Skip to Content Skip to Navigation

Poisonous Plants

Vegetation helps sustain life. We eat many plants, herbs and so forth in our daily diet. But, we must remember to be choosy. Some plants, trees or shrubs are potential killers of man. Some part of the ornamental plants or flowers in your yard may contain deadly poison. Many poisonous plants are so common and seemingly innocuous you do not suspect their toxic qualities. For example, who would expect that the beautiful oleander bush-grown indoors and outdoors all over the country-contains a deadly heart stimulant, similar to the drug digitalis? It is easy to be deceived by plants...one part may be edible while another is poisonous. The following chart lists some of the more common poisonous plants. Treat unknown plants with respect, and teach your children to do the same.

PLANT GENUS TOXIC PART SYMPTOMS
HOUSE PLANTS
Castor Bean Ricinus communis Seeds Fatal. One or two Castor Bean seeds are near the lethal dose for adults.
Daffodil Narcissus Bulbs Nausea, vomiting, diarrhea. May be fatal.
Dieffenbachia Dieffenbachia All parts Intense burning and irritation of the mouth and tongue. Death can occur if base of the tongue swells enough to block the air passage of the throat.
Dumb Cane) Dieffenbachia All parts Intense burning and irritation of the mouth and tongue. Death can occur if base of the tongue swells enough to block the air passage of the throat.
Elephant Ear Colocasia or Alocasia All parts Intense burning and irritation of the mouth and tongue. Death can occur if base of the tongue swells enough to block the air passage of the throat.
Hyacinth Hyacinth Bulbs Nausea, vomiting, diarrhea. May be fatal.
Narcissus Narcissus Bulbs Nausea, vomiting, diarrhea. May be fatal.
Oleander Nerium Leaves, branches Extremely poisonous. Affects the heart, produces severe digestive upset and has caused death.
Rosary Pea, Castor Bean Arbrus precatorius Seeds Fatal. A single Rosary Pea seed has caused death. One or two Castor Bean seeds are near the lethal dose for adults.
Spurge Euphorbia Sap Skin & eye irritation.
FLOWER GARDEN PLANTS
Autumn Crocus Colchicum autumnale Bulbs Vomiting and nervous excitement.
Bleeding Heart Dicentra Foliage, roots May be poisonous in large amounts. Has proved fatal to cattle.
Foxglove Digitalis Leaves Large amounts cause dangerously irregular heartbeat and pulse, usually digestive upset and mental confusion. May be fatal.
Iris Iris Underground stems Severe-but not usually serious-digestive upset.
Larkspur Delphinium Young plant, seeds Digestive upset, nervous excitement, depression. May be fatal.
Lily-of-the-Valley Convallaria majalis Leaves, flowers Irregular heart beat and pulse, usually accompanied by digestive upset and mental confusion.
Monkshood Aconitum Fleshy roots Digestive upset and nervous excitement.
Star of Bethlehem Ornithogalum Bulbs Vomiting and nervous excitement.
VEGETABLE GARDEN PLANTS
Rhubarb Rheum Leaf blade Fatal. Large amounts of raw or cooked leaves can cause convulsions, coma, followed rapidly by death.
ORNAMENTAL PLANTS
Azaleas Rhododendron All parts Fatal. Produces nausea and vomiting, depression, difficult breathing, prostration and coma.
Daphne Daphne mezereum Berries Fatal. A few berries can kill a child.
Golden Chain Laburnum Bean-like capsules in which the seeds are suspended Severe poisoning. Excitement, staggering, convulsions and coma. May be fatal.
Jasmine Jasminum Berries Fatal. Digestive disturbance and nervous symptoms.
Lantana Camara (Red Sage) Lantana Green berries Fatal. Affects lungs, kidneys, heart and nervous system. Grows in the southern U.S. And in moderate climates.
Laurels Laurus All parts Fatal. Produces nausea and vomiting, depression, difficult breathing, prostration and coma.
Rhododendrons Rhododendron All parts Fatal. Produces nausea and vomiting, depression, difficult breathing, prostration and coma.
Wisteria Wisteria Seeds, pods Mild to severe digestive upset. Many children are poisoned by this plant.
Yew Taxus Berries, foliage Fatal. Foliage more toxic than berries. Death is usually sudden without warning symptoms.
TREES AND SHRUBS
Black Locust Robinia Bark, sprouts, foliage Children have suffered nausea, weakness and depression after chewing the bark and seeds.
Elderberry Sambucus All parts, especially roots Children have been poisoned by using pieces of the pithy stems for blowguns. Nausea and digestive upset.
Oaks Quereus Foliage, acorns Affects kidneys gradually. Symptoms appear only after several days or weeks. Takes a large amount for poisoning.
Wild and cultivated cherries Prunus Twigs, foliage Fatal. Contains a compound that releases cyanide when eaten. Gasping, excitement and prostration are common symptoms.
PLANTS IN WOODED AREAS
Jack-in-the-Pulpit Arisaema All parts, especially roots Like Dumb Cane, contains small needle-like crystals of calcium oxalate that cause intense irritation and burning of the mouth and tongue.
Mayapple Podophyllum peltatum Apple, foliage, roots Contains at least 16 active toxic principles, primarily in the roots. Children often eat the apple with no ill effects, but several apples may cause diarrhea.
Mistletoe Phoradendron or Viscum album Berries Fatal. Both children and adults have died from eating the berries.
Moonseed Menispermum Berries Blue, purple color, resembling wild grapes. May be fatal.
PLANTS IN SWAMP OR MOIST AREAS
Water Hemlock Cicuta All parts Fatal. Violent and painful convulsions. A number of people have died from hemlock.
PLANTS IN FIELDS
Buttercups Ranunculus All parts Irritant juices may severely injure the digestive system.
Jimson Weed (Thorn Apple) Datura All parts Abnormal thirst, distorted sight, delirium, incoherence and coma. Common cause of poisoning. Has proved fatal.
Nightshade Atropa belladonna or Solanum All parts, especially the unripened berry Fatal. Intense digestive disturbance and nervous symptoms.
Poison Hemlock Conium All parts Fatal. Resembles a large wild carrot.
Thorn Apple Datura All parts Abnormal thirst, distorted sight, delirium, incoherence and coma. Common cause of poisoning. Has proved fatal.

Chart reprinted from materials provided by the Texas State Department of Health and the National Safety Council.

Back to Top