north-eastern North America whose rhizome was a purgative, emetic and poultice among many First Nations, and later an ingredient in American Eclectic medicine. It has never been clinically tested, and the Abenaki regarded the plant as poisonous.

What it is used for

  • Constipation
    Traditional

    Cree, Creek, Iroquois and Ojibwa people used the root or plant as a purgative ('quick physic'); the Ojibwa also used it as an emetic. Not tested in trials.1

  • Liver health
    Traditional

    Cree used it to increase the flow of bile; Delaware healers used the root for liver disorders and, with wild hydrangea root, for gallstones.1

  • Wounds and cuts
    Traditional

    Poultices of crushed root were applied to wounds, sores, swellings and bruises (Tête-de-Boule, Chippewa, Meskwaki, Omaha, Micmac), and to burns.1

  • Tête-de-Boule and Meskwaki people applied root poultices to burns.1

  • Delaware healers used the root externally and internally for rheumatism.1

  • Earache
    Traditional

    Omaha and Ponca dropped pulverised rootstock mixed with water or saliva into the ear for earache.1

How it is prepared

poultice

Fresh rhizome crushed or pulverised, sometimes mixed with flour, and laid on sores, swellings, burns or painful areas (Indigenous North American records).

Wounds and cuts · Burns and sunburn

decoction

Root decoction taken as a purgative in Ojibwa practice; no reliable dosing is recorded.

Constipation

Amounts are as recorded by the named source, not a recommendation.

Safety

Pregnancy
Insufficient data
Breastfeeding
Insufficient data

Side effects

  • Purging and vomiting (its traditional purpose)

Toxicity

Recorded as poisonous by the Abenaki and used by several peoples as a strong emetic and purgative. No modern toxicology or safe dose was found, so internal use cannot be assessed.

In the healing traditions

  • Indigenous North American

    Blue flag

    Purgative and emetic (Cree, Creek, Iroquois, Ojibwa); bile and liver remedy and for kidney disorders, rheumatism and 'scrofula' (Delaware); poultices for sores, burns, swellings and bruises (Chippewa, Meskwaki, Omaha, Micmac); earache and eye medicine (Omaha, Ponca); cholera (Micmac, Penobscot). The Abenaki considered the plant poisonous.

    Densmore 1928; Smith 1928, 1932; Gilmore 1919; Tantaquidgeon 1942, 1972 (via NAEB)

  • Western herbalism

    Iris versicolor (Eclectic medicine)

    One of several herbs in a 1908 Eclectic case report of rectal cancer treatment collated by a scoping review of historical texts; the report is anecdotal.

Active compounds

iridals (e.g. 26-hydroxyiridal, 22,23-dihydro-22-methyleneiridal)
triterpenoids reported from I. versicolor rhizomes
iriflophenone and (iso)flavonoids
benzophenone and flavonoid constituents; leaf/rhizome extracts inhibited oral bacterial biofilms in vitro

History

Ethnographers from Holmes (1884, Cree of Hudson Bay) to Densmore, Smith, Gilmore and Tantaquidgeon recorded the root in the medicine of nearly twenty North American peoples. It also appears among the herbs of an Eclectic physician's 1908 case report.

Sources

  1. 1.Native American Ethnobotany Database (BRIT): Iris versicolor
  2. 2.Imtiaz I et al. Traditional and contemporary herbal medicines in management of cancer: a scoping review. J Ayurveda Integr Med 2024
  3. 3.Mykhailenko O et al. The state of knowledge of the primary and secondary metabolites of the Iris genus. Chem Biodivers 2026
  4. 4.Hoang L et al. Phytochemical composition and in vitro biological activity of Iris spp.: inhibition of oral bacterial biofilms. Antibiotics 2020 (abstract)
  5. 5.GBIF: Iris versicolor L.

Reference, not prescription. Nothing here is medical advice. Herbs can interact with medicines and be dangerous in pregnancy; tell your doctor or pharmacist about anything you take.