Western Water-hemlock (Common name)

General poisoning notes:

Western water-hemlock (Cicuta douglasii) is a native perennial plant found in wet soils in British Columbia. This plant is poisonous to all types of livestock and to humans. Many cases of poisoning have occurred in cattle, sheep, and horses. Pigs seem more resistant to the toxins, but they have still been poisoned. Humans have also been poisoned by this plant. Children are especially susceptible because ingestion of only one bite of the rootstock is sufficient to cause death. The onset of symptoms is so rapid that treatment may not be successful (Starrveld and Hope 1975, James and Ralphs 1986). See additional information in the general notes under Cicuta maculata.

References:

  • James, L. F., Ralphs, M. H. 1986. Water hemlock. Utah. Sci., 47(2): 67-69.
  • Panter, K. E., Keeler, R. F., Baker, D. C. 1988. Toxicoses in livestock from the hemlocks (Conium and Cicuta spp.). J. Anim. Sci., 66: 2407-2413.
  • Starreveld, E., Hope, C. E. 1975. Cicutoxin poisoning (water hemlock). Neurology, 25: 730-734.

Nomenclature:

Scientific Name:
Cicuta douglasii (DC.) Coult. & Rose
Vernacular name(s):
western water-hemlock
Scientific family name:
Umbelliferae
Vernacular family name:
parsley

Go to ITIS*ca for more taxonomic information on: Cicuta douglasii

References:

  • Agriculture Quebec. 1975. Noms des maladies des plantes du Canada/ Names of plant diseases in Canada. Quebec City, Que., Canada. 288 pp.
  • Alex, J. F., Cayouette, R., Mulligan, G. A. 1980. Common and botanical names of weeds in Canada/Noms populaire et scientifiques des plantes nuisibles du Canada. Revised. Agric. Can. Publ., Ottawa, Ont., Canada. 132 pp.
  • Bailey, L. H., Bailey, E. Z. 1976. Hortus third. Revised. MacMillan, New York, N.Y., USA. 1290 pp.
  • Scoggan, H. J. 1978, 1979. The flora of Canada. Nat. Mus. Nat. Sci. (Ottawa) Publ. Bot. 7(1)-7(4). 1711 pp.
  • Van Wijk, H. L. 1911. A dictionary of plant names. Martinus Nijhoff, The Hague, The Netherlands. 1444 pp.
  • Victorin, M. 1964. Flore Laurentienne. 2nd ed. Univ. Montreal, Montreal, Que., Canada. 952 pp.

Geographic Information

  • British Columbia

References:

  • Bailey, L. H., Bailey, E. Z. 1976. Hortus third. Revised. MacMillan, New York, N.Y., USA. 1290 pp.
  • Boivin, B. 1966, 1967. Énumération des plantes du Canada. Provencheria 6. Nat. Can. (Que.) 93: 253-274; 371-437; 583-646; 989-1063. 94: 131-157; 471-528; 625-655.

Image or illustration

Images: western water-hemlock - Google Search

Notes on Poisonous plant parts:

The toxins are concentrated in the chambered rootstock but also occur in the leaves and stems as well (James and Ralphs 1986).

Toxic parts:

  • leaves
  • roots
  • young shoots

References:

  • James, L. F., Ralphs, M. H. 1986. Water hemlock. Utah. Sci., 47(2): 67-69.

Notes on Toxic plant chemicals:

Cicutoxin is a highly unsaturated alcohol that is very toxic. The following dosages have been found:

Lethal dose (fresh green plant material) Animal
0.1 kg sheep
0.4 kg cattle
0.3 kg horse

Pigs appear to be more resistant to poisoning than other livestock. Adult humans can be poisoned and can die with only two or three bites of the rootstock (Starrveld and Hope 1975, James and Ralphs 1986).

Toxic plant chemicals:

  • cicutoxin

References:

  • James, L. F., Ralphs, M. H. 1986. Water hemlock. Utah. Sci., 47(2): 67-69.
  • Starreveld, E., Hope, C. E. 1975. Cicutoxin poisoning (water hemlock). Neurology, 25: 730-734.

Animals/Human Poisoning:

Note: When an animal is listed without additional information, the literature (as of 1993) contained no detailed explanation.

Cattle

General symptoms of poisoning:

Notes on poisoning:

Symptoms of poisoning are similar to all classes of livestock. See the information in general notes under Cicuta maculata.

References:

  • James, L. F., Ralphs, M. H. 1986. Water hemlock. Utah. Sci., 47(2): 67-69.

Horses

General symptoms of poisoning:

References:

  • James, L. F., Ralphs, M. H. 1986. Water hemlock. Utah. Sci., 47(2): 67-69.

Humans

General symptoms of poisoning:

Notes on poisoning:

Toxicity and death in humans is possible with all three species of the genus Cicuta (water-hemlock). See the information in the general notes under Cicuta maculata.

References:

  • Starreveld, E., Hope, C. E. 1975. Cicutoxin poisoning (water hemlock). Neurology, 25: 730-734.

Sheep

General symptoms of poisoning:

References:

  • James, L. F., Ralphs, M. H. 1986. Water hemlock. Utah. Sci., 47(2): 67-69.
  • Panter, K. E., Keeler, R. F., Baker, D. C. 1988. Toxicoses in livestock from the hemlocks (Conium and Cicuta spp.). J. Anim. Sci., 66: 2407-2413.

Swine

General symptoms of poisoning:

References:

  • James, L. F., Ralphs, M. H. 1986. Water hemlock. Utah. Sci., 47(2): 67-69.

Another search?