Poisonous plants in New ZealandSome of the poisonous plants found in New Zealand.
New Zealand is home to many native and introduced poisonous plants. These plants vary in degrees of toxicity.
It is important to treat unknown plants with caution and teach children to do the same.
Plants that are attractive in appearance increases the likelihood of being eaten by children.
The National Poisons Centre in Dunedin (www.poisons.co.nz) receives many calls each year from doctors and members of the public after children and animals have eaten berries, flowers, leaves, and fungi.
Top safety tips for minimising harm from poisonous plants:
Be aware of which of plants in New Zealand are poisonous, and know the plants and trees in your house and garden. Remove poisonous plants or move them to a part of the garden or house that children can’t reach.
Teach children not to eat or gather any berries or plant matter unless guided by an adult who knows that the plant is safe for human consumption.
Check the label when you buy a plant, or ask staff at the Garden Centre to check if the plant is poisonous.
Clear away berries, flowers and leaves from poisonous plants that fall onto lawns and paths.
Don’t eat fungi unless you are an expert. Fungi can be very hard to identify. If you have young children, check your lawn and garden regularly, and remove all fungi safely.
Pre-schools or primary schools need to know which plants to avoid on their grounds, and be able to identify them. Plants listed below should not be grown or tolerated in pre-school centres.
There are over a hundred poisonous plants in New Zealand, and many people don’t know which plants are poisonous. Most are introduced species, and many are only present in gardens.
Warning: If the child is displaying serious symptoms of poisoning, treat as an emergency and dial 111 for an ambulance.
If you suspect a child has ingested parts of a poisonous plant, immediately contact the National Poisons Information Centre Urgent 24 Hour Phone line on 0800 POISON (0800-764766). You can also call your doctor.
For non-urgent information, call 03 479 7227. Their web site is http://www.poisons.co.nz.
Important Disclaimer of Liability for Health-Related Advice. We accept no liability whatsoever by reason, non-inclusion of a plant, negligence or otherwise arising from the use or release of this information or any part of it. This information is not intended to be comprehensive or to provide medical advice to you. Specific advice on medical issues should be sought from a health professional.
Listed below are some of the common plant species in New Zealand associated with poisonings.
Arum (Zantedeschia species).
Zantedeschia shares the general properties of the Araceae family in causing contact irritation. Zantedeschia species are also poisonous due to the presence of calcium oxalate crystals in the form of raphides. All parts of the plant are poisonous, typically producing local irritation or a burning sensation in the mouth and occasionally vomiting and diarrhea. However leaves are sometimes cooked and eaten.
A video on an arum species:
For more details of Zantedeschia visit:
Agapanthus (Agapanthus species)
All parts of the plant are poisonous, especially the rhizome.
The poisonous principles in Agapanthus are yuccagenin, a haemolytic saponin and a steroidal saponin called agapanthogenin.
The leaves contain a sticky irritant sap, the rhizomes, however, are very toxic.
The sticky sap can cause severe ulceration in the mouth, and irritation to the skin and eyes.
Ingestion of any part of this plant causes immediate intense pain, local irritation to mucous membranes, excess salivation, swollen tongue and pharynx, diarrhoea, and dyspnea (breathlessness).
For more detail on Agapanthus visit:
Apple of Peru (Nicandra physaloides).
Nicandra physaloides belongs to a family that contains many species of poisonous plants so some caution is advised. It is normally the leaves and the unripe fruits that are most likely to be suspect.
For more details of Nicandra physaloides visit:
Apple of Sodum (Solanaum sodomeum).
The green fruit is especially toxic to children and sheep due to a toxin glycoalkaloid solasonine.
If ingested the symptoms are abdominal pains, nausea, vomiting, diarrhoea, dizziness, dryness of the mouth and diluted pupils.
Apricot (Prunus armeniaca)
The poison parts if ingested are wilted leaves, twigs (stems), seeds; laetrile from the seeds. They are toxic due to cyanogenic glycosides and amygdalin.
Symptoms are gasping, weakness, excitement, pupil dilation, spasms, convulsions, coma, respiratory failure.
Angel's trumpet (Brugmansia candida)
All parts of Brugmansia are extremely toxic, with the roots, stems, flowers, leaves and seeds being especially dangerous. Brugmansia are rich in scopolamine (hyoscine), hyoscyamine, and several other tropane alkaloids.
Effects of ingestion can include paralysis of smooth muscles, confusion, tachycardia, dry mouth, diarrhoea, migraine headaches, visual and auditory hallucinations, mydriasis, rapid onset cycloplegia, and death.
Found mainly in the North Island and warmest parts of South Island
For more details of Brugmansia candida visit:
Anthurium (Flamingo flower)
Anthuriums have dark, glossy, heart-shaped leaves with glossy, heart-shaped flowers which can be red, white or other colours. The plant contains calcium oxalate crystals which an cause severe mouth pain if eaten. Large amounts would need to be eaten to cause poisoning. If the plant’s stem is broken, milky sap will ooze out. This sap contains the toxin calcium oxalate. When these crystals come in contact with your skin it will cause severe itching, dermatitis, skin irritation (burning and red skin) and eye irritation.
The sap also contains proteolytic enzymes which can cause fatal reactions to some people.
Ingestion is rare because of the bad taste of calcium oxalate but if ingested the localised symptoms include blistering, dysphagia (hard to sallow) and hoarseness.
Asparagus (Asparagus officinalis).
The poison part is the small bright red berries. The unharvested plants will grow and produce during summer small red berries up to 10 mm in diameter. These are mildly poisonous, causing abdominal pain and vomiting after ingestion.
A contact dermatitis consisting of a rash in the area of contact is possible from handling young, raw shoots.
The toxic element is thought to be caused by the sulfur-containing growth inhibitor 1,2,3-Trithiane-5-carboxylic acid, according to the New Zealand Dermatological Society.
Asparagus fern (Asparagus densiflorus)
The poisonous part are the berries which cause the same intestinal reaction as those from the edible asparagus plant.
The sap will produced a low-level rash, usually only lasting a few minutes. Asparagus fern is toxic to cats and dogs, causing skin irritation with exposure to the sap.
Bitter Almond (Prunus dulcis var. amara)
Prunus dulcis var. amara is not to be confused with the edible sweet almond (Prunus dulcis var. dulcis) which does not contain poisonous chemicals. Prunus dulcis has pink flowers, as opposed to Prunus dulcis var. amara having white flowers with a pink base.
Bitter almond kernels are poisonous due to cyanogenic glycosides and amygdalin. When eaten the glycoside amygdalin will turn into prussic acid, (hydrogen cyanide).
Symptoms are gasping, weakness, excitement, pupil dilation, spasms, convulsions, coma, respiratory failure. It is thought that the ingestion of about 20 bitter almonds are enough to kill an adult.
