Cicuta

From Wikipedia, the free encyclopedia

  (Redirected from Water Hemlock)
Jump to: navigation, search
Cicuta
Cicuta virosa
Cicuta virosa
Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Apiales
Family: Apiaceae
Genus: Cicuta
L.
Species

Cicuta bulbifera
Cicuta douglasii
Cicuta maculata
Cicuta virosa

Cicuta (Water Hemlock or Cowbane) is a small genus of four species of highly poisonous flowering plants in the family Apiaceae, native to temperate regions of the Northern Hemisphere, mainly North America and Europe. They are perennial herbaceous plants which grow up to 2 m tall. The species grow in wet meadows, along streambanks and other wet and marshy areas.

Although water hemlock bears a superficial resemblance to poison hemlock (Conium genus)—and is a member of the same family—the species are distinct.

Contents

[edit] Appearance

The stems are smooth, branching, swollen at the base, purple-striped, or mottled (C. malculata only), and hollow except for partitions at the junction of the leaves and stem. The leaves are alternate, tripinnate, only coarsely toothed, unlike the ferny, lacy leaves found in many other members of the Apiaceae. The flowers are small, white and clustered in the umbrella shape so familiar to this family. An oily, yellow liquid oozes from cuts to the stems and roots. This liquid has a rank smell resembling that of parsnips, carrots or mice.

One reliable method to identify water hemlock is to examine the leaf veins. Water Hemlock is unique in the Parsley family in that it has leaf veins which terminate in the notches between the leaf tips rather than extend to the tip of the leaf as is found in the leaf structure of Angelica, Osha, Cicely, Osmorhiza and other useful medicinal members of the Parsley family. Water Hemlock bears a frightening resemblance to Osmorhiza (Western Sweet Cicely) and Angelica, and these plants can at times be found growing in the same habitat. However, Water hemlock lacks the distinctive anise-like "spicy celery" odor of Sweet Cicely and Angelica, and possesses a unique leaf vein structure which differenciates it from all other umbelliferates.

[edit] Toxicity

The plant is occasionally mistaken for parsnips, due to its clusters of white tuberous roots; this is an often fatal error, as the Cicuta is extremely poisonous. Indeed, some consider water hemlock to be North America's most toxic plant.[1] Cicuta is fatal when swallowed, causing violent and painful convulsions. Though a number of people have died from water hemlock poisoning over the centuries, and historically it has been used as a poison in Europe (even Socrates died by drinking cicuta), livestock have long been the worst affected (hence the name "cowbane"), causing death in as little as 15 minutes.[2][3]

The chief poison is cicutoxin, an unsaturated aliphatic alcohol that is most concentrated in the roots. Upon human consumption, nausea, vomiting, and tremors occur within 30–60 minutes, followed by severe cramps, projectile vomiting, and convulsions. There are occasional long-term effects, like retrograde amnesia.[4] Ingestion of water hemlock in any quantity can result in death or permanent neurological damage of the central nervous system.

Species

[edit] Similar species

These plants all have white flowers in large compound umbels. Therefore, these plants are confused with each other; the water parsnip, (swamp parsnip, sium suave) and the western water hemlock, (Cicuta douglasii, poison hemlock) or the spotted water hemlock (cicuta maculata, spotted water hemlock, spotted parsley, spotted cowbane). Water parsnip and water hemlock both have cluster of small white flowers shaped like umbrellas, and both have the same habitat near the shore line of lakes, and rivers. Water parsnip has leaves only once compound, and water hemlock has leaves which are three times compound. Water hemlock has a large swelling at the stem base. All water hemlock is highly poisonous.[5] Water parsnip is not poisonous.[6] The water hemlock has bracts at the base of each small flower cluster, not at the base of the main flower head.[7] The Water parsnip has small bracts at the base of flowers and main flower head as well.[8] The Yarrow, (Common Yarrow, Gordaldo, Nosebleed plant, Old Man's Pepper, Sanguinary, Milfoil, Soldier's Woundwort, Thousand-leaf (as its binomial name affirms), Thousand-seal or Achillea millefolium) also has many small white flowers in a cluster. However, the yarrow has feathery looking leaves which are pinnately separated into small narrow segments.[9] The cow parsnip (heracleum lanatum, Heracleum maxinium Indian Celery or Pushki, and Heracleum sphondylium, hogweed) is also confused in this group with similar flower groupings. However, the cow parsnip has large, broad leaves, and an unpleasant odour.[10]

[edit] External links

[edit] References

  1. ^ http://www.ars.usda.gov/Services/docs.htm?docid=9996 "USDA Poisonous Plant Research Products: Water hemlock". Accessed 1/27/07.
  2. ^ http://cal.vet.upenn.edu/poison/plants/ppwater.htm "Poisonous Plants Slides: Water Hemlock" Accessed 1/27/07.
  3. ^ USDA.
  4. ^ http://www.pubmedcentral.nih.gov/pagerender.fcgi?artid=1455113&pageindex=1#page David J. Costanza, M.D., and Vincent W. Hoversten, M.D., "Accidental Ingestion of Water Hemlock." Calif Med. 119: 78-82, Aug. 73.
  5. ^ "Cicuta maculata.". Retrieved on 2008-08-03.
  6. ^ "Traditional Plant Foods of Canadian Indigenous Peoples By Harriet V Kuhnlein, Nancy J.". Google books. Retrieved on 2008-08-03.
  7. ^ "Western Water Hemlock - Agriculture - Government of Saskatchewan". Retrieved on 2008-08-03.
  8. ^ "Water Parsnip - Agriculture - Government of Saskatchewan". Retrieved on 2008-08-03.
  9. ^ "Yarrow Achillea millefolium". Retrieved on 2008-08-03.
  10. ^ "Heracleum lanatum". University of Saskatchewan. Retrieved on 2008-08-03.
Retrieved from "http://en.wikipedia.org/wiki/Cicuta"
Personal tools