Michigan designated the dwarf lake iris (Iris lacustris) as the official state wildflower in 1998. This unique and rare wildflower is found only on the coastlines of northern Lake Michigan and northern and eastern Lake Huron, one small site on the southern shore of Lake Superior, and a few isolated islands of the Great Lakes (it thrives in low wet spots near beaches, not on them).

Listed as threatened in Michigan, this iris is much smaller than other iris - growing only 6-8 inches tall. The dwarf lake iris has a flower only 1.5 - 2 inches in diameter (almost always purple in color, with an occasional white mutant) and blooms for only about one week during the year.

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Links:

State Flowers - 50 States List
National Flower