Lilies, buttercup and branching ivy are some common plants that are hazardous to cats, according to the American Society for the Prevention of Cruelty to Animals. These plants cause effects on the gastrointestinal tract of cats.
Lily is a common plant, but it is also toxic for cats, as stated by the U.S. Food and Drug Administration. The entire plant is a safety threat for felines, and a small bite of a leaf can cause lethargy, loss of appetite and vomiting. Kidney damage leading to death may also occur. While not all lily species may cause kidney damage, some, such as calla and peace lilies, can irritate the cat's esophagus and mouth.
Buttercup, also known as figwort, usually blooms in spring and grows in all regions of the United States, according to CatHealth.com. The toxic part of the plant is concentrated in the bulbs, and ingestion in large amounts can cause vomiting, unsteady gait, depression and diarrhea.
Branching ivy, or hedera helix, is poisonous to cats, as stated by the ASCPA. The attractive evergreen foliage is more toxic than the berries. Ingestion of the leaves may lead to excessive drooling, abdominal pain, throwing up, coordination issues and widened pupils. The plant is also called English ivy, California ivy and sweetheart ivy. It is also toxic for dogs and horses.