Top 5 Common But Deadly Plants

5. Oleander (Nerium Oleander)

It may look like an attractive flowering shrub, but don’t be fooled! Oleander is one of the most poisonous of all commonly grown garden plants, and though it’s especially toxic to children it is often planted in school yards. It is a hearty bush and grows on many different continents, and with beautiful, fragrant blossoms, it is tempting to include it in any garden… just don’t even think about touching it or tasting the leaves or stems.
A small child can experience symptoms after handling just one leaf from the plant, though typically it takes more contact for severe reactions to take place. Upon consumption, the poison causes intestinal issues like vomiting, diarrhea (sometimes bloody), excess salivation, and cramping/pain. It can also cause a racing, irregular heart rate, poor circulation, tremors, seizures, coma, and death.

In India, there are many cases of people consuming mashed Oleander seeds to attempt suicide.
4. Manchineel (Hippomane Mancinella)

The flowering plants are considered among the most poisonous trees in the world and are native to Florida, the Bahamas, the Caribbean, Central America and northern South America. The Spanish name is “manzanilla de la muerte: which means “little apple of death.”
In fact, it’s not just the fruit (which does in fact resemble little apples) that is poisonous, but the entire tree is toxic to humans and animals. The tree oozes a white sap when it rains, so standing beneath the tree can cause blistering of the skin. Burning the tree releases extremely toxic fumes which can cause blindness and respiratory problems when humans come into contact with the smoke. Consumption is generally fatal, and it’s, by all accounts, an agonizing death.
It is common for locals to mark the tree with signs or a red X on the trunk to keep people away. The sign on the tree above reads: “Warning! The leaves, bark, and fruits of these trees contain a caustic sap which may be injurious if touched. Columbus described the small green fruits as ‘death apples.’ The trees are common along the Caribbean shores. Avoid contact with any part of this tree!”
3. Deadly Nightshade (Atropa Belladonna)

This plant goes by many names, including Belladonna, Devil’s Berries, and Death Cherries. Both the leaves and the berries are extremely toxic, and children have been known to die from eating just two berries.
One of the most toxic plants in the Western Hemisphere, consumption of Deadly Nightshade leads to delirium, hallucinations, dilated pupils, sensitivity to light, blurred vision, tachycardia, loss of balance, staggering, headache, rash, dry mouth and throat, slurred speech, urinary retention, constipation, confusion, hallucinations, delirium, and convulsions. Without receiving the antidote, sufferers will eventually die due to the plant’s disruption of their body’s involuntary activities such as sweating, breathing, and heart rate.
2. Castor Beans

Castor oil has long been used to aid digestion. While it has a foul taste and consistency, it is not harmful when ingested, yet you may be surprised to learn that just one bean from the plant that is used to make castor oil can be fatal to an adult in minutes.
That’s because when they make castor oil they remove a lethal compound called ricin, making the oil safe to consume. While usually fatal, if consumption of the castor bean (also called a Rosary Pea) doesn’t kill you, you can look forward to symptoms like nausea, emesis, diarrhea, tachycardia, hypotension and seizures, often persisting for up to a week.
1. Water Hemlock (Cicuta)

Water Hemlock grows in temperate regions of the Northern Hemisphere, mainly North America and Europe, usually appearing in marshy areas like wet meadows and along stream banks. Called “the most violently toxic plant in North America,” it is the plant’s roots that contain the deadly sap that, when touched or eaten, causes grand mal seizures and death.
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