''Salix polaris'', the polar willow, is a species of

willow Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist so ...

with a circumpolar distribution in the high

arctic The Arctic ( or ) is a polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenland), Finland, Iceland, N ...

tundra In physical geography, tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. The term ''tundra'' comes through Russian (') from the Kildin Sámi word (') meaning "uplands", "treeless mou ...

, extending north to the limits of land, and south of the Arctic in the mountains of

Norway Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and the ...

, the northern

Ural Mountains The Ural Mountains ( ; rus, Ура́льские го́ры, r=Uralskiye gory, p=ʊˈralʲskʲɪjə ˈɡorɨ; ba, Урал тауҙары) or simply the Urals, are a mountain range that runs approximately from north to south through western ...

, the northern

Altay Mountains The Altai Mountains (), also spelled Altay Mountains, are a mountain range in Central and East Asia, where Russia, China, Mongolia and Kazakhstan converge, and where the rivers Irtysh and Ob have their headwaters. The massif merges with the ...

Kamchatka The Kamchatka Peninsula (russian: полуостров Камчатка, Poluostrov Kamchatka, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and west ...

, and

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

.Salicaceae of the Canadian Arctic Archipelago
''Salix polaris''
Plants of British Columbia
''Salix polaris''
/ref>Den Virtuella Floran

/ref>

Description

One of the smallest willows in the world, it is a prostrate, creeping dwarf shrub, only high, and has underground branches or runners in the uppermost soil layers. The leaves are rounded-ovate, 5–32 mm long and 8–18 mm broad, dark green with entire margins. It is dioecious, with separate female and male plants. The

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s are grouped in short catkins each bearing only a few flowers. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering. Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...

is a brownish and hairy capsule. The long runners with freely rooting stems creep in mats of mosses and lichens, which keeps them together and protects them from the wind. It grows as well in open gravel as in closed vegetation.Blamey, M. & Grey-Wilson, C. (1989). ''Flora of Britain and Northern Europe''.

Fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

remains of the species from the

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...

ice age An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and gre ...

s are known in Europe south to southern England, the

Alps The Alps () ; german: Alpen ; it, Alpi ; rm, Alps ; sl, Alpe . are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately across seven Alpine countries (from west to east): France, Swi ...

, and the

Carpathians The Carpathian Mountains or Carpathians () are a range of mountains forming an arc across Central Europe. Roughly long, it is the third-longest European mountain range after the Urals at and the Scandinavian Mountains at . The range stretches ...

. The species has also been reported from

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

, but this is not accepted by the USDA.USDA Plants Profile
''Salix polaris''
/ref>

References

{{Taxonbar, from=Q39648 polaris Flora of the Arctic Flora of Subarctic America Flora of Northern Europe Flora of the Russian Far East Flora of Siberia Flora of Western Canada Flora without expected TNC conservation status