Bittersweet (Solanum dulcamara)
The shining scarlet berries and all parts of the plant are highly toxic due top Solanine and other alkaloids.
Symptoms are nausea, vomiting, salivation, drowsiness, abdominal pain, diarrhoea, weakness, respiratory depression; may be fatal.
Found mainly in the South Island and lower North Island
A video on Solanum dulcamara:
For more details of Solanum dulcamara visit:
Black Nightshade (Solanum nigrum and similar species)
Not to be confused with Deadly Nightshade, which as white star-like flowers this plant has quite large bell-shaped brownish-purple flowers.
This plant is poisonous. Though some literature suggests that ripe berries are not poisonous, the toxicity of Solanum nigrum varies widely depending on the variety, and poisonous plant experts advise to avoid eating the berries unless they are a known edible strain. The toxins glycoalkaloids including solamargine, solasonine and solanine are most concentrated in the unripe green berries, but can also occur in ripe berries.
Poisoning symptoms are typically delayed for 6 to 12 hours after ingestion. The initial symptoms of toxicity include fever, sweating, vomiting, abdominal pain, diarrhoea, confusion, and drowsiness. Death from ingesting plant parts results from cardiac arrhythmias and respiratory failure.
Box (Buxus semoervirens)
The plant contains the alkaloid buxine which causes nausea, vomiting and diarrhoea. The leaves are poisonous to humans but its unpleasant odour and bitter taste tends to minimise its ingestion. Farm stock, especially cattle are said to have grazed box bushes if they get into gardens. Death may occur through respiratory failure.
Contact can cause skin rashes and the clippings should be handled with care.
Boxthorn (Lycium ferocissimum)
Berries, leaves, stems and roots contain alkaloids that are toxic to humans and livestock producing a narcotic effect. The spines are mildly poisonous. The symptoms are nausea,vomiting, slowing of the heart action,reduction in muscle power, difficult in breathing and unconsiousness.
For more details of Lycium ferocissimum visit:
Broom (Cytisus scoparius).
Broom is a pest plant found along roadsides and in paddocks and all parts are toxic.
Quinolizidine alkaloids are the toxic principles which depress the heart and nervous system.
If ingested the symptoms are vomiting, excitement, muscular weakness and convulsions.
For more dcetails on Cytisus scoparius visit:
Bushman's poison (Acokanthera oppositifolia & relative species)
All parts of this tree are highly toxic due to the deadly cardiotoxic glycoside ouabin.
The milky sap of this plant was widely used by the traditional bushmen (Khoisan) to form part of the cocktail used to poison the tips of their notoriously toxic arrows in hunting.
All plants of the genus Acokanthera contain toxic cardiac glycosides strong enough to cause death.
Buttercups (Ranunculis several species)
All Ranunculus species are poisonous when eaten fresh by cattle, horses, and other livestock, but their acrid taste and the blistering of the mouth caused by their poison means they are usually left uneaten. Poisoning can occur where buttercups are abundant in overgrazed fields where little other edible plant growth is left, and the animals eat them out of desperation.
When children play with ranunculus plants and their bright yellow flowers a naturally occurring ranunculin is broken down to form protoanemonin, which is known to cause contact dermatitis in humans. Hence care should therefore be exercised in extensive handling of these plants.
Symptoms of ingestion include bloody diarrhoea, excessive salivation, colic, and severe blistering of the mucous membranes and gastrointestinal tract. The toxins are degraded by drying, so hay containing dried buttercups is safe.
Calico bush (Kalmia latifolia)
This plant is highly toxic to humans and other animals The green parts of the plant, flowers, twigs, and pollen are all toxic, including food products made from them, such as toxic honey that may produce neurotoxic and gastrointestinal symptoms in humans eating more than a modest amount.
The toxic principles are a resinoid called andromedotoxinand a glycoside called arbutin.
Symptoms of toxicity begin to appear about 6 hours following ingestion. They include irregular or difficulty breathing, anorexia, repeated swallowing, profuse salivation, watering of the eyes and nose, cardiac distress, in-coordination, depression, vomiting, frequent defecation, weakness, convulsions, paralysis, coma, and eventually death. Autopsy will show gastrointestinal irritation and haemorrhage.
Cape honey flower (Melianthus major)
Melianthus major is very poisonous and have caused death in people and animals. The entire plant is toxic, especially the roots. The plant contains toxic bufadienolides (cardiac glycosides). Ingestion by humans and animals can produce symptoms of increased salivation, vomiting, bloody diarrhea, cyanosis of the mucous membranes, rapid weak pulse, and extreme exhaustion. Dead animals show haemorrhage and oedema of the lungs, pericardial haemorrhage, general cyanosis and congestion of the liver and kidney. Livestock rarely ingest the plant because of the unpleasant smell, but may be forced to during drought and scarcity of grazing.
The dark honey produced from the characteristic black nectar may be toxic. New Zealand’s nectar feeding birds like the silvereye, bellbird, and tui may be affected.
For more information on this plant visit: http://www.terrain.net.nz/friends-of-te-henui-group/weeds-by-scientific-names/melianthus-major-cape-honey-flower.html
Cape Tulip (Homeria collina)
All parts are extremely poisonous to both livestock and humans even when dead and dry due to cardiac glycosides. Deaths have been recorded in Africa when people have mistaken the bulbs for edible tulp(Moraea fugaxor M. edulis).
Symptoms are acute vomiting, diarrhoea, depression and weakness.
Caper spurge (Euphorbia lathyris)
Caper spurge (Euphorbia lathyris) is poisonous to humans and most livestock. All parts of the plant, including the seeds and roots are poisonous. Handling may cause skin irritation as the plant produces a poisonous milky sap that contains latex which is toxic on ingestion and highly irritant externally, causing photosensitive skin reactions and severe inflammation, especially on contact with eyes or open cuts. The toxicity can remain high even in dried plant material. Prolonged and regular contact with the sap is inadvisable because of its carcinogenic nature.
For more details and photos of this plant visit: http://www.terrain.net.nz/friends-of-te-henui-group/weeds-by-scientific-names/euphorbia-lathyris-caper-spurge.html
Castor Oil Plant (Ricinus communis)
The broken mottled seeds are highly toxic if ingested. A severe allergic reaction in certain individuals following skin contact with broken seeds.
The toxic principle is ricin, a phytotoxalbumin, plus ricinine, an alkaloid.
Symptoms can be immediate or delayed. They are nausea, vomiting, abdominal pain, bloody diarrhoea, depression, trembling, sweating, convulsions and coma; may be fatal.
A video on the Castor oil plant
Cestrum (Cestrum species)
The poison part of Cestrum are the unripe berries which contain solanine-type glyco-alkaloids and atropine-like alkaloids.
If ingested the symptoms are headache, dizziness, hallucinations, nausea, vomiting, bloody diarrhoea, muscular spasms and nervousness, high temperature, salivation and sweating, paralysis and coma.
