Rocky mountain iris, western blue flag, wild iris
Parts of most of the western states
Between 8 and 20 inches
Streambanks, meadows, woodland margins; moist locations, from near sea level to 11,000 feet
Thin, linear, basal, up to 20 inches long but less than half an inch wide
Iris missouriensis is (in the West) the only iris species east of the Sierra Nevada and the Cascades, and so is easily identified over most of its range. The long, linear, upwards-pointing leaves grow only at the base; the leafless stems rise to heights of up to 20 inches - similar to the longest leaves - and usually bear one or two flowers (occasionally up to four).
Flowers are blue to pinkish purple, consisting of 3 large, oblanceolate sepals (over 2 inches long), curved backwards, between which are 3 somewhat shorter petals, more upright. Sepals often have yellowish patches at the center, and a purple veined pattern around the edge. The middle of the flower contains a group of stamens and a branched style.