| STATUS Western blue flag occurs in the Foothills Grassland Natural Region, an area stretching from the western edge of the Milk River Ridge to the foothills west of Carway and north to Okotoks, Alberta. Of the 750 km� portion of the Foothills Grassland Natural Region in which western blue flag may have occurred prior to European settlement, less than 100 square km remains in an uncultivated condition. Only a small fraction of the natural habitats in the Natural Region are suitable for western blue flag. Surveys in the late 1980s in this area found only six populations of western blue flag, with a total of fewer than 7500 stems. Since then, a seventh population has been identified, and total numbers are now estimated at 7800 stems. Two sites near Carway and one at Whiskey Gap have significant populations. Two more sites have very small populations. These sites are all on private property and have no legal protection. The sixth site has some protection because of its location in Police Outpost Provincial Park. In addition, western blue flag has disappeared from at least two sites where it once occurred. Western blue flag occurs at the northern edge of its range in southwestern Alberta, in a narrow band, 27 km by 10 km, paralleling the international border. It is considered rare in Alberta. The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) has designated the western blue flag as threatened in Canada. Alberta contains the only known populations of this species in Canada. Western blue flag commonly occurs from Montana south to Mexico, and although it is abundant in portions of the Rocky Mountain states and Great Plains, there are large areas of its range where it is very localized. It occurs on moist meadows and streambanks that are wet early in the spring but are often dry later in the summer. DISCRIPTION The western blue flag (Iris missouriensis) is a member of the Iris Family or Iridaceae. The origin of the name is Greek; golden-winged Iris was the Greek goddess of the rainbow, and a messenger of Hera, queen of the gods. The flowers usually occur two (up to four) to a stem. Each pale blue or blue-violet flower has nine petal-like segments in the form of three sepals, three petals and three enlarged styles. There are purple veins radiating from a bearded yellow spot on each of the outer segments (sepals) which are spreading and often recurved and are 4 to 6 cm long. The inner segments (petals) are erect or arch upward. The styles curve down over the sepals. The white-flowered form is golden-throated with little or no veining. The seed capsule is oblong, about 2-5 cm long. When mature it splits along three sides to release dark brown seeds. The plant is 30-60 cm tall, with pale blue-green leaves 10-40 cm long and 5-10 mm wide. The leaves grow from the base of the plant and are folded in half lengthwise. The flowering stems are leafless or may have one leaf. The previous year's leaves are persistent. The roots grow from a thickened, dark-coloured rhizome (rootstock). REPRODUCTION Western blue flag is a long-lived perennial with a thick underground rhizome that enables populations to maintain themselves over long periods of time. The rootstock allows the plant to withstand heavy trampling and to spread rapidly when competition from other plants is reduced. The flowers, which are produced only in the most favourable conditions of reduced competition and sufficient water, are cross-pollinated by insects, usually bees. The seeds are released when the capsule opens and is shaken by the wind or passing animals. The seeds fall close to the plant where the habitat is likely to be suitable for germination and growth. HABITAT Most of the sites suitable for western blue flag are on level or slightly sloping ground where there is abundant subsurface moisture. Western blue flag occurs at the edges of wet meadows or seepage springs, where the soil is damp in the spring but well drained and drier by midsummer. Stands are often found close to willow thickets around moist depressions or along minor drainages. Western blue flag prefers full sun. The habitat range suitable for western blue flag lies within a narrow region of moist meadows in a transition zone between drier upland slopes supporting shrubby cinquefoil and rough fescue (Potentilla fruticosa/Festuca scabrella), and wet areas dominated by tufted hair grass (Deschampsia cespitosa). Other plants often associated with western blue flag include sedges (Carex spp.), northern reed grass (Calamagrostis inexpansa), wild chives (Allium schoenoprasum), silverweed (Potentilla anserina), and heart-leaved Alexanders (Zizia aptera). HUMAN USE Irises have been valued throughout the ages. They have been used as symbols of royalty, the three parts of the flower representing wisdom, faith and courage. The Alberta Native Plant Council, a conservation group dedicated to protecting our native vegetation, has chosen the western blue flag as its emblem, and as a symbol of Alberta's rare and native plants. Dramatic and vulnerable, flowers like the western blue flag are valued by photographers and educators who wish to promote the protection of native plants. Western blue flag has been used medicinally by aboriginal people; the rootstock was added to a smoking mixture to induce nausea or chewed raw to relieve toothaches. Research is now being conducted on western blue flag to investigate its possible antiviral and anticancer properties. |
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| PLANTS INFO - 1 |