Abstract
Communities of Artemisia sacrorum Ledeb. were surveyed in the Koshin District (a high-snowfall region area outside the indigenous distribution range) and on Hokkaido Island (within the indigenous distribution range) to clarify the adaptations of this species to a snowy environment. Vegetation and growth properties were surveyed in two quadrats (2 m × 2 m) per site in 2014. At all 12 sites in the Koshin District, introduced vegetation developed on roadside cut slopes after ten years and over since road construction, in general shaded by trees. However, at all seven sites in Hokkaido, herbaceous vegetation of A. sacrorum community was found in areas without trees on steep, ocean-facing slopes, involving six sparsely-vegetated grasslands on sea cliffs and one area with introduced vegetation on a reinforced slope. The elongation of creeping stems of A. sacrorum was more marked in the Koshin District. In both regions, winter buds formed on woody stems. The simultaneous production of numerous winter buds was considered advantageous for survival in snowy areas, from the viewpoint of preventing damages caused by stem bending and animals. No significant difference was observed in the average number of seeds per 100 capitula between districts, because of the large variation among sites. Similarly, no significant correlation was observed between the number of capitula and number of seeds per inflorescence. The results suggest that, despite poor growth conditions with a small number of capitula in the Koshin District, A. sacrorum survives by setting fruit occasionally and regenerating naturally.
