Circumpolar
This group includes broadly distributed plant species that occur on all of the continents in the polar region, including both Asiatic and European regions of Eurasia, Greenland and North America. This group of plants is further divided into arctic/alpine taxa that generally occur in treeless landscapes in the arctic or high alpine regions, and boreal species (those primarily found in lowland and montane habitats). A third element of the circumpolar flora is a group of wide-ranging species with broad ecological amplitudes that occur across both arctic and boreal zones. A fourth category of the circumpolar species are exotic species introduced from other parts of the world into Alaska.
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