More than 68,000 Americans a year are poisoned by plants. Reactions can range from a skin rash or upset stomach to severe gastrointestinal symptoms or even death. Small children and pets are at highest risk. Common plants that can be harmful: Oleander, datura, castor bean. Ask a garden center or landscaper for more information. Or check this database of poisonous plants from the Week Science Society of America for pictures of these plants… and others.