Panarctic Flora

8646 Hieracium L.

Notes: The predominantly European and western Siberian genus Hieracium (s. str.) is very large in number of named species, about 9000 in total and about 2000 in northwestern Europe alone. A fair number of these reach the Arctic in Iceland, Norway, and European Russia, some in Siberia and Greenland, and a very few in northeastern North America. The vast majority of named species are agamospermous microspecies. The single known sexual exception in the north is H. umbellatum which barely reaches the Arctic.

Following our PAF discussions concerning apomictic groups with very numerous named microspecies, these are generally attempted listed under some kind of aggregates. In Hieracium, two alternative systems have been in use in Europe and Russia the last 50 years. The majority of previous researchers and some recent ones have applied sections or a system of sections, subsections etc. (e.g., Omang and Dahlstedt in Fennoscandia, Iceland, and Greenland; Williams, Kent, and Stace in the British Isles; Sennikov in Russia). The section system is more or less as indicated below, with tentative inclusions of species aggregates: