Poison Ivy (Toxicodendron radicans): Poison ivy contains urushiol, an oily resin that can cause a severe allergic reaction in most people upon contact, resulting in a painful rash.
Poison Oak (Toxicodendron diversilobum): Like poison ivy, poison oak also contains urushiol and can cause a similar allergic reaction, including a red, itchy rash and blistering.
Poison Sumac (Toxicodendron vernix): Poison sumac, found in wetlands and swampy areas, contains urushiol and can cause a severe rash upon contact with the skin.
Castor Bean (Ricinus communis): The seeds of the castor bean plant contain ricin, a highly toxic protein that can be fatal if ingested in small amounts.
Deadly Nightshade (Atropa belladonna): Deadly nightshade, also known as belladonna, contains tropane alkaloids that can cause hallucinations, paralysis, and even death if ingested.
Oleander (Nerium oleander): Oleander contains cardiac glycosides, which can cause vomiting, dizziness, irregular heartbeat, and even death if ingested in large quantities.
Jimsonweed (Datura stramonium): Jimsonweed contains tropane alkaloids that can cause hallucinations, confusion, dilated pupils, and even death if ingested.
Foxglove (Digitalis purpurea): Foxglove contains cardiac glycosides that can cause irregular heartbeat, nausea, vomiting, and even death if ingested.