There are several plants poisonous to cats and dogs in your garden. Some plants can make animals sick, and some are lethal.
According to Dana Farbman, Senior Manager of Client and Professional Relations within the ASPCA Animal Poison Control Center, the top four plant poisoning calls in 2003 were Cannabis sativa (marijuana), Cycas revoluta (sago palm), Spathiphyllum (peace lily) and Philodendron. “Depending on the plant and exposure situation involved, potential long-term or residual effects from plant poisonings could possibly occur”, she says. “For example, in certain situations, ingestion of cycads (such as Sago Palm) could potentially result in liver failure or residual neurological effects.” Other plants with potential for sickness and toxicity are:
Xanthium strumarium (common Cocklebur)
From the daisy family, this plant has a high toxicity rating for cattle, less so for house pets. Signs include gastrointestinal disorders, cardiac symptoms, behavioral and breathing changes. Care should be taken that the plant isn’t in grazing fields or hasn’t fallen into feed containers. Buying seed and feed from reputable dealers is a better and safer bet.
Hydrangea macrophylla (Hydrangea)
Contains the toxic chemical cyanogenic glycoside. Signs of a poisoning by Hydrangea include loss of weight, high heart rate, fever, vomiting and diarrhea.
Caladium hortulanum (Elephant Ears)
Contains calcium oxalate crystals which clinically produces intense oral irritation and burning. Signs will include excessive drooling, vomiting, increased difficulty in swallowing and general mouth and throat problems.
Euphorbia pulcherrima (Poinsettia)
Once considered a highly toxic plant, the Christmas favorite still has enough bite to sufficiently ruin your pet’s holiday. The sap from the leaves contains an irritant that will make your pet vomit and have head tremors. Take care and leave this one in a safe place in your house.
Coronilla varia (Crown Vetch)
While crown vetch is safe for a number of animals, take care to keep horses from grazing near it. Nitroglycoside, which is broken down in animals such as cows, builds up in horses and can produce symptoms of slow growth, paralysis and sometimes death. A small nibbling shouldn’t hurt, but if your horse digests much, call a vet.
Dicentra ssp. (Bleeding Heart)
Containing the toxin isoquinolone alkaloids, this plant affects cats, cattle and humans. Symptoms will include muscle weakness, staggering and convulsions. Some will see projectile vomiting after ingesting. Rarely animals will die from Bleeding Heart, as treatment is available.
Sambucus canadensis (Elderberry)
Cattle, goats and humans are affected by the toxin sambunigrin. Take care with the leaves, roots and stems, but the berries would take a massively high dose to make you sick.
Oleander: The worst houseplant offender
Known for its ease as a houseplant, oleander is common and beloved. Having white, pink or red showy flowers one to three inches in diameter, this plant can make a shrub or small tree. Easy to grow, and easy on the eyes, oleander is lethal.
Nerium oleander, a member of the dogbane family (Apocynaceae), releases the toxins of oleandrin and nerioside. Similar to the plant foxglove (of which the heart drug Digitalis is made), this plant too affects the heart’s rate and rhythm. Although the sap is bitter like rotten lemons, hungry animals may chew on it. Dry leaves are a bit more palatable to animals, but just as deadly as the green leaves. Don’t let your pet around any part of the oleander plant, whether the whole plant, twigs you remove, or if the plant is burned and smoke is near. A single leaf is enough to kill a small child and 30 to 40 leaves can put horses to death. The signs of poisoning are rapid; usually the animal is just found dead.
If you must have this plant around your yard or house, take care around children and pets. A better, safer bet is just not to have it.