For more details of Cestrum visit:
Cherry laurel (Prunus several species)
Prunus poisonous parts are the wilted leaves, twigs (stems) and seeds if ingested due to cyanogenic glycoside, amygdalin.
Symptoms are gasping, weakness, excitement, pupil dilation, spasms, convulsions, coma and respiratory failure; may be be fatal.
For more details of Prunus visit:
Chilean Jasmine (Mandevilla laxa).
Mandevilla laxa is a climber with poisonous white latex in all parts. This sap has a milky appearance and flows whenever the vines are broken. Contact with this sap may irritate skin and eyes.
If any part including the flowers are ingested a gastric upset will occur. The effects are not usually severe.
Chinaberry (Melia azedarach)
The yellow fruit is poisonous if eaten by humans and animals although many birds seem partial to them and are not affected. Tranortriterpenes have been isolated and identified as the main toxic constituents of the fruit.
The poisonous fruit are toxic to humans and some other mammals. Pigs are the most susceptible.
In humans the first symptoms of poisoning appear a few hours after ingestion. They may include loss of appetite, vomiting, constipation or diarrhea, bloody faeces, stomach pain, pulmonary congestion, cardiac arrest, rigidity, lack of coordination and general weakness. Death may take place after about 24 hours. 6 to 8 fruits have been reported to cause death in young children.
The leaves are also toxic and deadly to grazing animals.
For more details on this tree visit: http://www.terrain.net.nz/friends-of-te-henui-group/trees-exotic-botanical-names-m-to-q/melia-azedarach-chinaberry.html
Contact with chrysanthemum plants (100 to 200 species) can cause a variety of skin symptoms in susceptible people. chrysanthemums contain toxins such as lactones, pyrethrums and sesquiterpene.
Repeated exposure increases the risk of developing symptoms. Symptoms that can develop are itchy skin, urticaria, localized skin swelling and allergic dermatitis. Washing the areas can help otherwise the use of corticosteroids might be needed.
Chrysanthemum plants can be very toxic to cats, dogs and horses and can cause vomiting, diarrhoea, nausea, incoordination and hyper-salivation in animals.
Comfrey (Symphytum officinale and its hybrids).
Comfrey contains at least eight pyrrolizidine alkaloids. Comfrey has been used in folk medicine as a poultice for treating burns and wounds. However, internal consumption, such as in the form of herbal tea, is discouraged, as it has been highly debated about whether it can cause serious liver damage.
Read an article on Symphytum officinale published by Cornell University at:
Daffodil (Narcissus several species)
The bulbs are toxic only if large quantities are eaten. Skin irritation can be severe.
Toxic principles in Narcissus are phenanthridine alkaloids such as lycorine, also calcium oxalate crystals.
Symptoms are nausea, vomiting, diarrhoea, salivation, trembling, convulsions; may be fatal. Contact dermatitis ("lily rash") following handling of bulbs, flowers, and stems.
A video on daffodils
For more details of Narcissus visit:
Daphne (Daphne several species)
The highly toxic parts are fruits and leaves if eaten.
The toxic principle is diterpenoid (mezerein).
Some people may develop skin irritation with blisters upon contact with leaves.
Symptoms are swelling of lips and tongue, thirst, difficulty of swallowing, nausea, vomiting, internal bleeding with bloody diarrhoea, weakness, and coma; may be be fatal.
For more details of Daphne visit:
Deadly Nightshade (Atropa belladonna)
All parts of this plant are highly toxic but it is the mainly the slightly sweet enticing berries that are eaten.
The toxic compounds are tropane alkaloids, notably atropine, hyoscine, hyoscyamine and toxic components.
Symptoms which may be slow to appear but can last for several days are fever, rapid pulse, dilation of pupils, hot and dry flushed skin, headache, dry mouth, difficulty of swallowing, burning of the throat and hallucinations. Coma and convulsions often precede death.
The Information below is courtesy of Landcare Research New Zealand Ltd.
True deadly nightshade is extremely rare in New Zealand. Unfortunately, this name is mistakenly applied to black nightshade (Solanum nigrum). The two are easily distinguished: deadly nightshade is a large plant over a metre high when mature, and has large, bell-shaped, brownish-purple flowers followed by large, egg-shaped black berries. Black nightshade is a much smaller plant (about half the height of deadly nightshade when mature), and has small white star-shaped flowers followed by little black berries, similar to black currants.
A video on Atrpa belladonna
Death Cap mushroom (Amanita phalloides)
This fungus is highly toxic, and is responsible for the majority of fatal mushroom poisonings worldwide. The poisons which are found throughout the cap, gills, stem and spores attack the body by inhibiting the formation of certain proteins in the liver and kidney, leading to coma and death. The toxicity is not reduced by cooking, freezing, or drying. The ingestion of 3 g of Death Cap tissue is considered lethal.
Amanita phalloides grow under and around grow around oak and chestnut trees in a few places in New Zealand.
How to identify a Death cap mushroom visit:
A young death cap emerging from its universal veil.
Adult Death Cap.
Dimorphotheca daisy (Osteospermum species)
Osteospermum is a toxic plant genus and all parts if ingested causes cyanide poisoning. When a plant cell is damaged, linamarase, the enzyme present causes linamarin to be split into glucose, hydrocyanic acid and acetone.
Symptoms are laboured breathing, tremors and muscular contractions, some times followed by convulsions, paralysis, and loss of consciousness; may be be fatal.
For more details of Osteospermum visit:
Dumb Canes (Dieffenbachia species). They are popular as house plants.
The sap is very poisonous because the plants cells contain needle-shaped calcium oxalate crystals called raphides and a toxic protein called asparagine.
These toxic chemicals cause burning in mouth or throat, excessive drooling, damage to cornea of the eye, eye pain, diarrhoea, hoarse voice, nausea, vomiting and localized swelling.
Blistering and swelling in the mouth may be severe enough to prevent normal speaking and swallowing. However, these effects are rarely life-threatening.
Elephant Ear (Alocasia macrorrhiza)
This plant contains poisonous agents which are calcium oxalate crystals and the presence of needle-shaped raphides in the plant cells. Just touch can lead to skin and eye irritation in some interviduals. When eaten it causes immediate pain, burning sensation and swelling of the lips, tongue and mouth. Deaths have been reported.
As first aid rinse lengthily, administer small amount of milk, do not induce vomiting.
For more details of Alocasia macrorrhiza visit:
European Beech (Fagus sylvatica)
Unripe, raw nuts nuts (seeds) are lightly toxic to humans if eaten in large quantities due to a saponic glycoside that they contain.
Symptoms: Stomach upset.
