Plants Toxic to Pets


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As the spring weather warms up and plants start to emerge, or you plan your plant purchases, it is a good time to be aware of any potential poisons, which may be lurking in your gardens. A variety of plants may be toxic to cats and dogs. Both indoor and outdoor plants can cause a threat to our four-legged friends. Be careful not to confuse noxious with toxic. Toxic means poisonous. Some plants may contain oxalates, which can be toxic. The definition of noxious is a weed classified under the Iowa Weed Law. The law gives each county the authority to order the destruction of weeds classified as noxious by the state. Also be careful of plants with similar appearances and look-a-likes such as ground ivy which may be confused with henbit, but neither of these are considered toxic. As you plan your garden and plants for the growing season, be mindful to keep an eye on your four-legged friends to keep them safe from encountering plants which may be toxic.

According to the American Society for the Prevention of Cruelty to Animals (ASPCA) website, the number of phone calls to the Animal Poison Control Center (APCC) increased from 2019 to 2020 due to bouquets and plants. Check out their list at for a complete list, which includes links for cats, dogs, and horses. The list is lengthy but may not be comprehensive. Consumption of some plant material may cause vomiting and gastrointestinal upset for dogs and cats. Some plants may cause an oral irritation, pain and swelling of the mouth, tongue and lips, excessive drooling or difficulty swallowing. Some plants may be lethal. Some plants can cause tremors and seizures, and ingestion can cause in coordination or may cause liver damage. In horses, some plants may cause colic. If you believe that your animal is ill or may have ingested a poisonous substance, contact your veterinarian or the ASPCA APCC 24-hour emergency poison hotline (888) 426-4435.

In the Iowa State University Weed Identification Field Guide, weeds are identified which are considered both noxious and/or toxic. Weeds may be annuals, biennials or perennials. Weeds are generally arranged into three categories: grass, broadleaf and other weeds. Weeds are broken down into their various families. Noxious weeds in Iowa include quack grass, poison hemlock, common cocklebur, field bindweed, and horse nettle.

Toxic weeds include the following:

The Apiaceae or Umbelliferae is a family of mostly aromatic flowering plants named after the type genus Apium and commonly known as the celery, carrot or parsley family, or simply as umbellifers. The following toxic plants are in the Apiaceae family.

  • Poison hemlock (Conium maculatum, also known as Deadly hemlock, poison parsley). As the name suggests, all plants are poisonous to humans and livestock. The foliage has a strong parsnip odor.
  • Wild Parsnip (Pastinaca sativa)has become well known in recent years. If plant sap gets on skin that is exposed to sunlight, the skin may redden and develop a rash. Blisters and burning pain may occur in severe cases.

The family Asteraceae, alternatively Compositae, consists of a very large group of flowering plants. Compositae commonly refers to the aster, daisy, composite, or sunflower family. The following is in the Asteraceae family:

  • Common Cocklebur (Xanthium strumarium) seedlings and seeds can be toxic if ingested.

The Convolvulaceae family, known commonly as the bindweed or morning glory family, is a family of mostly herbaceous vines, but also trees, shrubs and herbs, and also includes the sweet potato and a few other food tubers. The Convolvulacaea family includes:

  • Field bindweed (Canvolvulus arvensis, also known as Creeping Jenny, field morning glory). These plants may become toxic to livestock.

The Phytolaccaceae is a family of flowering plants. It is also known as the Pokeweed family. All parts of the mature Common Pokeweed (Phytolacca americana, inkberry, pokeberry) plant are poisonous, especially the roots, The dark red berry juice easily stains.

