''Cicuta douglasii'', the western water hemlock, is a very poisonous

perennial plant A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

in the family

Apiaceae Apiaceae or Umbelliferae is a family of mostly aromatic flowering plants named after the type genus '' Apium'' and commonly known as the celery, carrot or parsley family, or simply as umbellifers. It is the 16th-largest family of flowering plan ...

Description

Cicuta douglasii & Conium maculatum 1459205

The plant's roots are thick and

tuber Tubers are a type of enlarged structure used as storage organs for nutrients in some plants. They are used for the plant's perennation (survival of the winter or dry months), to provide energy and nutrients for regrowth during the next growin ...

ous, with many smaller tubers on the main one, allowing survival in wet conditions. The stem is tall with purplish spots. The inner tubers and stem bases can have horizontal chambers useful for identification. The leaves are alternate and compound pinnate. The leaflets are long and wide, with jagged edges. Its

inflorescence An inflorescence is a group or cluster of flowers arranged on a Plant stem, stem that is composed of a main branch or a complicated arrangement of branches. Morphology (biology), Morphologically, it is the modified part of the shoot of sperma ...

s are compound umbels about across, with many small, white flowers, which have two seeds each. The seeds germinate in spring, and flowers mature near the end of June and beginning of July.

Seed dispersal In Spermatophyte plants, seed dispersal is the movement, spread or transport of seeds away from the parent plant. Plants have limited mobility and rely upon a variety of dispersal vectors to transport their seeds, including both abiotic vectors ...

is by means of wind, water, machinery, clothing, and through transported soil. In addition to sprouting new plants from seeds, rootstocks can also produce new plants in the fall from the basal

meristem The meristem is a type of tissue found in plants. It consists of undifferentiated cells (meristematic cells) capable of cell division. Cells in the meristem can develop into all the other tissues and organs that occur in plants. These cells conti ...

. When these detach the following spring, they may form a new plant.

Distribution and habitat

Water hemlock is most abundant in

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

, and is indigenous to North America, where it grows primarily from the base of the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico ...

to the Pacific coast, stretching from

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S. ...

all the way to

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

. Water requirements limit this plant from inhabiting open rangelands. It grows in wet places such as marshes, stream banks, slough margins, ditches, meadows, and wet pastures.

Toxicity

The main distinguishing characteristic of western water hemlock is its toxicity. Cicutoxin is the

toxin A toxin is a naturally occurring organic poison produced by metabolic activities of living cells or organisms. Toxins occur especially as a protein or conjugated protein. The term toxin was first used by organic chemist Ludwig Brieger (1849 ...

that is produced, making water hemlock the most

poisonous plant Plants that produce toxins are referred to as poisonous plants. Plants that cause irritation on contact are also described as "poisonous". The toxins in poisonous plants affect herbivores, and deter them from consuming the plants. Plants cannot ...

in North America. Cicutoxin is a yellowish liquid that is prevalent in the roots. This

unsaturated alcohol Saturation, saturated, unsaturation or unsaturated may refer to: Chemistry * Saturation, a property of organic compounds referring to carbon-carbon bonds **Saturated and unsaturated compounds **Degree of unsaturation **Saturated fat or fatty acid ...

has a major impact on the central nervous system of animals. Early symptoms of cicutoxin poisoning include excessive salivation, frothing at the mouth, nervousness, and incoordination. These symptoms can progress to tremors, muscular weakness, seizures and respiratory failure. Ingestion of green materials of western water hemlock in amounts equivalent to about 0.1% of a person's body weight can even lead to death. In addition to being extremely hazardous to humans, this plant has an enormous impact on animals. As little as 0.2–0.5% body weight for sheep, 0.1% body weight for cattle, 0.5% body weight for horses, and 0.3% body weight for swine can be lethal. Death can occur within fifteen minutes of ingesting the toxin. It is one of the first plants to emerge in springtime, and has a very appealing odor. These characteristics, along with the fact that it grows in moist areas, make the plant very attractive, but deadly, to grazing animals.

References

External links

Calflora Database: ''Cicuta douglasii'' (Western water hemlock)

Jepson eFlora (TJM2) treatment of ''Cicuta douglasii''

U.C. CalPhotos gallery
{{Authority control Apioideae Flora of the Northwestern United States Flora of California Flora of Alaska Flora of Nevada Flora of Western Canada Flora of the Sierra Nevada (United States) Natural history of the California chaparral and woodlands Taxa named by Augustin Pyramus de Candolle Taxa named by John Merle Coulter Poisonous plants Flora without expected TNC conservation status