False Acacia (Robinia pseudoacacia)
Robinia pseudoacacia is toxic and the poisoning of humans and livestock are occasionally reported. The leaves, young shoots, pods, seeds and the bark contain toxic components. Poisoning is due to the toxic protein toxalbumin robin and the alkaloid robinine. These toxins affect the gastrointestinal tract as well as the nervous system. Humans may display depression, weakness, dilated pupils, vomiting, bloody diarrhea, weak pulse, coldness of arms and legs, paleness, and shock.
Horses are particularly at risk, but all animals ingesting the plant may be poisoned. Horses that consume the plant show signs of anorexia, depression, incontinence, colic, weakness, and cardiac arrhythmia. Symptoms usually occur about 1 hour following consumption, and immediate veterinary attention is required.
For more detail on this tree visit:
Five Finger or Whauwhaupaku (Pseudopanax arboreus).
Since it belongs to the ivy family, parts of plant are poisonous if ingested.
For more details on Pseudopanax arboreus visit:
The berries of this genus are mildly poisonous as their seeds contain cyanogenic glycosides and can cause mild gastro-intestinal problems when eaten raw in large quantities.
Yellow berries Red berries
Foxglove (Digitalis purpurea)
The highly toxic parts are the leaves, flowers and seeds when ingested due to a cardiac glycoside called digoxin. There is confusion with Symphytum (comfrey) and the leaves have been brewed into a toxic tea.
Symptoms are nausea, vomiting, diarrhoea, stomach pain, severe headache, irregular and slow pulse, tremors, unusual colour visions and convulsions; may be be fatal.
A video on foxglove
For more details of Digitalis purpurea visit:
Giant hogweed (Heracleum mantegazzianum)
Heracleum mantegazzianum sap is highly toxic and poisonous to humans if one is exposed either by touch or dust that is raised by machinery (e.g. weed eaters). Exposure will cause 'photo dermatitis' or 'photosensitivity'. The skin may become very sensitive to sunlight and one may suffer from blistering, pigmentation and long-lasting scars.
Contact with the eyes can lead to temporary or permanent blindness. Body areas which come into contact with this plant should be washed immediately and protected from direct sunlight, seek medical advice. Always wear gloves, cloths for skin protection and glasses for eye protection.
The serious reactions to this plant are due to the furocoumarin derivatives in the leaves, roots, stems, flowers, and seeds of the plant.
For more details on this plant visit: http://www.terrain.net.nz/friends-of-te-henui-group/weeds-by-scientific-names/heracleum-mantegazzianum-giant-hogweed.html
Gloriosa Lily (Gloriosa superba).
All parts are poisonous, especially the tuberous roots. The toxic is so poisonous
it will cause human and animal fatalities if ingested.
This plant contains high levels of colchicine, a toxic alkaloid. It also contains
the alkaloid gloriocine. Within a few hours of the ingestion of a toxic amount of plant material, a victim may experience nausea, vomiting, numbness, and tingling around the mouth, burning in the throat, abdominal pain, and bloody diarrhea, which leads to dehydration. As the toxic syndrome progresses, rhabdomyolysis, ileus, respiratory depression, hypotension, coagulopathy, haematuria, altered mental status, seizures, coma, and ascending polyneuropathy may occur. Poisonings can occur when the tubers are mistaken for sweet potatoes or yams and are eaten.
The plant can be dangerous for cats, dogs, horses, and livestock as well.
Golden chain tree (Laburnum anagyroides)
All parts of this plant are highly toxic if ingested. The toxic principle is an alkaloid called cytosine which is extremely poisonous to humans as well as goats and horses. The symptoms are nervousness, stomach and intestinal irritation with nausea, vomiting, and diarrhoea; irregular pulse, convulsions and coma.
For more details on this tree visit: http://www.terrain.net.nz/friends-of-te-henui-group/weeds-by-scientific-names/laburnum-anagyroides-golden-chain.html
Hellbore (Helliborus species)
The entire plant is toxic. Hellebores contain glycosides named helleborin, helleborein, helleborigenin and protoanemonin in varying amounts according to the species.
Clinical signs of ingestion are drooling, abdominal pain and diarrhoea, colic, depression and death due to respiratory collapse. Cardiac problems can occur.\
Be very careful when harvesting Hellebore seeds as the sap is poisonous.
A video on the Helliborus
For more details of Helliborus visit:
Hemlock (Conium maculatum)
Every part of this plant is highly toxic if ingested, especially the fresh leaves and fruit which contains a volatile, oily alkaloid neurotoxin coniine. It is so poisonous that a few drops prove fatal to a small animal. Its leaves are mistaken for parsley, its roots for parsnips and seeds mistaken for anise.
The poisonous property occurs in all parts of the plant, though it is stated to be less strong in the root. Many children, too, have suffered by using whistles made from the hollow stems of the hemlock.\Symptoms are salivation, vomiting, diarrhoea, muscular weakness, paralysis, nervousness, trembling, dilation of pupils, weak pulse, convulsions and coma; may be be fatal.
A video on hemlocks:
For more details of Conium maculatum visit:
Henbane (Hyoscyamus niger).
All parts are highly poisonous, and neither drying nor boiling destroys the toxic principle. The leaves are the most powerful portion, even the odour of them when fresh will produce giddiness and stupor.
The chief constituent of Henbane is the alkaloid hyoscyamine, together with smaller quantities of atropine and hyoscine, also known as scopolamine.
Common effects of henbane ingestion in humans include hallucinations, dilated pupils, restlessness, and flushed skin. Less common symptoms, such as tachycardia, convulsions, vomiting, hypertension, hyperpyrexia and ataxia, have all been noted.
Henbane can be toxic, even fatal, to animals in low doses.
Holly (Ilex several species)
The poisonous part are the fruits and leaves which contain ilicin, ilexanthin and ilicic acid and a tannin plus cyanogenic glycosides.
The symptoms of a large dose, in the order of 30 or so berries, can cause nausea, vomiting, diarrhoea and abdominal pain. are nausea, vomiting, diarrhoea.
For more details of Ilex species visit:
Horse Chestnut (Aesculus hippocastanum)
The highly toxic parts are the raw seeds, leaf, bark, flowers and tea made from leaves and sprouts.
The toxic principles are glycoside aesculin, saponin aescin and possibly alkaloids.
Symptoms are muscle weakness and paralysis, dilated pupils, vomiting, diarrhoea, depression, paralysis and stupor; may be be fatal.
A short video on this tree
For more details of Aesculus hippocastanum visit:
Hydrangea (Hydrangea species)
Hydrangeas are moderately toxic if eaten, with all parts of the plant (bark, leaves and the flower buds) containing cyanogenic glycosides.
If ingested in large quantities the symptoms are nausea, abdominal pains, diarrhoea, vomiting, weakness, sweating laboured breathing, lethargy and coma. Sensitive individuals may develop contact dermatitis (itchy skin) from handling the plants.
Hydrangea paniculata is reportedly sometimes smoked as an intoxicant, despite the danger of illness and/or death due to the cyanide.
