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Tall Bugbane (Actaea elata; formerly Cimicifuga elata) Global: G3 Provincial: S1 COSEWIC: E (May 2001) BC List: Red South Coast Occurrence Range Distribution: Tall bugbane is endemic to the Pacific Northwest, occurring from southwestern British Columbia to southwestern Oregon. In BC it is found only within the Chilliwack River valley at low to mid elevations, below 1600 meters. All 10 known sites occur within the western half of the valley, mostly from Vedder Mountain and Elk Mountain. However, suitable habitat occurs throughout the valley and undiscovered populations likely exist. Naturally rare throughout its range, populations in BC are small and scattered, consisting of only 1 to 63 individuals. Description: This tall perennial reaches up to two meters in height. Plants feature large compound leaves and numerous (50 to 900) tiny white flowers clustered on branched bottlebrush-like racemes. The alternate leaves are divided into threes with 9-17 lobed leaflets, each up to 18 cm long. Like many of its relatives in the Buttercup Family (Ranunculaceae), the flowers of tall bugbane lack petals and instead attract pollinators with numerous showy white stamens. Each flower is surrounded by five tiny sepals. The fruits are dry pod-like follicles (up to 1 cm long) which remain on the plant long after flowering and split open in fall or winter to release about a dozen reddish-brown seeds. However, plants spread primarily by woody horizontal rhizomes rather than by seed. Look’s Like? Young plants may be confused with the more wide-spread baneberry (Actaea rubra), which has similar looking leaves. To tell them apart look at the leaflets. They are broader in tall bugbane (leaflets are wider than they are long) and more egg-shaped in baneberry (leaflets are longer than wide). When mature, these two species are easily distinguished by the flowers and fruits. Flowers of tall bugbane occur in narrow racemes and the fruits are dry follicles. Flowers of baneberry occur in rounded clusters and the fruits are white or red berries. Thimbleberry (Rubus parviflorus) is another species that may be mistaken for tall bugbane when it is not flowering. Thimbleberry has similarly shaped leaves but they are undivided, compared to the leaves of tall bugbane which are divided into groups of three leaflets. Habitat: Tall bugbane occurs in moist, shady, deciduous and mixed forests dominated by Douglas fir, bigleaf maple, western red cedar and western hemlock. It is the deciduous trees in these forests that provide the perfect combination of shade, light and moisture retention. In fact the presence of bigleaf maple (Acer macrophyllum) is the best indicator of suitable habitat for tall bugbane. Tall bugbane is also sometimes associated with red alder (Alnus rubra). Preferring mature or old-growth forests, tall bugbane is absent from young managed forests (less than 30 years old) where there are few canopy openings and increased competition with other plant species. Understory plants commonly associated with tall bugbane include devil’s club, Oregon grape, salmonberry, sword fern, foam flower and vanilla leaf. Tall bugbane is often found near creeks and streams or on seepage slopes and bench lands, where mountain beaver is found. Tall bugbane occasionally colonizes clearcuts and road cuts, although it seems to be unable to persist in these sites. Critical Features Small populations and a sporadic distribution make tall bugbane extremely vulnerable to random events such as drought, intense forest fires, overgrazing by herbivores and natural variations in population growth. At the extreme northern edge of its range, populations in BC are vulnerable to the effects of climate change. The sporadic distribution of tall bugbane is likely due to its low seed germination and dispersal rates, which also limit the ability of this species to recover. The heavy seeds are poorly adapted for dispersal and the flowers are less attractive to pollinators than competing species. To compound this limited ability to colonize new sites, individual plants can persist in a semi-dormant stage with only one or two leaves for several years without flowering at all. Within a site, plants spread primarily by woody rhizomes. Seasonal Life Cycle Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Flowering Fruit production and seed dispersal Threats Forest management and harvesting practices are the main threats to tall bugbane in BC. Harvesting causes habitat loss and fragmentation, threatening existing populations and reducing the amount and quality of mature forest, which is the preferred habitat of this species. With its limited ability to produce viable seeds, this species is further threatened by adverse impacts to its pollinators, mainly bumblebees and honey bees. Bees are vulnerable to pesticide use, the spread of infectious diseases and the destruction of their nests during logging activities. Tall bugbane is sold in nurseries as a garden plant and is also used for medicinal purposes. Because populations consist of so few individuals