Abstract
Raikoke is a small volcanic island in the Kuril Archipelago for which there has been no previously published botanical research or plant list. Although Tatewaki and Tokunaga collected on the island in 1928, no subsequent botanical investigations were made until the field work performed under the auspices of the International Kuril Island Project (IKIP) in 1996 and 2000. A first plant checklist, including the specimens collected in 1928, is presented here and includes 27 families, 53 genera, and 68 species for the island. Shrubs of Salix subreniformis and S. aquilonia are common on the volcanic ash slope, but Alnus maximowiczii and Sorbus sambucifolia are very rare. Pinus pumila was not found, which is surprising since it is common on other islands in the area. Shrub belts composed of Pinus or Alnus have not formed on the island, indicating that the island remains at an early stage of plant succession after the 1924 volcanic eruption. Establishment of Salix may be easier than that for Alnus or Pinus in the central Kuril Islands because of the more effective long distance seed dispersal in Salix, although the vegetative reproduction of survivors after the volcanic eruption cannot be ruled out. True ferns (Polypodiophyta) appear to be rare on Raikoke.
