Iris tenax Douglas ex Lindl.
Toughleaf iris, Tough-leaf iris, Oregon iris
Iridaceae (Iris Family)
USDA Symbol: irte
A tufted perennial with narrow, grass-like leaves and showy flowers on thin, wand-like stems to 14 in. tall. Leaves slightly exceed the flower stem in height. The flower of this species shows considerable variation in color, from white to deep purple. Large, delicate, lavender to deep purple (sometimes white, rarely yellow) flowers, commonly with dark violet veins, grow at top of short stalks in dense clumps of narrow, tough leaves about the same height. Flowers usually occur singly but sometimes in pairs.
In the Willamette Valley of Oregon these handsome flowers provide brilliant color displays along highways. Tenax, Latin for tenacious, refers to the tough leaves; Native Americans used fibers from the edges of the leaves of some western species to make strong, pliable rope and cord.
From the Image Gallery
Bloom InformationBloom Color: White , Pink , Yellow , Purple
Bloom Time: Apr , May , Jun
DistributionUSA: CA , OR , WA
Native Distribution: S.w. WA, s. to s.w. OR; intermittent to n. CA as var. klamathensis
Native Habitat: Open prairies; logged land; open areas in oak & conifer forests
Growing ConditionsWater Use: Medium
Light Requirement: Part Shade
Soil Moisture: Dry
CaCO3 Tolerance: Medium
Soil Description: Drier, well-drained soils.
Conditions Comments: Good rock garden plant. Does not spread quickly, but will form large clumps.
BenefitUse Wildlife: Hummingbirds
Warning: Some Iris species are known to be poisonous to humans and animals if eaten (especially the rhizome, or root), and it is likely that all irises contain toxins. Plant juices can cause blisters on the skin. POISONOUS PARTS: Rhizomes (thickened roots) and rootstocks, fresh or dry. Minor skin irritation when touched, low toxicity if ingested. Symptoms include nausea, vomiting, abdominal pain, diarrhea, elevated temperature following ingestion; skin irritation upon contact with seeds, rootstock, or cell sap. Toxic Principle: Irisin, iridin, or irisine. (Poisonous Plants of N.C.)
Conspicuous Flowers: yes
PropagationSeed Collection: Easily collected from the large capsules.
Seed Treatment: Not Available
Commercially Avail: yes
Find Seed or Plants
Find seed sources for this species at the Native Seed Network.
From the National Suppliers DirectoryAccording to the inventory provided by Associate Suppliers, this plant is available at the following locations:
Oregon Native Plant Nursery - Woodburn, OR
From the National Organizations DirectoryAccording to the species list provided by Affiliate Organizations, this plant is on display at the following locations:
Native Seed Network - Corvallis, OR
BibliographyBibref 928 - 100 easy-to-grow native plants for Canadian gardens (2005) Johnson, L.; A. Leyerle
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Recommended Species Lists
Find native plant species by state. Each list contains commercially available species suitable for gardens and planned landscapes. Once you have selected a collection, you can browse the collection or search within it using the combination search.View Recommended Species page
Additional resourcesUSDA: Find Iris tenax in USDA Plants
FNA: Find Iris tenax in the Flora of North America (if available)
Google: Search Google for Iris tenax
MetadataRecord Modified: 2009-03-04
Research By: TWC Staff