Many plants have dangerous components, leaves, seeds and roots. Some of the most dangerous must be grown under government license.
Below are notes on just a few plants to avoid eating.

Mandrake is one of the most poisonous plants that is known. The specimen above is grown under strict control with a fence around it. A member of the nightshade family, Mandrake also contains atropine, scopolamine, apoatropine and hyoscyamine that affect brain functions.

Strychnine, the deadly poison, is produced from the beans of Strychnos ignatii. It is also found in the orange fruit and nuts of Strychnos nux vomica.

Ricin is a poison found naturally in the seeds of the Castor oil plant that also produces the oil that is fed to babies. Ricinus communis ‘Gibsonii’ has red-tinged leaves with reddish veins and pinkish-green seed pods but there are other Castol oil plant varieties.
If castor beans are chewed and swallowed, the released Ricin can cause injury.
Ricin can be made from the waste material left over from processing castor beans into castor oil.

Mescaline is a hallucinogen compound made from the small, spineless cactus Lophophora williamsii or Peyote. It is also present in other cacti including Echinopsis peruviana.
Mescaline is also found in certain members of the Fabaceae bean family.

In ‘Mind-Altering and Poisonous Plants of the World’ by Michael Wink and Ben-Erik van Wyk ‘…. special focus is given to psychoactive plants, which can have stimulant, sedative, hypnotic, narcotic, or hallucinogenic properties. These include cannabis, coca, opium, and scopolamine. “Mind-Altering and Poisonous Plants of the World” is a must for gardeners, farmers, veterinarians, botanists, pharmacists, chemists, doctors, and poison control centers.’ Amazon
It also provides A VIVID REMINDER that ‘Hazardous plants are commonly used as garden ornamentals, potted plants, or florist flowers, yet many people are unaware of the dangers posed by the toxins derived from them.’ Take care with what you eat and protect young children who are often most at risk.

Wicked Plants: The A-Z of Plants That Kill, Maim, Intoxicate and Otherwise Offend by Amy Stewart a poison gardener.

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