This publication contains documented evidence on all the native, naturalized, and cultivated plants of Canada that are known to have poisoned humans or animals, or both. Only the most important of those plants which cause dermatitis are mentioned. Also excluded are those plants that cause injuries because of barbs and spines, poisonous blue-green algae, and plant products or plants that produce toxic substances because of the actions of microorganisms. Plants are listed alphabetically by botanical names, with indices to common names and botanical names.