poisonous plant

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poisonous plant,

any plant possessing a property injurious to man or animal. Plants may be poisonous to the touch (e.g., poison ivy, poison sumac), or orally toxic (e.g., poison hemlock, deadly amanita). Many poisonous plants are of great value medicinally, e.g., digitalis, belladonna, and aconite. Numerous plants have long been known and gathered (some from prehistoric times) for specific medicinal uses in controlled dosage. Some have been used for hunting poisons (e.g., strychnine) and for insecticides (e.g., pyrethrum). Some plants are poisonous in part and harmless otherwise (the leaf blades, not the stalks, of rhubarb are poisonous) or poisonous at one season and not at another (the very young poke, or pokeweed, shoot is sometimes cultivated as a green vegetable but the older plant is poisonous). Some plants contain properties that are poisonous only under certain conditions, such as those causing photosensitivity. While animals that feed on these plants (buckwheat and others) and are subsequently exposed to sunlight develop a serious skin disorder called photosensitization. A poisonous property (selenium) of some soils, particularly in parts of the West, is absorbed by some of the growing plants, not always in themselves poisonous, and transmitted to animals and sometimes to man. Since this poison is returned to the soil by the death of the plants and animals that have absorbed it, it is again available to other plants and may even be absorbed by crop plants. Locoweed is an example of a selenium-poisonous plant. Many of our ornamental plants are poisonous—larkspur, oleander, English ivy, and lily of the valley. Poisoning by ingestion of plants by human beings is usually a matter of mistaken identity, particularly with mushrooms. Poisonous plants are usually avoided by animals unless the pasture is overgrazed. Poisonous principles may be found throughout the plant kingdom from bacteria and fungi to ferns and flowering plants.


See W. C. Muenscher, Poisonous Plants of the United States (rev. ed. 1951); J. M. Kingsbury, Deadly Harvest: A Guide to Common Poisonous Plants (1965); K. F. Lampe and M. A. McAnn, AMA Handbook of Poisonous and Injurious Plants (1985); W. H. Blackwell, Poisonous and Medicinal Plants (1990).

poisonous plant

[′pȯiz·ən·əs ′plant]
Any of about 400 species of vascular plants containing principles which initiate pathological conditions in man and animals.
References in periodicals archive ?
When pregnant animals graze certain poisonous plants, the consequences can be especially gruesome - an offspring with twisted, deformed legs caused by toxins in lupine, or the bizarre, one-eyed lamb that can result when ewes eat false hellebore, a plant in the lily family.
Sixty two poisonous plant species belonging to 60 genera and 36 families were reported from the area, being utilized by various ethnic groups of the study area.
Plant poisoning and death due to poisonous plant exposure is rare in industrialized parts of the world but continues to be significant cause in India especially in the rural parts.
According to the details, on Wednesday among three girls who ate poisonous plant one died and other two were in critical condition.
Thousands of Australian sheep are becoming "suicidal" after exhibiting drug addiction-like symptoms, apparently triggered by being addicted to a poisonous plant.
Both rumen contents and leaves of the poisonous plant were washed with tap water and then submitted to diaphanisation in a glass beaker, adding 10 ml 5% NaOH solution and heating for about 10 minutes, in order to eliminate the excess of chlorophyll that may interfere with further microscopic observation.
Zheng Tian Wan herbal pills contain aconite, a poisonous plant which can be toxic to the heart and the nervous system and can cause death, said the Medicines and Healthcare products Regulatory Agency.
A strict definition of a poisonous plant is not easily constructed, since the boundaries between harmful and harmless plants are frequently blurred.
IF you think your child has eaten part of a poisonous plant or suffered an allergic reaction to it, don't panic but do seek medical attention from the accident and emergency department of your local hospital, taking a plant sample with you, the RHS advises.
Summary: TEHRAN (FNA)- Researchers revealed that digoxin, the active ingredient in the poisonous plant Foxglove, can enhance the body's own protective mechanism against high blood pressure and heart failure.
The oleander is definitely a poisonous plant, but you see, only the pit (seed) is the poisonous part.
CHARIKAR (PAN): Two girls died after eating a poisonous plant in Bagram district of central Parwan province on Tuesday, officials said.