Poison Hemlock

Whether you’re in the country or in the city, Poison Hemlock is a pest that you don’t want to have around. It can cause severe health problems, so make sure you know what to do to avoid it.

Water hemlock

Known as the beaver poison or wild parsnip, water hemlock is a very dangerous plant. It thrives in wet and marshy areas and is known to cause serious complications and even death to humans and animals.

Poison hemlock is native to the Northern Hemisphere and is found in wetland areas, pasture grasses and along creeks and rivers. Its seeds are spread by mud or water.

It grows from two to eight feet tall and can be distinguished by its bulbous root structure. Its white flowers bloom in early summer and are common in clay loam soils.

It is also known as the Western water hemlock, cowbane, and beaver poison. It is native to marshes, streams, and irrigation ditches. It is a member of the Apiaceae family.

Western water hemlock is one of the most toxic plants in North America. In a study, it was estimated that a threshold dose could result in seizures and death. The toxicity of this plant can be increased if exposed to smoke.

This plant is easily confused with other edible plants like carrots and parsnips. However, the leaves of the water hemlock are much larger and more fern-like. It has a carrot-like odor.

In the spring, a water hemlock will start to grow and produce green fruit. When eaten, the toxin will affect the central nervous system. The resulting symptom is a great abdominal pain. The symptoms will last for 15 minutes to six hours.

In some cases, the toxin can be absorbed through the skin. It is not recommended that animals be fed on the plant after it is sprayed with an herbicide. This will prevent the development of seed banks and prevent livestock from being poisoned.

When applying an herbicide, make sure that it is legal to use. Read the label carefully to know the restrictions. It is important to avoid the plant for three weeks after spraying.

The American Association of Poison Control Centers recorded four deaths from poisoning in the 1989-1992 period. It is highly recommended that livestock be removed from infested areas.

It is also recommended that people wearing gloves take extra care when pulling the plant. It is best to avoid consuming the roots because they are very toxic.


Among the many weeds found in North America, poison hemlock is one of the most toxic. It grows in disturbed areas, such as fencerows, ditches, and pastures. It produces abundant seeds and can outcompete native plants and animals. If not controlled, poison hemlock can easily become a dominant species in riparian areas and other disturbed areas.

Poison hemlock is a biennial plant that grows 6-10 feet tall. Its fern-like leaves have purple spots on the base. The stems are hollow and hairless. It has a strong, pungent odor.

Symptoms of poison hemlock appear within 20 minutes to 3 hours. The plant is highly toxic to livestock, humans, and insects. If ingested, it is fatal.

Its seeds are toxic to animals, as well as humans. Its main stem is hollow and has a long white taproot. Its leaves are fern-like and alternate. The flowers are white and cluster in an umbel. Its fruits are ovoid and gray-brown.

It can be found throughout North America. It is most common in the lower elevations. It grows in wet, shady locations and along rivers and streams. It is also common in no-till and fallow fields. Its invasive nature makes it difficult to eradicate.

Its seeds are small, round, and have ridges. They can live for years in the soil. They can be eaten by birds and other animals. They can be spread by water, fur, and rodents. It is very important to control poison hemlock early in its life cycle.

Poison hemlock can be controlled using herbicides. These include 2,4-D, glyphosate, and dicamba. These herbicides are effective when applied in the spring or fall. However, it is important to wear personal protection and to follow label directions.

It is also recommended to remove poison hemlock before it flowers. It takes two years for the plant to complete its life cycle. If not managed, it will form dense stands that can outcompete native vegetation.

If you are dealing with a large infestation, it may be necessary to cut it with a mower. It can also be burned, but this can release toxins. It is best to wear protective clothing, take frequent breaks, and wash your hands after handling the plant.


Symptoms of poison hemlock include muscle pain, weakness, trembling, and paralysis of respiratory muscles. There is also a burning sensation in the digestive tract. If this plant is consumed, it can be fatal.

It is also toxic to animals. This plant is deadly to humans and has been used as a means to kill prisoners in ancient Greece.

When ingested, the seeds of poison hemlock can enter the body through the mouth, nose, or eyes. These toxins are found in the sap of the plant and can affect the nervous system. If the toxins reach the nerves, they can cause paralysis.

If a person ingests a large amount of hemlock, he may die within three hours. The hemlock plant is toxic to livestock and can even damage the nerves and central nervous system. The animal may be unable to feed, have a cleft palate, or may have skeletal deformities. Several studies have shown that people inhaling the plant’s fumes can suffer from respiratory failure.

The plant is found throughout the United States. It grows in wet, moist areas. It can contaminate hay, grain fields, and perennial crops. If you are exposed to hemlock, you should seek medical treatment immediately.

The alkaloids present in the plant are derived from pyridine. The most toxic are y-coniine and gamma-coniine. There are eight piperidine alkaloids in the plant.

Some symptoms of poison hemlock are similar to lupine-induced crooked calf disease. However, poison hemlock is much more dangerous to humans. In fact, it is one of the most dangerous plants on earth.

Because of its potential to kill, it is important to learn the symptoms of poison hemlock. The quicker you can get an accurate diagnosis, the better the outcome will be.

A doctor can administer an antidote to treat the symptoms of poison hemlock. In some cases, mechanical ventilation has been provided. If your horse is in the recumbent position, you should also provide activated charcoal. Activated charcoal helps to absorb hemlock toxins.

If you suspect that your horse has been ingesting hemlock, seek medical help. It is recommended that you bring a sample of the poisonous plant to the veterinarian.


Symptoms of poison hemlock poisoning include profound neuromuscular weakness, trembling, and muscular weakness. The plant also causes respiratory paralysis and can lead to collapse. If not treated immediately, the condition can be lethal.

Toxicological studies on animals have documented the presence of alkaloids, which are the primary component of the plant’s toxicity. These include coniine, a potent alkaloid which is similar to nicotine, and eight piperidine alkaloids. The age and season of the plant can influence the concentration of these alkaloids. Activated charcoal has been recommended as a preventive measure.

In a case study, a 21-year-old man ingested poison hemlock in 2011. The patient had a full neurological recovery. However, he required mechanical ventilation for 14 days. A suicide note was found in his left arm, stating that he had injected poison hemlock. He had fresh track marks on the left arm. This is the first known case of a surviving patient having delayed neurological sequelae.

The LD50 of coniine is lower than that of oral toxicity. Several cases of prolonged neuromuscular toxicity have been reported, but previous case reports have not documented the persistence of encephalopathy after ingestion.

The most commonly reported cases of toxicity involve both animals and humans. In the United States, poison hemlock is found in damp and undisturbed regions. It is often mistaken for water hemlock, which is an edible plant. The difference is in the size and shape of the plant’s leaves and root system. Although the leaf appearance is similar to parsley, the leaves have hollow, smooth stems, while the root system is more curved.

It is important to treat poison hemlock in dogs as quickly as possible, as it can be life-threatening if not addressed. If you suspect that your dog has eaten the plant, bring it to your veterinarian for treatment. Your vet will take a sample of blood and urine for urinalysis and biochemistry profile analysis. Activated charcoal will remove any remaining toxins and prevent further toxicity. If you don’t have access to a veterinarian, you can get rid of the plant yourself by vomiting. After vomiting, the plant can be removed from the dog’s system.