For more details of the Hydrangea species visit:http://www.terrain.net.nz/friends-of-te-henui-group/exotic-trees/hydrangea.html
Inkweed (Phytolacca octandra)
The poisonous parts are the berries, leaves and roots.
Their are toxicity is due to phytolaccatoxin and phytolaccigenin which are poisonous to mammals.
The symptoms are vomiting and diarrheoa occuring two hours after ingestion. Convulsions and difficulty in breathing may occur.
For more details of Phytolacca octandra visit:
Iceland Poppy (Papaver nudicaule and its cultivars)
All parts of plant are poisonous if ingested due to morphine and other alkaloids in its milky latex.
Symptoms from ingestion are stupor, coma, shallow and slow breathing, respiratory and circulatory depression
This plant is also toxic to animals, horses, cattle, and sheep were poisoned when discarded plants were given to livestock
Iris (Irus several species)
The poisonous parts are the rhizomes, bulbs and stem.
The toxicity is due to the glycosides irisin, iridin or irisine.
When the gastrointestinal tract become affected the symptoms are nausea, violent diarrhoea and abdominal burning and fever. Iris can also cause skin irritation or dermatitis.
Italian Arum (Arum italicum).
All parts are extremely poisonous including the sap. The toxic component is
calcium oxalate which is a needle shaped crystal that can irritate the skin and
if ingested will result in the throat swelling, breathing difficulties, burning pain,
and stomach upset.
The plants berries are orange but they have an acrid taste which means that
large amounts are rarely ingested and serious harm is unusual..
For more details on Arum italicum visit:
Ivy (Hedera helix)
All parts are poisonous including the berries.
The toxic principles are triterpenoid saponins and polyacetylene compounds which when ingested will give the following symptoms, burning sensation of throat, delirium, stupor, convulsions, hallucinations, fever, and rash.
Severe skin irritation with redness, itching, and blisters following contact with cell sap.
For more details of Hedera helix visit:
Jasmine (Star jasmine) Trachelospermum jasminoides
Star Jasmine is a member of the milkweed family. The entire plant is considered mildly poisonous and should not be consumed. Handling plant may cause skin irritation or allergic reaction due to its milk like sap. Beware this milk will stain clothes black.
Jerusalem Cherries (Solanum pseudocapsicum & Solanum diflorum)
The highly toxic parts if ingested are the berries and the leaves due to Solanocapsine and other alkaloids.
Symptoms are nausea, vomiting, salivation, drowsiness, abdominal pain, diarrhoea, weakness, respiratory depression.
For more details of Solanum pseudocapsicum visit:
Karaka (Cornyocarpus laevigatus)
The berries of Corynocarpus laevigatus (Karaka) are a major food source for New Zealand Wood Pigeon (Hemiphaga novaeseelandiae) but the kernels (nuts) contain the deadly toxic alkaloid karakin and various nitropropanoyl glucopyranoses (NPGs), twelve of which have been detected in karaka.
Karaka berries which contain highly poisonous kernels are attractive to both children, dogs and other animals. The berries fall from the trees between January and April. They are two and a half to four centimetres long, oval in shape and turn from green to orange. Owing to their foraging nature, dogs often hunt out and consume berry kernels. The veterinary association advised dog owners to take extreme care when walking their dogs. Berries remain toxic for a long time, even fruit up to 20 year old remain poisonous.
Signs of karaka poisoning include weakness, back leg paralysis, vomiting and convulsions that can lead to death. Symptoms can often be delayed by 24 to 48 hours.
Accounts from the 19th century record that extensive processing was used by Māori to convert the kernels to an edible form, and mention that if the processing was not done with the greatest care, poisoning would result with symptoms including violent convulsions and severe muscle spasms which could leave the limbs permanently fixed in contorted positions. Death resulted in a few cases.
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Khasia berry (Cotoneaster simonsii)
The berries are mildly poisonous and can cause a stomach upset if eaten.
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Kowhai (Sophora several species)
All parts of the plant but especially the ripe yellow seed are poisonous. Because the seed are hard they will take a lot of chewing to cause harm. If the seed are crushed before eating it is more likely that they will cause harm.
The major toxin is Cytisine and symptoms of poisoning include nausea, vomiting, increased heart rate, twitching of muscles or loss of coordination. Onset of these symptoms may occur within one hour. In extreme cases symptoms include paralysis and respiratory failure.
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Laburnum (Laburnum anagyroides)
All parts of this plant are highly toxic if ingested. The toxic principle is an alkaloid called cytisine.
The symptoms are nervousness, stomach and intestinal irritation with nausea, vomiting, and diarrhoea; irregular pulse, convulsions and coma; may be be fatal.
Found mainly in the South Island and southern half of North Island.
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Lantana (Lantana camara)
The highly toxic parts of this plant are the unripe, green berries and the leaves due to toxic triterpenes (lantadene, A lantadene B and icterogenin).
A skin irritation (dermatitis) from handling the leaves can occur but irritation is usually minor.
The symptoms of indigestion are vomiting, diarrhoea, dilated pupils, laboured respiration and ingestion; may be be fatal.
Found mainly in the warmer parts of the North Island and northern areas of South Island
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Larkspur (Delphinium several species)
All highly toxic parts of this plant is poisonous due to the alkaloids delphinine, ajacine, and others which cause neuromuscular paralysis.
Symptoms when ingested burning of lips and mouth, numbness of throat, increased salivation, intense vomiting and diarrhoea, muscular weakness and spasms, weak pulse, paralysis of the respiratory system, convulsions. Cardiac failure may occur, as can death from respiratory paralysis.
Lily of the Valley (Convallaria majalis)
All parts of Convallaria majalis are poisonous if large quantities are ingested due to the toxic effects of three cardiac glycosides convallarin, convallamarin, convallotoxin and saponins which cause gastrointestinal poisoning.
Convallotoxin is one of the most active natural substances affecting the heart.
Symptoms are irregular and slow pulse, abdominal pain and diarrhoea.
Found mainly in the South Island
Lily of the Valley shrub (Pieris species).
All parts of the Pieris species are highly poisonous especially the leaves and nectar from flowers due to over 30 different chemicals that act as "cardiac glycocides". They include a toxic principle grayanotoxins (formally called andromedotoxin). Ingestion can cause a disruption in sodium channels affecting the cardiac and skeletal muscle.
Symptoms of poisoning are tingling sensation, salivation, nose and eyes watering, nausea, vomiting, sweating, abdominal pain, headache, depression, weakness, convulsions, diarrhoea, heart arrhythmias, hypotension (drop in blood pressure); may be fatal.
For hundreds of years, "Lily of the Valley," (Pieris japonica) has been written into literature as the "poisonous plant" used in countless murders!
