Phytolacca americana

[Brian Ellis]

Yes, our soil is very well-draining so that would seem to fit

[TheOnionMan]

In North America where this plant is native, it is an insidious invasive weed that seeds around with wild abandon.  Mature plants grow huge and droop under the weight of large clusters of black-purple berries.  Birds eat the berries & seeds, and all summer long I find seedlings popping up everywhere on my property.  I hate using any chemicals in the garden, but I do use brush-killer to get rid of infestations of this plant and poison ivy, both of which continually re-enter my property from bird droppings.  The plant is impossible to pull once past seedling stage, due to a fat forked carrot-like root, plants must be dug out to get the rhizome.

This plant presents a classic paradox, where the medical world's knowledge of the plant's high toxicity collide with the world of homeopathic & herbal treatments, and folklore.  The curious thing about many of the homeopathic uses of the plant, is that many of the so-called remedies are for conditions that the plant is known to cause. There is also consider scientific interest in this plant because of many unique chemical properties and compounds in the plant.

I have first hand experience of the plant's toxicity for dermatitis, where I got the sap of broken stems on my arms, followed by huge liquid-filled blisters that looked like 3rd degree burns; I had one arm totally wrapped with gauze for 6 weeks, changing the dressing several times a day until it finally healed.


North American distribution. The FNA link has some interesting discussion:
http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220010427
http://plants.usda.gov/java/profile?symbol=PHAM4


Random snippets from various sites discussing the toxicity of Phytolacca americana:

Symptoms of poke poisoning include sweating, burning of the mouth and throat, severe gastritis, vomiting, bloody diarrhea, blurred vision, elevated white-blood-cell counts, unconsciousness, and, rarely, death.

"Poke" is thought to come from "pocan" or "puccoon," probably from the Algonquin term for a plant that contains dye.

The berries of Phytolacca americana, more commonly known as American nightshade and pokeweed, are toxic unless thoroughly cooked by boiling in several changes of water. Severe side effects can occur when people eat them raw, add them to juice or do not cook them properly. People can even become poisoned by phytolacca berries if the substance enters the bloodstream through cuts or scrapes on the skin. Drugs.com notes that people historically used phytolacca berries and other parts of the plant to treat rheumatism and to boost the immune system, but no evidence supports these uses.


Gastrointestinal Effects
Eating uncooked phytolacca berries can cause severe stomach cramps, diarrhea, nausea and vomiting. Prolonged vomiting, vomiting blood and passing bloody diarrhea can occur when the amount of berries consumed reaches toxic levels, according to the Memorial Sloan-Kettering Cancer Center, or MSKCC.

Phytolacca berry toxicity can have many symptoms. As listed by the MSKCC (Memorial Sloan-Kettering Cancer Center), these effects include slow and difficult breathing, low blood pressure, rapid heart rate, weakness, muscle spasms and seizures. The American Cancer Society, or ACS, notes that blurred vision, confusion, dermatitis, dizziness and headaches can occur, as well as heart block, a blockage of the electrical impulses that stimulate heart contractions. Consuming phytolacca berries can be fatal.

Considerations for Women
Pregnant and breastfeeding women should never consume phytolacca berries or other parts of the plant. Phytolacca is a uterine stimulant, according to the ACS, and can cause miscarriage or premature labor. Additionally, toxic components of the berries can have negative effects on a developing baby.

The ingestion of half an ounce of the berries or of the root has proved fatal. In large doses it is a depressant to the spinal cord affecting very markedly the medulla oblongata and causing death by carbonic acid poisoning, the result of
cardiac depression and respiratory paralysis.

E. Preston (1884) calls attention to the peculiar and little-known property of phytolacca leaves to emit, in autumn, a phosphorescent light in the dark.

The berries, though poisonous, lose their toxic qualities somewhat when cooked, and some have gone so far as to make pies of the fruit—a practice which, however, should be condemned. Severe purging has followed the eating of the flesh of pigeons which had fed upon the berries.

According to E. H. Cressler (Amer. Jour. Pharm., 1875, p. 196), the inhalation of the powdered root produces soreness of the throat and chest, severe coughing and inflammation of the eyes.

contain toxins that cause dermatitis

All parts, but primarily the roots, are considered poisonous. Small quantities (more than 10) of raw berries can result in serious poisoning of adults. Fatalities in young children can result from the consumption of a few raw berries.

SYMPTOMS: The more common symptoms are gastrointestinal cramps, vomiting, diarrhea, and convulsions in severe cases. Perspiration, prostration, weakened respiration and pulse, salivation, and visual disturbance are possible symptoms. Death may result. Humans experience an immediate burning sensation in the mouth upon consumption. Postmortem: gross lesions: mild to severe gastroenteritis; congestion of internal organs; histological lesions: stomach ulcerations with hemorrhage.

Cooked, young, tender leaves and stems are eaten by some people as a pot-herb. These young greens are the "poke salad" of Southern fame. They contain low concentrations of phytolacca toxin which is destroyed by proper cooking. Cooked berries are edible and occasionally used in pies, Phytolacca americana contains mitogens, compounds that can be absorbed through skin abrasions, causing blood abnormalities. Sensitive individuals should handle pokeweed with gloves. Root preparations have been used as a folk-medicinal, a practice that can be dangerous.

Applied to the skin, either in the form of juice, strong decoction, or poultice of the root, it produces an erythematous, sometimes pustular, eruption.

Phytolacca slows the heart's action, reduces the force of the pulse, and lessens the respiratory movements. It is a paralyzer of the spinal cord, acting principally on the medulla. In poisoning by this agent tetanic convulsions may ensue. Death results from carbonic acid poisoning, the result of respiratory paralysis. Upon the gastro-intestinal tract doses of from 10 to 30 grains of it act as an emetic and drastic cathartic, producing nausea which comes on slowly, amounting almost to anguish, finally after an hour or so, resulting in emesis. It then continues to act upon the bowels, the purging being prolonged for a considerable length of time.

The plant sap can cause dermatitis in sensitive people. The plant contains substances that cause cell division and can damage chromosomes. These substances can be absorbed through any abrasions in the skin, potentially causing serious blood aberratins, and so it is strongly recommended that the people wear gloves when handling the plant.

[shelagh]

How fascinating Mark, and I always thought it such a wonderfully majestic plant when I have seen it.  The last good stand was in Copenhagen Botanic Garden.

[Diane Clement]

I have grown a Phytolacca sp for several years here and it survives the winter without problems. That is till now - I do not know if it has withstood the frozen soil this winter which has been cold and without snow cover.
I do not think it is americana but a Chinese species grown from Chadwell seeds. It has not selfsowed although it set quantities of berries each fall.   

Hoy, I also have this plant grown from Chadwell seeds, it is Phytolacca acinosa.  I think it is a much better plant than P americana.  I find it quite attractive and although it does seed around a little, it is no trouble to keep under control

[Hoy]

Thanks, Diane! I recognise the berries of your plant and I had the idea that mine could be acinosa as well. Now I am quite sure

[Brian Ellis]

Thanks, Diane! I recognise the berries of your plant and I had the idea that mine could be acinosa as well. Now I am quite sure

Ditto!!  A much more attractive plant, as you say Diane.  Is it the only one that keeps it's berries in that form rather than having them swell into round ones?

[ArnoldT]

Mark:

I know the plant well.  I have it growing around my property.   I must have pulled up five plants last year with bare hands without any toxic effects.  The berries are very staining.  The largest plant must have been almost and inch in diameter.