Perennial herb to 70cm tall. Densely tufted, from a short, thick rhizome; stems often branched. Leaves are long and fairly wide; sword-shaped. Blue/purple flowers with dark veins; sepals 5-6cm long, 3. Petals small, sharp-pointed.
Wet meadows, wetland edges, marshes, lake shores, at low to middle elevations.
Western blue iris (l. missourisensis) is another blue-flowered iris, but it has narrower leaves and larger blunt-tipped petals. It is an uncommon species, occasional on the BC coast.