Range: Common and widespread in most of western Oregon and southern Washington west of the Cascade Mountains. There is a separate race in the Klamath Mountains of northern California.
Original material: seeds sent to England by explorer-naturalist David Douglas 1825
Key identifying features:
1. Floral tube between ovary and petals stout and short (about ¼ inch)
2. Narrow spathes separate, leaving ovary exposed
3. Style crests short and rounded
4. Plants form dense, compact clumps with narrow, light green leaves growing taller than the numerous flower stalks
5. Stalks usually bear single flowers, occasionally two
Flower color: Wide color range from purple and lavender to white, cream and yellow.
Habitat: Open or lightly shaded sites in open oak woodlands; unusual in coniferous forests unless they have been logged over.
Iris tenax clump, Douglas Co., Oregon [photo by the Ralstons]
Comment: Wild Iris tenax forms attractive, large clumps. Its cold hardiness should prove useful to hybridizers trying to adapt PCIs to cooler regions outside the Pacific coastal zone. Native Americans used the tough leaf fibers for snares, nets and other cordage.
Where their ranges overlap, I. tenax produces natural hybrids with I. douglasiana, I. chrysophylla and I. innominata. A yellow-flowered variety was once referred to as I. gormanii. A disjunct population near Orleans in California's Humbolt County has been called the Orleans iris, and named I. tenax klamathensis. It's funnel-shaped floral tube is longer (around ½ to ¾ inch) and the flowers are pale cream or light apricot, with a yellow patch on the petals and reddish-brown veins. It occurs in more shaded habitats than its northern relative.