Status of Goldenseal, Hydrastis canadensis (Ranunculaceae), in Canada

Although found throughout a large area of eastern North America south of th e Great Lakes, the perennial woodland herb, Goldenseal (Hydrastis canadensi s L.), was apparently only abundant in the central portion of its range in Ohio, West Virginia, Indiana, and northern Kentucky. In Canada, it is resti cted to southwestern Ontario where 26 native populations have been reported representing the northern limit of its range. During a 1998 field survey, 21 populations were located, two were not surveyed, and the remaining three could not be found and are assumed extirpated. Attempts to discover additi onal populations with newly acquired ecological data failed suggesting that there are relatively few overlooked populations. Despite recent and rapid increase in the popularity of Goldenseal as an herbal remedy, there appears to have been little if any decline in Ontario populations since it was off icially listed as threatened in 1991. Increasing use of the plant has incre ased the potential threat to Canadian populations and the actual global thr eat has also increased. Goldenseal generally occurs in isolated patches in slightly acid or neutral soil in rich mesic woodlands, often where disturba nces such as tree removal or flooding have occurred. Restriction to isolate d patches may be a consequence of loss of disturbance of the type caused by severe flooding of bottomland forests, fires, and impacts of extinct and e xtirpated fauna. Current research is aimed at understanding the limitations to its spread which may enable populations to be increased and facilitate development of a Canadian agricultural crop thus reducing pressure on natur al populations.