20 Deadliest Plants on the Planet

Plants provide mankind fresh air, foods, and medicines. Plants also beautify our surrounding with their lovely and colorful flowers. These are just some of the many benefits that plants can give us.

Although many plants are beneficial to human beings there are also certain varieties that have been proven to be harmful and fatal to humans. Here's a list of the deadliest plants in the world. (Photos courtesy of Wikipedia)

1. Oleander (Nerium Oleander)

   
   
   All parts of this attractive bush are toxic especially the leaves and woody stems. Most poisonings have involved ingestions of the leaves. They cause severe digestive upset, heart trouble, and contact dermatitis. It is the deadliest plant in the world. In 2002, there were 847 known human poisonings in the United States related to Oleander and there are innumerable reported suicidal cases of consuming mashed oleander seeds in southern India.

2. Dumbcane (Dieffenbachia)

   
   
   Biting into the leaf causes immediate intense, painful burning in the mouth. This houseplant is one of the most frequently involved in injury to young children. All parts are poisonous, causing intense burning, irritation, and immobility of the tongue, mouth, and throat. Swelling can be severe enough to block breathing leading to death. The Dieffenbachia is considered one of the deadliest plants on earth.

3. Deadly Nightshade (Atropa Belladonna)

   
   
   All parts of this plant contain toxic. The young plants and seeds are especially poisonous, causing nausea, muscle twitches, paralysis; often fatal. Deadly nightshade or belladonna is one of the most toxic plants found in the Western Hemisphere. Children have been poisoned by eating as few as three berries. Ingestion of a leaf of the Belladonna can be fatal to an adult. The root of the plant is generally the most toxic part.

4. Jimson Weed (Datura Stramonium) 

   
   
   This weed is the cause of the first recorded plant poisoning in the United States, in the Jamestown settlement. All parts of Jimson weed which is also known for a variety of names such as datura, thorn apple, stinkweed, and Jamestown weed are poisonous, causing abnormal thirst, vision distortions, delirium, incoherence, coma and often fatal.

5. Angel's Trumpet (Brugmansia) 

   
   
   All parts of the often fatal plant named Angel's trumpet or Brugmansia contain the tropane alkaloids scopolamine and atropine.

6. Monkshood (Aconitum variegatum) 

    

   
   
   All parts of the plant are highly poisonous. Ancient warriors used it to poison their enemies' water supplies. Used in the past for killing wolves. It causes burning, tingling, and numbness in the mouth, then the intestine, followed by vomiting, death by asphyxiation.
   

   Aconitum (Aconitum Napellus)
   
   
   

   The poison is concentrated in the unripe seed pods and roots, but all parts are poisonous. It causes digestive upset, nervous excitement. The juice in plant parts is often fatal. Canadian film actor Andre Noble died of aconitine poisoning in 2004, after accidentally ingesting it. Several species of Aconitum have been used as arrow poisons. The Minaro in Ladakh use A. napellus on their arrows to hunt ibex, while the Ainus in Japan used a species of Aconitum to hunt bear. The Chinese also used Aconitum poisons both for hunting, and for warfare.

7. Yew (Taxus Baccata)
   

   
   
   The seeds are the most poisonous although all parts of the plant, except for the fleshy red bit of the fruit, contain taxane alkaloids. The seeds being especially poisonous are quickly fatal when ingested.

8. White Snakeroot (Ageratina altissima) 

   
   
   All parts are poisonous, causing nausea and vomiting. When consumed by cattle the meat and milk become contaminated. When milk or meat from cattle feeding on White Snakeroot is consumed by humans, the poison is passed onto humans and can result in tremetol poisoning called milk sickness (notably the cause of death of Nancy Hanks, mother of Abraham Lincoln). It is also poisonous to horses, goats, and sheep. Signs of poisoning in animals include depression and lethargy; hind feet placed close together (horses, goats, cattle) or held far apart (sheep), nasal discharge, excessive salivation, arched body posture, and rapid or difficult breathing.

9. Water Hemlock (Cicuta) 

   
   
   The most poisonous part of this plant is the root. The plant is occasionally mistaken for parsnips, due to its clusters of white tuberous roots; this is an often fatal error, as the Cicuta is extremely poisonous. It is considered to be North America's most toxic plant. Cicuta is fatal when swallowed, causing violent and painful convulsions. Though a number of people have died from water hemlock poisoning over the centuries, livestock have long been the worst affected (hence the name “cowbane”), causing death in as little as 15 minutes.

