Status of the Tall Bugbane, Cimicifuga elata (Ranunculacae), in Canada

Abstract

In British Columbia, Cimicifuga elata is restricted to eight recently verified sites in the Chilliwack River valley. Population sizes are relatively small, ranging from a single plant to 63 plants, making this species susceptible to low genetic diversity. Suitable habitat for C. elata in the Chilliwack River valley appears to be mature, mixed Cedar-Hemlock-Maple stands, Douglas-fir-Maple stands, and some deciduous stands. However, most of the range of this species has been extensively converted through logging to young forest. Young stands that develop following harvest do not contain suitable habitat to sustain C. elata, therefore, current forest harvest practises threaten this species. Cimicifuga elata has reproductive limitations that make colonization into new sites difficult. It is relatively much less attractive to pollinators than other flowering plants, and lacks any effective seed dispersal mechanism. Considering these biological limitations, the uncertainty of the effect of logging practices on this species, and the small population sizes, the future of C. e/ata is uncertain in the Chilliwack River valley.