Permalink : http://hdl.handle.net/2115/38450

KEYWORDS : Akkeshi;Cochlearia officinalis;Daikoku;Flora

A list of vascular plants (ferns, fern allies and seed plants) of the island of Daikoku, Akkeshi town, eastern Hokkaido has been compiled from seven fieldworks done during 2005-2007. It included 189 plant species with one infraspecific taxon. In contrast to the flora of entire Akkeshi town to which Daikoku belongs administratively, there is notable absence of gymnosperms, Salicaceae, Ericaceae and Orchidaceae on the island. Such absence may be due to the barrier caused by the strait, between the island and the mainland Hokkaido, to the migration of these plants from the mainland and also the scarcity of habitats suitable for them on the island. It has been ascertained that Cochlearia officinalis (Brassicaceae) grows on the sea cliffs at the eastern coast of the island. This "re-discovery" gives new data on the western distribution limit of this boreal and seacliff species within Hokkaido.