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.