- Canadian Poisonous Plants Information System - Plants poisonous to livestock, pets and humans in Canada. Also has links to other poisonous plant resources.
- Cornell University Poisonous Plants - Searchable database of plants toxic to humans and animals.
- Guide to Poisonous and Toxic Plants - From the US Army Center for Health Promotion and Preventive Medicine.
- Guide to Poisonous Plants - Searchable database from the Colorado State College of Veterinary Medicine and Biomedical Sciences.
- Index of Poisionous Plants - Directory of toxic plants and herbs and their effects.
- Poisonous Plant Database - A listing of papers of scientific information about the animal and human toxicology of vascular plants of the world. From the U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition.
- The Poisonous Plant Patch - Detailed information on several species of poisonous plants. Photographs, plant toxins, medicinal or toxic and an illustrated guide to poisonous plants in Nova Scotia. [Many of these are not regional specific - ed]