and tall bugbane is such a poor disperser, this species is especially vulnerable to over-harvesting. Conservation Objectives Protection is needed for all known populations in BC, especially since nearly all occur on unprotected land. Historical and potential new habitat should be identified and maintained as recovery habitat. The health of existing populations must be protected to encourage population growth and dispersal. Research is underway to uncover information that will help us to conserve and recover tall bugbane in BC. Knowing more about tall bugbane’s population dynamics, life history characteristics, relationships with pollinators and specific habitat requirements will help us determine how to achieve that goal. In BC all tall bugbane populations occur within managed forests. It is important to compare the effects of different forest harvesting practices on the long term viability of this species in managed forests. Management Practices Check List Protect populations by creating a core area, with a buffer and surrounding management zone. The core area should enclose the perimeter of the population and be surrounded by a 30 to 50 meter buffer. The surrounding management zone should be between 150 and 200 meters or wider, depending on the site. Maintain a diverse stand structure, retain canopy gaps and encourage deciduous trees and shrubs, especially bigleaf maple, where populations occur. Maintain site hydrology and microclimatic conditions within the core area. Minimize human impacts and disturbance to populations. Prevent forest harvesting and salvaging within core areas. Minimize the construction of roads, trails, recreational facilities and stream crossings within the management zone. Within the management zone, minimize damage to plants during road maintenance activities, such as grading and brush cutting. Prevent mowing and spraying of plants. Do not use pesticides or herbicides near populations. Avoid broadcast spraying within forest stands where tall bugbane resides. Prevent the introduction and spread of invasive plants which will easily outcompete this poor competitor. If seeding is required to restore sites near tall bugbane populations, use only native species. Prevent harvesting of plants and seeds by collectors. Enclosures can be used around populations to reduce grazing and increase seed production. Mitigating Impacts Within populations encourage canopy gaps to promote more vigorous growth and flowering. Continue to distribute information like the BC Provincial Government’s “Tall Bugbane, Endangered” brochure to encourage the public to report new populations and reduce unnecessary harvesting. Main References/Literature Cited B.C. Ministry of Water, Land and Air Protection. 2004. Tall Bugbane (Cimicifuga elata) in Accounts and Measures for Managing Identified Wildlife – Accounts V. 2004. [http://www.env.gov.bc.ca/wld/frpa/iwms/accounts.htm] B.C. Ministry of Water, Land and Air Protection, Victoria, B.C. Accessed June 2008. British Columbia Conservation Data Centre. 2008. BC Species and Ecosystems Explorer [http://a100.gov.bc.ca/pub/eswp/]. B.C. Ministry of Environment, Victoria, B.C. Accessed June, 2008. Douglas, G.W., D.V. Meidinger, and J. Pojar (editors). 1999. Illustrated Flora of British Columbia. Volume 4: Dicotyledons (Orobanchaceae Through Rubiaceae). B.C. Ministry of Environment, Lands & Parks and B.C. Ministry of Forests. Victoria. 427 p. Klinkenberg, Brian. (Editor) 2006. E-Flora BC: Electronic Atlas of the Plants of British Columbia [www.eflora.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. Klinkenberg, Brian. 2007. National Recovery Strategy for Tall Bugbane, Actaea elata, in Canada. South Coast Conservation Program and BC Ministry of Environment. Klinkenberg, Brian and Rose Klinkenberg. 2003. National Recovery Strategy for Tall Bugbane (Actaea elata) in Canada. Recovery of Nationally Endangered Wildlife (RENEW). Ottawa, Ontario. Draft. Knopp, D. and L. Larkin. 2005. National Recovery Action Plan for Tall Bugbane (Actaea elata) in British Columbia, Five Year Plan - 2003 to 2008. Recovery of Nationally Endangered Wildlife (RENEW). Ottawa, Ontario. Draft. NatureServe. 2008. NatureServe Explorer: An online encyclopedia of life [http://www.natureserve.org/explorer/]. Version 7.0. NatureServe, Arlington, Virginia. Accessed June, 2008. Penny, Jenifer L. and George W. Douglas. 2001. COSEWIC Status Report on the Tall Bugbane (Cimicifuga elata) in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. SARA Public Registry Office. 2007. Species at Risk Public Registry [http://www.sararegistry.gc.ca]. Environment Canada, Government of Canada, Ottawa, Ontario. Accessed June, 2008. Image credits: all photographs by Brian Klinkenberg. NOTE: There is an error in the Tall Bugbane brochure on the SCCP website under the “Habitat” section. The sentence “Three of the shrubs that occur most frequently near Tall Bugbane include Devil’s Club (Oplopanax horridum), Oregon grape (Mahonia nervosa) and salmonberry (Rubus parviflorus)” should read “…Oregon grape (Mahonia nervosa) and salmonberry (Rubus spectabilis)”.