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Bulbs, Perennials > Iris > Iris missouriensis > Iris missouriensis

Iris missouriensis

Western Blue Flag, Rocky Mountain Iris

Origin:  The northern edge of its range in Canada is southwestern Alberta. In this area it is found in a narrow band 27 km by 10 km. It is a threatened species in Canada. Populations also occur in neighbouring British Columbia and near Victoria but is is suspected that these are transplanted populations from Alberta or possibly Iris setosa. It is also found in the United States of America from Montanna to Mexico. It is found in large populations in the Rocky Mountain states and Great Plains and be may also be found in large localized populations within these areas. It is found growing in association with Potentilla fruticosa and Festuca scabrella in the drier upland zones and on the lowland wet areas with Deschampsia cespitosa. Other plants that growing in association Carex spp., Calamagrostis inexpansa, Allium schoenoprasum, Potentilla anserina and Zisia aptera. In 2010 Iris missouriensis was listed by the Committee on the Status of Endangered Wildlife in Canada as a plant of special concern.
Bulbs, Perennials
30 - 80 cm
1 m
Description and Growing Information
Flowering Period
In its natural habitat increased grazing and trampling by livestock sees an increase in its spread and vigour.
It occurs in moist meadows and edges of streams that are typically wet in the spring but then dry towards summer.
Leaf Description
Pale blue-green leaves are 10 - 40 cm long and 2 - 5 cm wide, originating from the base and folded along their length. The previous years leaves persist on the plant.
Flower Description
Flowers 2 - 4 per stem, pale blue to blue-violet, each with 9 petal-like segments forming 3 sepals, 3 petals and 3 enlarged styles. Purple veins radiate from a bearded yellow spot on each of the sepals, which are spreading, recurved and are 4 -6 cm long. A white-flowered form exists that that has little or no veining
Fruit Description
The seed capsule is 2 -5 cm long and at maturity splits along three sides to release dark brown seeds.
Division of rhizomes is the easiest.
Ethnobotanical Uses (Disclaimer)
It has been used by aboriginal people for its medicinal properties. Uses have included adding dried rootstock to a smoking mixture to induce nausea or chewed raw to relieve toothaches. It may also have anti-viral and anti-cancer properties. The seed can be roasted as a coffee substitute.