Forest Preserve District of Cook County, Illinois
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The Blue Flag and the Iris Family
Nature Bulletin No. 596-A   March 20, 1976
Forest Preserve District of Cook County
George W. Dunne, President
Roland F. Eisenbeis, Supt. of Conservation

In Greek mythology, when Zeus or Hera wanted to speak to mortal men they called up lovely Iris, goddess of the rainbow, who hurried heavenward and brought their messages back to earthlings over her bridge of color. Quite naturally, a group of plants whose large spectacularly shaped flowers run the entire gamut of colors has been named after her and her rainbow. The fleur-de-lis, a formal design based on the iris blossom, is best known as the insignia of the kings of France from the 12th century down to the time of Napoleon. Our language is rich in words using the Greek name for rainbow to express color.

The Blue Flag, the only native iris of the Chicago region, grows in circular clumps on the edges of sloughs, ponds, and streams in many Cook County forest preserves. The plant appears to be pressed and flattened with two rows of slender leaves on a central flower stalk two or three feet tall. Both sides of each leaf are undersides, because it is folded length-wise with the two halves of the upper surface stuck together except at the base where they straddle the base of the leaf next above.

The large showy blue or violet flower appears in June. The three petals stand erect. The three equally colorful broad sepals droop, or "flag, " making fine landing fields for honeybees, bumble bees and bee-like flies which follow bright guide lines leading to the nectar well. A special mechanism insures cross-pollination. A long petal-like branch of the pistil with a sticky flap on its tip wipes pollen from an in-coming bee's back. A little deeper into the flower, the bee brushes against an anther and gets a fresh load of pollen. A s it backs out, the flap curls upward, thus protecting the iris from its own pollen. The flower is followed by a pod which sheds D-shaped seeds covered with a corky layer that prevents rotting in water.

One other species, the Copper Iris, is found in southern Illinois but, farther south, in the lowlands of Louisiana, are a hundred native kinds. Clumps of two Old World irises, the Dwarf and the German, are sometimes found growing along roadsides in this region where they have escaped from home gardens and cemeteries. Iris fanciers cultivate over a thousand varieties and hybrids, drawn from many parts of the world, in a bewildering array of colors, sizes and fantastic shapes .

The delicate little Blue-eyed Grasses of our prairies, meadows and dry hillsides also belong to the Iris Family. Deep blue, light blue or white, their small six-pointed stars seem to arise from the edges of flattened blades of grass.

The Gladiolus (meaning Little Sword) is a member of the iris family. Like the iris, these are favorites of flower gardeners who grow thousands of different cultivated varieties. Either as a hobby, or as a business, the growers of Gladiolus and Iris have organized dozens of societies to promote their special interest.

Very few of the iris family are of much economic importance. The roots of the blue flag are mildly poisonous to cattle and certain persons may get a skin rash from handling them. Some European irises are the source of orris root, which gives a pleasant violet odor to tooth powders, perfumes and sachets. A piece of the root, called an iris "finger, " is chewed by teething babies. An early spring relative gets its name, Crocus, from the Greek word for saffron -- its dried orange- colored pungent stigmas which are used to color and flavor food.

The iris is the poor man's orchid.

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