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Iris missouriensis - Rocky Mountain iris

Scientific Family
Iridaceae
Synonyms
Iris longipetala, Iris pariensis, Iris tolmieana, Iris missouriensis var. arizonica, Iris missouriensis var. pelogonus
Other common names
snake lilly
water flag
fleur-de-lis
western blue flag
Plant type
Forbs and Subshrubs
Origin
Native
Lifecycle
Perennial
Height
To 2 feet
Riparian
Yes

Upright perennial that grows in clumps with green sword-shaped leaves and large, showy, lilac-blue flowers with pale throats.

Rhizomatous erect perennial, stems slender, simple or branched. Leaves basal, flat and smooth. Pale blue to lavender flowers terminal on stout stalks, tubular with short lobes. Seed capsules contain numerous brown wrinkled seeds.

Habitat

Wet meadows, streambanks, seeps, aspen woods, montane habitats.

Plant Community
Montane Conifer Forest
Riparian
Low elevation
6000
High elevation
9500

Flower Characteristics

Flowers are pale blue to violet and streaked with white. The flowers are composed of 3 narrow, erect petals and 3 wider sepals that curve downward. Flowers are to 4 inches wide at the top of a stout, leafless stem. 1 to 4 flowers per stem.

Flower color
Blue to purple
Flower shape
Irregular
Tubular
Yes
First bloom month
May
Last bloom month
September
Flower clusters
None

Leaf and Stem Characteristics

Green, sword-shaped leaves that grow in clumps. Leaves are basal and on the lower stems.

Leaf type
Simple
Leaf color
Dark green
Leaf shape
Narrow
Leaf margin
Smooth
Leaf attachment
Basal & Alternate
Leaves clasp
No
Leaf hairs
None
Spines
No

Fruit and Seed Characteristics

Capsule is 3-celled containing many seeds.

Fruit type
Capsule
Fruit color
Green to brown

Seeds are obovate, dark to reddish brown and minutely wrinkled.