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Cicuta virosa

Please keep in mind that it is illegal to uproot a plant without the landowner's consent and care should be taken at all times not to damage wild plants. Wild plants should never be picked for pleasure and some plants are protected by law.
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Plant Profile

Flowering Months:
Apiaceae (Carrot)
Life Cycle:
Maximum Size:
150 centimetres tall
Ditches, fens, fields, marshes, ponds, riversides, scrub, swamps, water, waterside.

White, 5 petals
White flowers which appear in umbels measuring from 7 to 13cm across. Flowers have no lower bracts. 5 notched petals. Pollinated by flies and bees.
The spherical fruit is ridged with long styles. The sepal-teeth are prominent.
A hairless perennial species with 2 to 3-pinnate leaves. Purple-striped, smooth, hollow stems.
Other Names:
MacKenzie's Water Hemlock, Northern Water Hemlock, Water Hemlock.
Frequency (UK):

Other Information


Cicuta virosa, also known as water hemlock, is a species of poisonous plant in the carrot family (Apiaceae). It is native to wetland habitats in Europe, Asia, and North America, where it grows in marshes, swamps, and other areas with moist soil. The plant is a tall, herbaceous perennial with green, umbrella-shaped clusters of small flowers that bloom in the summer. Cicuta virosa is highly toxic and can be deadly if ingested. It contains several toxic compounds, including cicutoxin, which affects the central nervous system and can cause seizures, tremors, and other symptoms. The plant is sometimes confused with other species of hemlock, such as Conium maculatum, which is also highly toxic.


Cowbane (Cicuta virosa) is a species of plant in the Apiaceae (carrot) family that is native to North America, Europe, and Asia. It is a highly toxic plant and has a long history of use as a medicinal herb, as well as a poison.

Cowbane grows in wet areas such as marshes, swamps, and along streams, and has a long stem that can reach up to 6 feet in height. Its leaves are pinnate, meaning they are divided into several leaflets, and the plant produces small white flowers that bloom in the summer.

Despite its toxicity, Cowbane has been used for centuries in traditional medicine for a variety of ailments. It was used as a treatment for snake bites, rheumatism, and respiratory infections. The plant's toxic compounds, including cicutoxin and cicutol, have been found to have analgesic, anti-inflammatory, and antispasmodic properties, and have been used to treat pain and other symptoms.

However, it is important to note that Cowbane is a highly poisonous plant and should never be used without the supervision of a qualified medical professional. Ingesting even a small amount of the plant can lead to serious health problems, including convulsions, paralysis, and death.

Despite its toxic properties, Cowbane has also been used as a food source by indigenous peoples in North America, who would carefully prepare and cook the plant to remove its toxic compounds. The plant was also used in traditional Native American rituals, where it was burned as a sacred herb.

Cowbane is a fascinating plant with a long history of use for medicinal purposes and as a poison. Its toxicity makes it a dangerous plant to use, and it should never be used without the guidance of a qualified medical professional. If you come across Cowbane in the wild, it is best to leave it alone and avoid any contact with the plant.

In modern times, Cowbane is considered an invasive species in some areas, and its proliferation in natural habitats can have a negative impact on local ecosystems. It can displace native plant species, reducing biodiversity and altering the structure of ecosystems. Additionally, its toxic properties can harm wildlife, including birds, mammals, and reptiles, that consume the plant or its seeds.

Despite its negative impacts, Cowbane has been the subject of scientific study in recent years, and researchers are exploring its potential use as a source of natural remedies for various medical conditions. For example, studies have shown that cicutoxin and cicutol, the toxic compounds found in Cowbane, have the potential to be developed into treatments for conditions such as epilepsy, Parkinson's disease, and pain management.

Additionally, Cowbane has been used in phytoremediation, a process that uses plants to remove pollutants from the environment. In this process, Cowbane is planted in contaminated soil to absorb and break down harmful chemicals, such as heavy metals, and make the soil safe for other plants to grow.

Cowbane is a plant with a rich history and a complex relationship with humans. Its toxic properties have made it both a threat to wildlife and a potential source of new medical treatments. Its use in phytoremediation shows its potential to be a tool for environmental restoration, highlighting the importance of studying and understanding this plant.

It is also important to be aware of the dangers of Cowbane if you are out in the wild, or if you have children or pets who may be tempted to touch or taste the plant. Ingesting Cowbane can cause serious health problems, and even coming into contact with the plant can cause skin irritation or allergic reactions. If you suspect someone has ingested Cowbane, it is important to seek medical attention immediately.

When it comes to controlling Cowbane, it is best to leave it to professionals. Attempting to remove the plant on your own can be dangerous, and it is important to follow proper safety protocols when handling toxic plants. In some cases, herbicides may be used to control the spread of Cowbane, but care must be taken to minimize the impact on other plants and animals in the ecosystem.

In conclusion, Cowbane is a plant with a long history of use as a medicine and a poison, and it has a complex relationship with humans and the environment. Its toxic properties make it a threat to wildlife and a potential danger to humans and pets, and its potential as a source of natural remedies and its role in phytoremediation highlight the importance of understanding this plant and its impact on the world around us. If you come across Cowbane in the wild, it is best to leave it alone and take caution to avoid contact with the plant.

Distribution Map

Reproduced by kind permission of the BSBI.

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