Silent But Deadly...


Over time, natural selection has produced plant defense compounds that are used by plants to improve their production by reducing the impact of herbivores. Plants cannot move to escape their predators, so they must have other means of protecting themselves from herbivorous animals. This characteristic of these deadly plants illustrates their adaptation in evolution. Plants use various strategies to defend themselves from the damage caused by herbivores. The production of allelochemicals impacts the behavior, growth, or even the survival of herbivores. The chemical defenses can act as repellents, reducing plant digestibility. Other defensive strategies used by plants include escaping or avoiding herbivores in time or in place, for example by growing in a location where plants are not easily found or accessed by herbivores, or by changing seasonal growth patterns. Another approach diverts herbivores toward eating non-essential parts, or enhances the ability of a plant to recover from the damage caused by herbivory. The study of plant defenses against herbivory is important, not only from an evolutionary view point, but also in the direct impact that these defenses have on agriculture, including human and livestock food sources; as beneficial 'biological control agents' in biological pest control programs; as well as in the search for plants of medical importance.

Five of the Most Silent but Deadly plants:
Doll's eyes (Caroline)
Western water hemlock (Matt)
Manchineel tree (Alexandra)
Angel Trumpet (Sarah)
White Snake Root (Sarah)

The Toxins:
All of the plants mentioned on this page have deadly toxins throughout their bodies. All "Silent but Deadly" plants look like they aren't deadly, but are highly poisonous in every part of their body; their leaves, seeds, fruits, roots, stems, etc. Essential oils, alkaloids, amino acids,cardioactive glycosides, and furanocoumarins are the most important plant substances that cause toxins in plants. Essential oils such as pulegone, which sometime act as scents, can be absorbed by skin and mucous membranes and act as cell poisons. Like essential oils, furanocomarins attack the skin of the plants prey. These acids cause blistering and burning to the skin and sometimes disrupt the way blood clots. Pyridine and Piperidine are two of the most lethal alkaloids, which attack the nervous system of humans and animals. Although amino acids are used to synthesize proteins in the body, there can sometimes be non-protein amino acids that contain toxins, the most toxic being indospicine. Cardioactive glycosides make plants taste bitter and can cause vomiting and in serious causes attack the cardiac system in those who consume the plant. Although there are many different types of toxins, each of these "Silent but Deadly" plants contain some type of poison, causing harm to all that comes in contact with them.
Mentha pulegium, Pennyroyalcontains the deadly oil, Pulegone

Deadly Plants and Murder!:

Some plants such as Monkshood have been used in history for murders. In Europe the plant was used in order to kill mad wolves or dogs. This is how it got its name Wolfsbane or Dogsbane. Even a small dose of this plant can cause severe damage and irritation to the skin and medical treatment may be needed. Being poisoned by this plant causes a burning sensation in the mouth, chronic dizziness, headaches and vomiting. The main use of this plant was for murder and the plant would be imbibed in water and given to the victim. The plant is so toxic and was often used for murder in the Roman empire s the Roman Emperor Trajan banned the cultivation of this plant by penalty of death. An example of a murder case where the toxin aconitine from Monkshood is used is the George Henry Lamson case in 1881 when he murdered his brother-in law Percy John. This plant is the perfect murder weapon because it leaves no trace behind in the bloodstream after the crime. Another use is to kill animals for hunting. The poison from the plant is placed on arrow heads and then shot at animals.

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Monkshood Plant
This plant fits perfectly into the category "Silent but Deadly" because of its beautiful looks and bright purple hues. Although this plant is not commonly found some people have still managed to get their hands on it for murders.

Masters of Disguise:

Lethal plants would not have such a strong effect on the lives of humans and livestock if they were easily discernible. For this reason, plants with deadly poisons often have ways of taking advantage of their environments and traits so that they are not so easily recognized as killer plants. Lethal plants will try to manipulate the senses in order to get creatures to consume them. That means having a showy appearance, giving off a scintillating aroma, or having a sweet taste are all ways that these crafty killers are able to do their dirty work. Pertaining more to humans, some of these lethal plants have names that may lead one to believe they would be safe to consume, such as Angel Trumpet and the Rosary Pea. Also, some poisonous plants have been cited as having a medicinal value, leading people to take their chances and consume the plant. Overall, lethal plants are able to present themselves in ways that allure living organisms.

The Oleander is a highly toxic plant that is used as a decorative shrub. This is an example of using appearance to capture attention.

Prevention and Treatment

Most people would be surprised to find out that some of the attractive plants in their neighborhood are actually very deadly. That is why it is important to become aware of these plants and prevent interaction. Through scientific research and studies, as well as trial and error, some people have discovered which plants are lethal, but there are still many people who have no idea. Before adding plants to your garden, it's very important to research information to prevent health problems for not only yourself but your family and animals. It's also a good idea to have a basic understanding and identification of the plants that are in your neighborhood and any location where you might come across plants. When gardening, wear gloves and keep plants out of reach from children. If exposed to an unfamiliar plant, you should seek medical attention immediately. Do not wait for symptoms to appear! If possible, save a piece of the plant in a container for identification. Deadly plants must be avoided!!!!!


"What Are Toxic Plants -What Makes Plants Poisonous." What Are Toxic Plants -What Makes Plants Poisonous. N.p., n.d. Web. 02 Dec. 2012. <>.

Ecoist. (n.d.). Cute killers: 16 unassuming-but-lethal poison plants. Retrieved from