Arctagrostis is a small genus of perennial grasses in the family Poaceae, comprising one or two species adapted to Arctic and subarctic climates. The genus is distributed across the high latitudes of the Northern Hemisphere, with populations recorded in Scandinavia (Finland, Norway, Svalbard), European and Asiatic Russia, Kazakhstan, Mongolia, Siberia, the Russian Far East, Alaska, Greenland, and much of northern Canada.
The best-known species, Arctagrostis latifolia (wideleaf polargrass), is a rhizomatous, sod-forming grass that tolerates waterlogged tundra soils, fens, and moist Arctic meadows. Its broad leaf blades (broad relative to other Arctic grasses) distinguish it from related genera. Arctagrostis arundinacea, recorded from Siberia, the Russian Far East, and parts of western North America, is sometimes treated as a distinct species and sometimes synonymised.
The genus was formerly broader; Arctagrostis humilis is now placed in Dupontia (as Dupontia fisheri). Within Poaceae, Arctagrostis belongs to a lineage of cool-season grasses that thrive under the extreme photoperiod and temperature conditions of the Arctic, making it ecologically significant as a component of circumpolar tundra vegetation.
Distribution
Arctagrostis has a circumpolar Arctic and subarctic distribution. A. latifolia occurs across Finland, Norway, Svalbard, Russia (European and Asiatic), Kazakhstan, Mongolia, Alaska (including the Aleutians), Greenland, and northern Canada (Yukon, Northwest Territories, Nunavut, Alberta, Manitoba, British Columbia, Labrador, Ontario, and Québec). A. arundinacea is recorded from Siberia, the Russian Far East, Alaska, and parts of western Canada.
Ecology
The genus inhabits moist to wet tundra habitats — fens, wet meadows, stream banks, and waterlogged lowland tundra — across the Arctic and subarctic zone. These grasses are cold-tolerant perennials that persist under extreme photoperiod conditions and freeze–thaw cycles, and they contribute to ground cover in circumpolar tundra plant communities.