The Solanaceae, or nightshades, are a family of flowering plants that ranges from annual and perennial herbs to vines, lianas, epiphytes, shrubs, and trees, and includes a number of agricultural crops, medicinal plants, spices, weeds, and ornamentals. Many members of the family contain potent alkaloids, and some are highly toxic, but many—including tomatoes, potatoes, eggplant, bell and chili peppers—are used as food. The following are in the Solanaceae or nightshade family:

  • Jimsonweed (Datura stramonium, moonflower, thornapple). Crushed leaves and stems produce a distinctive unpleasant odor. All plant parts are poisonous.
  • Smooth Groundcherry, longleaf groundcherry (Physalis longifolia). The leaves and unripe fruit are poisonous.
  • Horsenettle (Salarnum carolinense, bull nettle). The leaves smell like a potato when crushed. Leaves, stems, and berries are poisonous, even when the plant is dead.
  • Eastern black nightshade (Solanum ptycanthum, black nightshade) All plant parts are poisonous. Plant parts become more toxic with age, except for the berries. Berries mixed with harvested soybeans can stain beans and reduce the value of the crop.
  • Buffalobur (Solanum rostratum, Kansas thistle, prickly nightshade). The leaves, berries and roots are poisonous. The spines can cause injury.

Houseplants which are toxic to cats and dogs include the following:

The Araliaceae is a family of flowering plants composed of primarily woody plants and some herbaceous plants. It is predominantly distinguishable based on its woody habit, tropical distribution, and the presence of simple umbels. Australian Ivy Palm (Brassaia actinophylla) (Schefflera, Umbrella Tree, Octopus Tree, Starleaf) is included in the Araliaceae family.

The Araceae are a family of monocotyledonous flowering plants in which flowers are borne on a type of inflorescence called a spadix. The spadix is usually accompanied by, and sometimes partially enclosed in, aspathe or leaf-like bract. Also known as the arum family, members are often known as aroids. Devils Ivy (Epipremnum aureum, Pothos, Golden Pothos, Taro Vine, Ivy Arum) and Dieffenbachia (Dieffenbachia, Charming Dieffenbachia, Giant Dumb Cane, Tropic Snow, Dumbcane, Exotica, Spotted Dumb Cane, Exotica Perfection) are included in this family.

The Crassulaceae, also known as the stonecrop family or the orpine family, are a diverse family of dicotyledon flowering plants characterized by succulent leaves. Flowers generally have five floral parts. The Crassulaceae family includes Devil’s Backbone (Kalanchoe tubiflora, Mother-In-Law-Plant, Kalanchoe, Chandelier Plant, Mother of Millions).

Crassula ovata, commonly known as Jade Plant (Crassula, Baby Jade, Dwarf rubber plant, Jade tree, Chinese rubber plant, Japanese rubber plant, lucky plant, money plant or money tree) is a succulent plant. The jade plant is very toxic to dogs, causing gastric distress, heartbeat irregularities, and depression among other symptoms. When cats or dogs ingest this houseplant, they may vomit, become uncoordinated or have loss of muscle function, lethargy, slow heart rate, or depression. Your cat may be more aggressive, fail to groom itself as usual, or hide more.

Lilies, which may be found in a bouquet, are toxic to cats. Lilies in the “true lily” and “daylily” families are very dangerous for cats. The entire lily plant is toxic: the stem, leaves, flowers, pollen, and even the water in a vase. Eating just a small amount of a leaf or flower petal, licking a few pollen grains off its fur while grooming, or drinking the water from the vase can cause a cat to develop fatal kidney failure in a very short period of time. Dogs that eat lilies may have minor stomach upset but they don’t develop kidney failure.

Interestingly, not all parts of a Poinsettia are poisonous. The poinsettia is a commercially important plant species of the diverse spurge family. Though often assumed to be highly toxic, the poinsettia is not dangerous to pets or children. Exposure to the plant, even consumption may cause nausea, vomiting, or diarrhea.

So as you are in your yard with your furry four-legged friend, please remember to be aware of anything they may be interested in nibbling, and any potential hazards they may be subjecting themselves to.


  1. Iowa State University Extension and Outreach Weed Identification Field Guide 2nd Edition (copyright 2015)
  2. American Society for the Prevention of Cruelty to Animals