Marsh Marigold (Caltha palustris)
As is the case with many members of the family Ranunculaceae, all parts of this plant are poisonous and can be an irritant. Skin rashes and dermatitis have been reported from excessive handling of the plant. It is known to have kill cows.
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Milkweed (Euphorbia several species)
Species of Euphorbia and its relatives are amongst the National Poisons Centres top ten poisonous plants, consistently involved in children’s poisonings.
All parts of the plant is poisonous due to diterpene esters in the milky latex.
If handled dermatitis can occur. Skin irritation is usually minor and lasts only for a few minutes. Reaction might be greater in susceptible individuals when redness, swelling, blisters appear after some delay following contact with skin.
If ingested the symptoms are nausea, vomiting and diarrhoea.
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Monkshood, Aconite (Aconitum napeilus).
Like other species in the genus, A. napellus contains several poisonous compounds, including enough cardiac poison that it was used on spears and arrows for hunting and battle in ancient times.
Toxins can be absorbed through the skin by touching.
Marked symptoms may appear almost immediately, usually not later than one hour, and "with large doses death is almost instantaneous." Death usually occurs within two to six hours in fatal poisoning.
Morning Glory (Ipomoea species).
All or parts of this plant are poisonous.
The plant contains very powerful hallucinogenic drugs especially the seeds.
This plant contains toxic alkaloids (including Ergonovine, which bears a strong molecular resemblance to Lysergic Acid Diethylamide, or LSD) that discourage ingestion by grazing animals. This defence mechanism contributes to its prevalence as a weed species.
If ingested the symptoms are hallucinations, dilated pupils, nausea, vomiting, diarrhoea, drowsiness, numbness of extremities, and muscle tightness.
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Moth Vine or Cruel Vine (Araujia sericifera).
This serious weed pest has as a white latex in all parts of the plant that is
poisonous. Contact with its milky sap causes skin and eyes irritations, and occasionally even severe allergic reactions in susceptible people.
This species is considered to be poisonous to livestock and domestic animals (e.g. poultry and dogs). Poultry that have ingested the seeds and the toxin with in, developed central nervous system problems, incoordination of movement, loss of balance, and loss of muscular control. The lesions noted on autopsy were mainly catarrhal enteritis, congestion of the liver and spleen, and sub-meningcal congestion over the cerebellum.
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Mountain laurel (Kalmia latifolia)
All parts of Kalmia latifolia are toxic, especially the young shoots and leaves. The main toxin is called andromedo toxin. This toxin acts on blood circulation by lowering the blood pressure. This leads to drowsiness. The drowsiness allows the toxin to concentrate until it can attack the central nervous system. Convulsions occur, which can be quite severe, with death being preceded by a sort of creeping paralysis. The poison can be found in honey if apiarists have their hives near the plant.
The flowers are very attractive to children who are often made ill by trying to suck the sweet liquid out of the flowers. The nectar can induce vomiting, stomach pains and a runny nose. It is often enough to handle the flowers or leaves to receive a mild dose of ill effects. Whenever you handle mountain laurel you should be very careful about washing your hands.
Mountain laurel can produce fatal results in animals that eat too much of the leaves and stems. Goats are particularly vulnerable as are small birds like budgerigars.
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Mountain Tutu (Coriaria plumose)
All parts of the plant are highly toxic and the ingestion of its small black/red berries is the usual cause of poisoning.
Coriaria species contain a toxic hydroxytutin called hyenanchin. Little is heard of tutu poisoning in humans though indirect poisoning has occurred sporadically in recent times through the consumption of toxic honey. Bees that collect honeydew exudates from vine hopper insects (Scolypopa sp.) that have fed on the sap of Coriaria species producing a honey containing tutin. Since 1889 there have been 141 reported cases of illness from ingesting toxic honey and four cases of death in New Zealand.
Symptoms of honey containing the toxic hydroxytutin is vomiting, giddiness, delirium, great excitement, convulsions and coma, ending in death.
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Natal lily (Clivia miniata)
It contains small amounts of lycorine, making it poisonous. Lycorine is a toxic crystalline alkaloid found in various Amaryllidaceae species, such as Clivia miniata, surprise lilies (Lycoris), and daffodils (Narcissus). It may be highly poisonous, or even lethal, when ingested in certain quantities. Daffodil bulbs are sometimes confused with onions, leading to accidental poisoning.
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New Zealand Blueberry (Dianella nigra) also called Dianella intermedia
The attractive violet berries which appear December - May are poisonous and should not be eaten.
Though poisonings are rare Dianella nigra berries were implicated in the death of an infant in the late 1800s.
The symptoms of ingestion of berries of the Dianella species are respiratory distress and staggering.
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Ngaio (Myoporum laetum & Myoporum insulare)
The Myoporum species are very poisonous plants and are mainly grow near the sea, either wild or in cultivation. They are easily identified by the numerous pale leaf spots (pellucid glands) seen when held to the light, and by the purple berries.
Both the native ngaio (M. laetum) and Australian ngaio (M. insulare) should be regarded as equally harmful.
The tree contains a liver toxin ngaione.
Symptoms vary depending on the degree of exposure and hence extent of the liver damage or injury.
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Oleander (Nerium oleander)
Oleander is one of the most dangerous poisonous plants. If this plant is being burnt the smoke is toxic.
The whole plant is highly toxic due to the cardiac glycosides oleandrin, neriine, known for their powerful effect on the heart.
Oleander causes intense abdominal pain, vomiting, diarrhoea, drowsiness, dizziness, visual disturbances, rapid pulse, an irregular heartbeat and heart malfunction, often causing death.
The sap if in contact with the skin can cause dermatitis, blistering, irritation and soreness.
Poisoning have occurred when using oleander sticks for sausage and marshmallow roasts and drinking water in which the flowers have been placed.
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Peach (Prunus pewrsica)
The highly toxic parts are the wilted leaves, twigs (stems), seeds due to the toxic cyanogenic glycoside, amygdalin which, on hydrolysis, yield hydrogen cyanide.
Symptoms form ingestion are gasping, weakness, excitement, pupil dilation, spasms, convulsions, coma, respiratory failure; may be be fatal.
Myths and rumours about the toxicity of the poinsettia plant are common. While the genus (Euphorbia) to which the poinsettia plant belongs does contain some highly toxic plants, the popular poinsettia itself is not toxic.
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Poison Ivy (Toxicodendron radicans) Synonyms: Rhus radicans, Rhus toxicodendron
Toxicodendron radicans is not a true ivy. Its sap contains a mixture of pentadecylcatechols, which collectively are called urushiol. After injury, the sap leaks to the surface of the plant where the urushiol causes an induced contact dermatitis in most people that touch it. The symptoms of this allergic reaction are an itching, irritating, and sometimes painful rash with blisters. In extreme cases, a reaction can progress to anaphylaxis (serious allergic reaction that is rapid in onset and may cause death). Around 15% to 30% of people have no allergic reaction to urushiol, but most people will have a greater reaction with repeated or more concentrated exposure. A poison ivy rash usually develops within a week of exposure and can last anywhere from one to four weeks, depending on severity and treatment. In rare cases, poison ivy reactions may require hospitalization.
