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SHOWING RECORD: 19 of 24   Western Blue-Flag
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image: Western Blue-Flag
Photograph by Darrell Gulin/Corbis
Western Blue-Flag
(Rocky Mountain Iris)

Iris missouriensis

First Noted by Expedition
July 6, 1806, in Powell County, Montana.

Large, delicate, pale blue or blue-violet flowers, often with purple veins, bloom at the top of stout, leafless (or with one short leaf) stalks that grow from dense clumps of flexible, tough, sword-shaped leaves. Flowers 3-4 in (7.5-10 cm) wide. Height: 8-20 in (20-50 cm).

Meadows and stream banks, always where moisture is abundant until flowering time.

British Columbia to southern California, east of the Cascade Mountains and Sierra Nevada (and on islands in Puget Sound); east to southern New Mexico, Colorado, and North and South Dakota.

The only native species east of the Cascade Mountains and the Sierra Nevada, it often forms dense, large patches in low spots in pastures, where the tough leaves are avoided by cattle.

Species information from enature.com

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