Effects of timber harvest on Cimicifuga elata, a rare plant of western forests

Cimicifuga elata (tall bugbane) is a Species of Concern with the U.S. Fish and Wildlife Service and it is considered by Natural Heritage programs in O regon and Washington to be endangered. Since the species occurs in forests, its conservation could conflict with other forest uses such as timber han est. It has been postulated that the species is dependent on old-growth con iferous forests. The objectives of this study were to compare populations o f this species among sires with differing forest-management histories. In c ontrast to previous reports, we found that C. elata in uncut old-growth for est was smaller and less reproductive than in clearcuts, probably because p lants responded well to additional light in cut-over areas. Plants in areas with other management histories. such as second growth and thinned stands (both >70 years old), were intermediate in size. Population structure also differed among management types. Herbivory by deer and elk was more frequen t in clear cuts and edges than in unmanaged old-growth forests. No populati ons were known at the time of this study from second growth forests of mode rate age (20-30 years), and it is possible that competing vegetation exclud es C. elata from clearcuts after a few years. Management actions that retai n hardwoods. thin stands, or create gaps may improve at least short-term co nditions for this species.