List of Plants Deadly to Pets

Flowers

• Lilies, commonly found in gardens and bouquets, are particularly deadly to cats. A cat that ingests just a small amount of an Easter lily is at risk for kidney failure and death. In fact, more than 45 percent of the calls to the American Society for the Prevention of Cruelty to Animals (ASPCA) Poison Control Center involve a pet poisoned by lilies. Cyclamens are often sold as small, potted flowering plants that make ideal gifts. The most highly concentrated poisons lurk in the plant's root. If ingested, they can cause gastrointestinal tract irritation, nausea and sometimes death. Bulbs such as tulips, narcissus, autumn crocus and amaryllis are also toxic to pets. The lowly crocus can cause organ failure. The other bulbs may cause cardiac issues, central nervous system depression and convulsions.

Houseplants

• Pothos and schefflera are common houseplants that have dire effects on pets if ingested. According to the ASPCA, pothos causes burning and swelling of the mouth and throat as well as digestive tract irritation. This often results in animals choking and having breathing difficulties. Schefflera, also known as the Australian umbrella tree, produces similar symptoms. Cats or dogs that ingest schefflera may display vomiting, drooling and oral irritation.

Landscape Plants

• Castor beans are sometimes grown for their ornamental foliage. This novelty landscape specimen, however, has earned the dubious title of "the world's most poisonous plant." Two castor beans, which contain the poison ricin, are enough to kill a human. Sago palms, grown in more tropical climates, are also one of the deadliest plants. All parts of a sago palm are poisonous, but the seeds contain the highest toxins. Eating just one or two seeds will be fatal for small animals. Oleanders, azaleas and rhododendrons are all attractive, flowering shrubs that appear to be great additions to any yard. Any of these plants, however, has the potential to kill a pet. Pets that survive may face heart abnormalities and depression of the central nervous system. Yews are also highly poisonous to both humans and pets. Taxine, the poison in a yew, affects the respiratory and nervous systems. It can also cause cardiac arrest resulting in death.

Fruits and Vegetables

• Potatoes are safe for humans but dangerous for dogs. Even the foliage and buds of a potato plant grown in your backyard can cause distress for a small dog. Rhubarb leaves are dangerous for pets, as well. Like the houseplants pothos and schefflera, rhubarb leaves contain oxalates that cause oral swelling, vomiting and diarrhea. The rhubarb stalk is not dangerous, however. Avocados are also poisonous for dogs. According to the ASPCA, avocados can cause vomiting and diarrhea.