If poison ivy is burned and the smoke then inhaled, this rash will appear on the lining of the lungs, causing extreme pain and possibly fatal respiratory difficulty. If poison ivy is eaten, the mucus lining of the mouth and digestive tract can be damaged.
Immediate washing with soap and cold water or rubbing alcohol may help prevent a reaction. Hot water should not be used, as it causes one's pores to open up and admit the oils from the plant.
Poppy (Papaver several species)
The highly toxic part of a poppy is the milky sap from all parts, but mainly the fruits.
Toxic principles is morphine and other alkaloids.
Symptoms from ingestion are stupor, coma, shallow and slow breathing, respiratory and circulatory depression; may be be fatal.
Poppy seeds used as topping of breads are safe.
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Poroporo (Solanum laciniatum)
The highly toxic parts of this plant are the leaves and berries.
The principle toxin is a solanine alkaloid.
Symptoms from ingestion are nausea, vomiting, salivation, drowsiness, abdominal pain, diarrhoea, weakness, respiratory depression; may be fatal.
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Potato (Solanum tuberosum)
Potatoes like other plants of the genus Solanum contain toxic compounds known as glycoalkaloids, of which the most prevalent are solanine and chaconine. These compounds, which protect the plant from its predators, are, in general, concentrated in its leaves, stems, sprouts, fruits and are in small concentrations in the tubers.A normal tuber has 12–20 mg/kg of glycoalkaloid content while a green tuber contains 250–280 mg/kg, and the tuber’s green skin contains 1500–2200 mg/kg. Due to the green parts being highly toxic, potato sprouts, the green skin and spoiled potato tubers should not be consumed. Never eat tubers if they look spoiled or green below the skin.
Symptoms occurring after ingestion are nausea, vomiting, salivation, drowsiness, abdominal pain, diarrhoea, weakness, respiratory depression; may be fatal.
Primula (Primula several species)
Poison Part of species of primula are glandular hairs on leaves and stems which can cause dermatitis.
The toxic principles are benzoquinone called primin and a flavone called primetin.
Symptoms can be a minor allergic skin irritation (redness, blisters, swelling), mainly on hands and face, following contact.
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Privet (Ligustrum several species)
The highly toxic parts of this plant are the leaves and the berries.
The toxic principles are the glycosides: syringin (ligustrin), shikimic acid.
Symptoms after ingestion are abdominal pain, nausea, vomiting, diarrhoea, headache, weakness, low blood pressure, cold and clammy skin possibly lasting 48 to 72 hours.
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Purple Toadflax (Linaria purpurea)
Linaria purpurea is toxic to stock and slightly toxic to humans.
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Rangiora (Brachyglottis repanda)
All parts of this tree are are highly poisonous.
The hepatotoxic substance a pyrrolizidine alkaloids is especially concentrated in the growing tips, flowers and the sap.
The leaves are poisonous to farm animals, particularly horses.
Poisoning causes Pyrrolizidine alkaloidosis and can result in damage to the liver, kidneys, heart, brain, smooth muscles, lungs, DNA, lesions all over the body, and could be a potential cause of cancer. Pyrrolizidine alkaloidosis is known as "Winton Disease" in New Zealand. “Winton” disease is cirrhosis of the liver in horses and cattle resulting from the chronic poisoning by toxic constituents of ragwort, rangiora and other noxious plants of the Asteraceae family eaten in the pasturage.
Honey produce by bees that gather pollen from the Rangiora flowers is toxic. In the past there are several reported deaths due to to the ingestion of this toxic honey.
The leaves are poisonous to farm animals, particularly horses.
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Red horse-chestnut (Aesculus x carnea)
The nuts are poisonous because they are rich in saponins. Although poisonous, saponins are poorly absorbed by the human body and so most pass through without harm. Saponins are much more toxic to some creatures, such as fish, and some of the worlds hunting tribes have traditionally put large quantities saponins containing flora in streams, lakes etc. in order to stupefy or kill the fish.
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Rhododendron (Rhododendron species)
All parts of this plant are extremely toxic to humans and animals due to a toxic resin, grayanotoxin,with the leaves being the most potent. The sucking of nectar out of flowers may produce a serious illness.
Symptoms of ingestion usually appear within 6 hours of ingestion.
Grayanotoxin produces gastrointestinal irritation with some haemorrhage, secondary aspiration pneumonia, and sometimes renal tubular damage and mild liver degeneration.
The consumption of foliage by animals will produce severe toxicosis. Since rhododendrons are more likely to retain green leaves year round most toxicoses occur in the winter and early spring, when other forage is unavailable.
Clinical signs of affected animals: They may experience anorexia, depression, acute digestive upset, hypersalivation, nasal discharge, epiphora, projectile vomiting, frequent defecation, and repeated attempts to swallow. There also may be weakness, incoordination, paralysis of the limbs, stupor, and depression. Aspiration of vomitus is common in ruminants and results in dyspnea and often death. Pupillary reflexes may be absent. Coma precedes death. Animals may remain sick for more than 2 days and gradually recover.
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Rhubarb (Rheum rhaponticum)
The toxic part of rhubarb are the raw leaves and they remain toxic even after cooking.
Toxic principles are anthraquinone glycosides and soluble oxalates and also calcium oxylate crystals.
Symptoms of ingestion are abdominal cramps, burning of mouth and throat, headache, weakness, nausea and vomiting, coma; may be fatal only if large quantities are eaten.
Spanish Broom (Spartium junceum)
The whole plant is toxic, especially the seeds. The risk with this plant is children playing with seeds and their accidental or intentional ingestion.
The toxic principle is sparteine that has effects like that of nicotine. It exerts quinidine like effects on the heart. It reduces the sensitivity and conductivity of cardiac muscle.
Small doses stimulate and large doses paralyse autonomic ganglia. Peripherally, it has a fairly strong curare-like action, arresting respiration by paralysing the phrenic nerve. (Martindale, 1989).
Symptoms of ingestion are vomiting, diarrhoea, tachycardia, somnolence, painful breathing, lowering of heart pulse and may be death.
Spindle tree and Japanese spindle tree (Euonymus europaeus and E. japonicus)
All parts of these tree are highly toxic but it is the berries which cause the most harm having poisoned children as well as goats, horses, and sheep. Children are attracted to the mature fleshy orange fruits, which contain seeds with cardiac glycosides and alkaloids.
Symptoms appear up to 12 hours after ingestion and involve diarrhoea, vomiting and stimulation of the heart. Larger doses can cause hallucinations, loss of consciousness and symptoms similar to meningitis. Ingestion can result in liver and kidney damage and even death.
