Household plants reflect a decorator's tastes and gardening prowess, and add to the look and feel of your home. They take in carbon dioxide and release oxygen, improving air quality, and through transpiration, infuse dry air with needed humidity. However, many beautiful plants -- including some species of fern -- are highly toxic to pets, and can cause serious illness and even death.

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Many ferns are indeed poisonus to pets, but not the popular Boston fern.

Boston Fern Not Poisonous

Boston ferns make great indoor houseplants. Perennials often set in hanging baskets, they add color and texture to a room and can be a bold addition to a decorating theme. Although easy to care for, they do demand high humidity and do best with continuously moist soil, indirect sunlight and regular misting. Unlike some ferns, the Boston fern is not poisonous to pets, but can be attractive to some animals, especially cats.

Cats and Plants

The wispy fronds of the Boston fern are often enticing toys to cats and kittens. If you find your plant damaged and your cat spitting up fern leaves, it likely only means that left on his own, your cat has eaten too much of a harmless plant. Discourage the behavior by spraying the foliage with Bitter Apple or a solution of vinegar and water. If you catch your cat in the act, startle him with a firm "no." Also give him plenty of alternative toys and interactive playtime, so he's less interested in your houseplants.

Poisonous Ferns

There are many ferns that are poisonous to animals. Some, like the asparagus fern, are called by a variety of names. To create a pet-friendly environment, avoid ferns including the Australian nut, emerald feather, lace, Plumosa, Racermose, Shatavari and Sprengeri.

Other Poisonous Plants

Some other common poisonous houseplants are Alocasia, Anthurium, Azalea, cardboard palm, Caladium, Chinese evergreen, Christmas holly, Cordatum, cornstalk plant, devil's ivy, Dracaena, dumb cane, English ivy, marble queen, Nephthysis, Peace Lily, Philodendron, Pothos and the Taro vine.

What to Do

Signs that your pet may have ingested a toxic plant include pain, diarrhea, and vomiting. Contact your vet immediately if you suspect poisoning, or call the ASPCA poison hotline at 888-426-4435.