10. Moonseed (Manispermum) 

    
    
    The fruits and seeds of moonseed are poisonous, causing nausea and vomiting and are often fatal.

11. Privet (Ligustrum sp.) 

    
    
    The leaves and berries of privet are poisonous which causes digestive disturbances, nervous symptoms and can be fatal. Privet is one of several plants which are poisonous to horses. In the some parts of the world where they are not native, some privet species have become invasive weeds, spreading into wilderness areas and displacing native species. This is particularly a problem in North America, where no species of the genus occurs naturally. Privet is a huge problem in New Zealand. It is banned from sale or cultivation in New Zealand due to the effects of its pollen on asthma sufferers. Privet pollen is known to cause asthma and eczema in sufferers.

12. Poison Ivy (Toxicodendron radicans) 

    
    
    The smoke of burning poison ivy can cause reactions in the lungs, and can be fatal. All parts of poison-ivy, poison oak, and poison sumac contain highly irritating oil with urushiol (this is actually not a poison, but an allergen). Skin reactions can include blisters and rashes. It spreads readily to clothes and back again, and has a very long life. Infections can follow scratching.

13. Yellow Jasmine (Gelsemium semperivens)

    
    
    Children have been poisoned sucking the nectar from the trumpet shaped flowers. All parts of this plant are poisonous, causing nausea and vomiting. It's possible to become ill from ingesting honey made from jasmine nectar. All parts of this plant contain toxin and should not be consumed. The sap may cause skin irritation in sensitive individuals. The nectar is also toxic to honeybees, and causes brood death when gathered by the bees.

14. Larkspur (Delphinium)

    
    
    Young plants and seeds of larkspur are poisonous, causing nausea, muscle twitches, and paralysis and often fatal. Larkspur is a significant cause of cattle poisoning on rangelands in the western United States

15. Hyacinth (Hyacinthus orientalis)

    
    
    The bulbs of hyacinth are poisonous, causing nausea, vomiting, gasping, convulsions, and possibly death.H. orientalis contains alkaloids and is toxic if eaten in large quantities. The bulb is the most poisonous part and should not be ingested under any circumstances.

16. Hemlock (Conium maculatum) 

    
    
    Ingestion of Poison Hemlock in any quantity can result in respiratory collapse and death. All parts of hemlock contain the relatively simple alkaloid coniine which causes stomach pains, vomiting, progressive paralysis of the central nervous system and can be fatal; it is the poison which killed Socrates and is toxic to people and all classes of livestock. Coniine causes death by blocking the neuromuscular junction.

17. Daphne (Daphne Sp.)

    
    
    The berries of Daphne either red or yellow are poisonous, causing burns to mouth and digestive tract, followed by coma and often fatal.

18. Castor Oil Plant (Ricinus communis)

    
    
    The seeds of a Castor Oil Plant are extremely toxic. It causes burning in mouth and throat, convulsions, and is often fatal. The toxicity of raw castor beans is well-known, and reports of actual poisoning are relatively rare. Children could conceivably die from as few as three beans; adults may require eight or more.

19. Doll's Eyes (Actaea pachypoda)

    
    
    This weird-toy-looking plant is very poisonous. Berries of doll's eyes are highly poisonous, as well as all other parts is considered poisonous to humans. The berries contain cardiogenic toxins which can have an immediate sedative affect on human cardiac muscle tissue, and are the most poisonous part of the plant. Ingestion of the berries can lead to cardiac arrest and death.

20. Foxglove (Digitalis purpurea)

    
    
    The leaves, seeds, and flowers of this lovely-looking plant are poisonous. These cause irregular heartbeat, and generally digestive upset and confusion and can be fatal. The entire plant is poisonous including the roots and seeds. The leaves of the upper stem are particularly potent, with just a nibble being enough to potentially cause death. Early symptoms of ingestion include nausea, vomiting, anorexia, diarrhea, abdominal pain, wild hallucinations, delirium, and severe headache. The plant is toxic to animals including all classes of livestock, as well as cats and dogs.

(Photos courtesy of Wikipedia)

These plants are really beautiful but be careful and watch out for your kids. Refrain from growing ornamental plants that are poisonous.