Characteristic features, ecology and natural history:
2) North American or European?
The question of whether Iceland's flora is primarily American or European can easily be answered: it is predominantly European. As mentioned on the introduction page of this section, only about 10 species are regarded as truly American, whereas approximately 100 species are considered truly European. Nevertheless, several American species play an important role in Iceland's vegetation. One example is the Lyngbye's Sedge (Carex lyngbyei - Gulstör) Lyngbye's Sedge (Carex lyngbyei - Gulstör) which is a dominant species in Icelandic wetlands. It is a large sedge that can easily be distinguished from Iceland's only other tall sedge, the Bottle Sedge (Carex rostrata), by its characteristic drooping spikes.
Closely related to this sedge is the Hoppner's Sedge (Carex subspathacea - Flæðastör) Hoppner's Sedge (Carex subspathacea - Flæðastör) . This sedge is a very small species that grows on salt soils all along the coast The Lyngbye's and Hoppner 's sedges are believed to be closely related (although the don't resemble each other at all). The Hoppners's sedge is found not only in Iceland and North America but also in northern regions of Scandinavia, Russia and Eastern Asia.
A more puzzling species is the Ramenski's sedge (Carex ramenskii). Ramenski's sedge (Carex ramenskii). This is a predominantly Northern American species that is generally regarded to be a stable hybrid of the two just mentioned sedges. However, it is not certain that the Icelandic populations really belong to this species. If it proves to be an entirely different species it should be regarded as an endemic species. But this is a speculative thought. For more information see: "Carex Europaea (3rd ed)" by Jacob Koopman (Margraf Publishers ISBN: 978-3-8236-1791-4) - page 467). If the Icelandic populations are of a dirrerent species all together it could be regarded as an endemic. However, most botanists recognizes them as "ramanskii". For more information see panarcticflora.org/taxon/3309071. It grows on grassy brackish soils, especially in fjords where freshwater rivers meet the sea. Its habitat is only rarely flooded by seawater.
Another species with a predominantly American distribution is the Arctic River Beauty (Chamerion latifolium - Eyrarrós) Arctic River Beauty (Chamerion latifolium - Eyrarrós) . Although this species occurs locally in parts of Eurasia, its main distribution is in North America (especially Alaska and Canada), Greenland, and Iceland.
Continue with:
1) introduction
2) Is the flora North American or European? (this page)
3) The main vegetation types
4) Regional differences in the flora
5) The influence of the glacial periods and the revegetation following the last glacial period