Northern Ontario Plant Database
Iris versicolor L.
En: blue flag, iris, poison flag, larger blueflag, harlequin blueflag
Iridaceae (Iris Family)
General: A perennial forb of wet habitats with large, showy, purple flowers; plants to 1 m tall, with long narrow leaves and flowering stems arising from a thick rhizome.
Leaves: Basal, simple, smooth (glabrous), parallel-veined. Blades linear-lanceolate to sword-shaped (ensiform), stiff, ascending, to 1 m long, 0.5–3 cm wide; often purplish at the sheathing base, gradually tapering to a sharply pointed (acuminate) tip, margins entire. Leaves arranged in 2 rows (2-ranked), folded lengthwise near the base and equitant – with each leaf base folded around the next younger leaf. Flowering stems bear 1–2 leaves.
Flowers: Bisexual; flowers terminal, solitary or in a few-flowered cyme, each flower subtended by a papery bract; perianth parts united into a short tube, to 1.2 cm long, above the ovary. Sepals 3, obovate, 4–7 cm long, purple to bluish-purple, marked with white towards the base and a yellow, slightly bearded patch, each sepal heavily veined with darker purple and abruptly narrowed to a clawed base; petals 3, oblanceolate, 2–4.5 cm long, purple, erect, alternating with the sepals; stamens 3, situated above the sepals, anthers linear; ovary inferior; the style divided into 3 petal–like branches that arch over the anthers, hiding them from view; a narrow flap of stigmatic tissue is situated near the recurved end of each style branch. Flowers bloom in mid summer.
Fruit: A smooth, 3-chambered capsule, 1.5–6 cm long, green when young, turning brown. Capsules mature in August to September.
Habitat and Range: Marshes, streambanks, wet meadows and shorelines. Iris versicolor is native to northeastern North America, extending from Newfoundland and Labrador west to Manitoba. In Ontario, it occurs as far north as the Fawn River, 54� N, 89� W (Scoggan 1978).
Similar Species: The dwarf lake iris, Iris lacustris, found in coastal areas of Manitoulin Island, the Bruce Peninsula, Michigan, and Wisconsin, is much shorter than the common blueflag, growing to only 1 dm in height. It is restricted to shorelines of the upper Great Lakes with limestone bedrock. The dwarf lake iris has been adopted as the State Flower of Michigan.
Here are several excellent images of Iris lacustris from Michigan, posted on the Michigan Wildflowers website.
Internet Images: The Iris versicolor webpage from the Gallery of Connecticut Wildflowers, a website of the Connecticut Botanical Society.
Traditional uses for Iris versicolor are provide in the Medicinal Herb Garden website by Agriculture and Agri-foods Canada. Note that although used medicinally, this plant, especially the rhizome, contains compounds that can severely irritate the gastro-intestinal tract and/or cause dermatitis.
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