Taro (Colocasia esculenta)
Taro is poisonous in its raw form. Uncooked the plant is toxic due to the presence of calcium oxalate and the presence of needle-shaped called raphides in the plant cells. However, the toxin can be minimized and the tuber rendered palatable by cooking, or by steeping in cold water overnight.
Symptoms of ingestion in its raw form are a severe pain in the mouth, burning and swelling of lips, mouth, tongue, and throat, difficulty of speech.
Thorn Apple (Datura stramonium)
All parts, mainly seeds and leaves are toxic if ingested due to tropane alkaloids.
Symptoms are hot, dry, and flushed skin, hallucinations, pupil dilation, headache, delirium, rapid and weak pulse, convulsions, coma and in severe cases death if large quantities are eaten.
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Titoki (Alectryon excelsus)
Many plants in the Alectryon family are poisonous.
The round black seeds are best avoided despite limited information on their toxicity.
They contains cyanogenetic glycosides which yield prussic acid.
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Tree Nettle (Urtica ferox)
The tree nettle is one of New Zealand's most poisonous native plants. Brushing the plant produces a stinging on the skin of varying intensity.
The leaves and stalks have numerous white stinging hairs (trichomes), up to 6mm long. These break after piercing the skin, injecting toxins into the tissues, giving rise to pain and rash.
Formic acid is present and responsible for the initial pain but the longer term effects are caused by histamine, acetylcholine and 5-hydroxytryptamine.
There have been cases of dogs and horses developing neurological problems, with respiratory distress and convulsions within minutes of exposure, often dying within hours, although some do recover. There are also reports of human poisoning in botanical references or the press. Connor, in his book, The Poisonous Plants in New Zealand, mentions a group of trampers who developed loss of coordination for three days after being stung. In another instance, a typist developed tingling numbness in the hand after grasping a nettle bush, preventing her from typing for five days. There are also reports of severe headaches, blurred vision and extreme fatigue. A fatal poisoning was described in 1961, when a young man died of paralysis and respiratory problems several hours after walking through a patch of tree nettles. Thanks to the New Zealand Plant Conservation Network for some of the above text.
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Tree of Heaven (Ailanthus altissima)
It is reported all parts of this tree is poisonous as it contains a quinone irritant, 2,6-dimethoxybenzoquinone, as well as active quassinoids. Ingestion causes nausea, vomiting and muscular relaxation. The leaves are toxic to domestic animals (Perry, 1980). The odour of the foliage can cause headache and nausea...rhinitis and conjunctivitis in some individuals. Contact dermatitis can occur and the pollen can cause hay fever.
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Tutsan (Hypericum androsaemum)
Tutsan is member of the St. John's-Wort family. It is a shrub-like plant of damp hedgerows and woodlands.
The berries which turn from green, to red and finally ripen to a purple-black colour are slightly poisonous especially to children.
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Tutu (Coriaria species)
All parts of the plant is poisonous and the ingestion of its small black/red berries is the usual cause of poisoning.
Coriaria species contain a toxic hydroxytutin called hyenanchin. Little is heard of tutu poisoning in humans though indirect poisoning has occurred sporadically in recent times through the consumption of toxic honey. Bees that collect honeydew exudates from vine hopper insects (Scolypopa sp.) that have fed on the sap of Coriaria species producing a honey containing tutin. Since 1889 there have been 141 reported cases of illness from ingesting toxic honey and four cases of death in New Zealand.
Symptoms of indesting honey containing the toxic hydroxytutin is vomiting, giddiness, delirium, great excitement, convulsions and coma, ending in death.
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Wax tree or Rhus (Toxicodendron succedaneum)
Toxicodendron succedaneum (use to be called Rhus succedanea) is a highly
toxic, allergy-causing tree. The plant contains the carcinogenic
shikimic acid (shikimate) which causes severe dermatitis beginning with a
rash, redness, itching and blisters wherever skin comes into contact with the
plant or its sap. The rash is often accompanied by localised swelling of the
face, arms and legs.
This tree is now classed as a noxious weed in New Zealand and Australia.
It is found mainly in the North Island and northern South Island.
White Cedar, Persian lilac (Melia azederach)
The bunches of yellow fruits left behind when the leaves fall are poisonous to humans if eaten in quantity.
Like in its relatives, tetranortriterpene neurotoxins and also possibly a saponin constitute the important toxic principles.
The first symptoms of poisoning appear a few hours after ingestion. They may include loss of appetite, vomiting, constipation or diarrhoea, bloody faeces, stomach pain, pulmonary congestion, cardiac arrest, rigidity, lack of coordination and general weakness. Death may take place after about 24 hours.
Found mainly in the North Island.
Wisteria ( Chinese and Japanese)
All parts of the Wisteria plant are toxic as they contain a wisterine glycoside and a lectin. Wisterine is a saponin which is toxic if ingested and may cause dizziness, confusion, speech problems, nausea, vomiting, stomach pains, diarrhea and collapse. The seeds of all Wisteria species are especially poisonous. The clinical signs: vomiting (sometimes with blood), diarrhea and depression.
Poisoning could require treatments such as intravenous hydration and anti-nausea pills.
Wisteria is also toxic to dogs, cats and horses.
Woolly Nightshade (Solanum mauritianum)
All parts of the Solanum mauritianum plant are poisonous to humans, especially the berries. Human fatalities have resulted from the consumption of the berries.
The main toxic compound is the alkaloid, solasodine, with the highest content in the unripe green berry. Solauricine, solauricidine, and solasodamine have also been found in Solanum mauritianum.
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Yarrow (Achillea millefolium)
The toxic parts are the leaves and flowers.
Toxic principles are glycoalkaloids (achillen), monoterpenes, sesquiterpene lactones.
Humans can develop a skin irritation after contact and exposure to sunlight.
It is toxic to dogs, cats and horses which after ingestion will show symptom of vomiting, diarrhoea, depression, anorexia and hypersalivation.
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Yellow horned poppy (Glaucium flavum)
All parts of the plant, including the seeds and the roots which are especially poisonous.
The active principles are the alkaloids: glaucine, protopine,chelidonine, chelerythrine, cordydine and the acids: fumaric and chelidonic. These toxins can produce a range of symptoms. If small amounts are ingested the symptoms can be stomach ache, nausea or vomiting, thirstiness, dryness of the mouth, breathing difficulties, decreased of heart beat. In strong intoxications: mental confusion, numbness of the members, hypotension, respiratory failure resulting in death. It is also toxic to livestock.
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Yew (Taxus baccata)
The highly toxic parts are the bark, leaves and the seeds.
The toxic principle is the alkaloid taxine.
Symptoms on ingestion are nervousness, trembling, slow pulse, pupil dilation, difficult breathing, abdominal pain, vomiting, diarrhoea, weakness, convulsions; may be fatal.
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