This "cowbane" is widespread in wetlands on acid soils in eastern states, except New England. Shoots and roots are reportedly toxic to mammals, but there appears to have been little published research on this aspect of the species' biology; the toxin is probably a polyyne similar to that found in Cicita. A much less robust annual relative may also be expected in the state: Cynosciadium digitatum DC. That monotypic genus occurs on hydroxeric base-rich soils of the lower Mississippi Valley and west Gulf Coastal Plain. It is known from s. Ill., se. Mo. and w. Tenn. (K, Y).