Several violet-blue flowers with intricately veined, yellow-based sepals on a sturdy stalk among tall, sword-like leaves rising from a basal cluster.

2 1/2- 4" wide; sepals 3; petals , narrower, erect; styles 3, 2-lobed, arching over sepals; stamens 3, hidden under styles.

8-31" long, 1/2-1" wide, pale green to grayish.

None

2-3'.

May-August.

Swamps, marshes, and wet shorelines.

This is a Showy native iris of the northeastern wetlands. Insects attracted to the sepals must crawl under the tip of a style and brush past a stigma and stamen, thus facilitating pollination. The rhizome is poisonous, but it was dried and used in small amounts as a cathartic and diuretic by Native Americans and colonists. A similar wetland species, occurring from Ontario and Quebec south to Florida and Texas, is Southern Blue Flag (I.virginica); it is a smaller plant, to 2' tall,with bright green leaves that often lie o the ground of float on water. A coastal,brackish-water species, Slender blue flag (I.prismatica), has extremely narrow, grass-like leaves less than 1/4" wide; it occurs in Ontario and Georgia and Tennessee. The common name Flag is from the Middle English flagge, meaning "rush" or "reed."