General poisoning notes:

Bog-laurel (Kalmia polifolia) is a native shrub found across Canada in boggy areas. The plant has caused experimental poisoning in cattle, goats, and sheep, with sheep being most susceptible. Suspected poisoning of cattle and sheep in the west have been reported. Bog-laurel is less toxic than sheep-laurel (Kalmia angustifolia). Only the western variety of bog-laurel (Kalmia polifolia var. microphylla) has been tested for toxicity. However, the plant should be considered potentially toxic through its entire range in Canada (Clawson 1933, Kingsbury 1964, Lampe and McCann 1985).

References:

Clawson, A. B. 1933. Alpine kalmia (Kalmia microphylla) as a stock-poisoning plant. U. S. Dep. Agric. Tech. Bull., 391. 10 pp.

Kingsbury, J. M. 1964. Poisonous plants of the United States and Canada. Prentice-Hall Inc., Englewood Cliffs, N.J., USA. 626 pp.

Lampe, K. F., McCann, M. A. 1985. AMA Handbook of poisonous and injurious plants. American Medical Assoc. Chicago, Ill., USA. 432 pp.

Nomenclature:

Scientific Name: Kalmia polifolia Wang

Vernacular name(s): bog-laurel

Scientific family name: Ericaceae

Vernacular family name: heath

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

Alberta
British Columbia
Labrador
Manitoba
New Brunswick
Newfoundland
Northwest Territories
Nova Scotia
Ontario
Prince Edward Island
Quebec
Saskatchewan
Yukon Territory

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.

Notes on Poisonous plant parts:

All parts of the plant are poisonous including the nectar, which can result in poisonous honey. The leaves have been used in experiments to poison livestock (Clawson 1933, Fuller and McClintock 1986).

Toxic parts:

all parts
leaves
stems

References:

Clawson, A. B. 1933. Alpine kalmia (Kalmia microphylla) as a stock-poisoning plant. U. S. Dep. Agric. Tech. Bull., 391. 10 pp.

Fuller, T. C., McClintock, E. 1986. Poisonous plants of California. Univ. California Press, Berkeley, Calif., USA. 432 pp.

Notes on Toxic plant chemicals:

Andromedotoxins (grayanotoxins) are resins derived from diterpenes. Several have been found in many members of the heath family and are toxic if sufficient vegetation is eaten (Kakisawa et al. 1965, Fuller and McClintock 1986).

References:

Clawson, A. B. 1933. Alpine kalmia (Kalmia microphylla) as a stock-poisoning plant. U. S. Dep. Agric. Tech. Bull., 391. 10 pp.

Fuller, T. C., McClintock, E. 1986. Poisonous plants of California. Univ. California Press, Berkeley, Calif., USA. 432 pp.

Kakisawa, H., Kozima, T., Yanai, M., Nakanishi, K. 1965. Stereochemistry of grayanotoxins. Tetrahedron, 21: 3091-3104.

Animals/Human Poisoning:

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

Cattle

Goats

General symptoms of poisoning:

depression
nausea
salivation
vomiting

Notes on poisoning:

Experimental poisoning of sheep caused such symptoms as depression, salivation, loss of appetite, and vomiting. Grating of teeth and frequent vomiting was noticed in more severe cases. Pulse and body temperature was affected very little. A dosage of green leaves equal to 0.3% of an animal''s body weight can cause a toxic response. A dosage of 2% of an animal''s body weight caused severe sickness in sheep (Clawson 1933).

References:

Clawson, A. B. 1933. Alpine kalmia (Kalmia microphylla) as a stock-poisoning plant. U. S. Dep. Agric. Tech. Bull., 391. 10 pp.

Kingsbury, J. M. 1964. Poisonous plants of the United States and Canada. Prentice-Hall Inc., Englewood Cliffs, N.J., USA. 626 pp.

Sheep

General symptoms of poisoning:

depression
gait, staggering
nausea
recumbency
salivation
vomiting

Notes on poisoning:

Experimental poisoning of sheep caused such symptoms as depression, salivation, loss of appetite, and vomiting. Grating of teeth and frequent vomiting was noticed in more severe cases. Pulse and body temperature was affected very little. A dosage of green leaves equal to 0.3% of an animal''s body weight can cause a toxic response. A dosage of 2% of an animal''s body weight caused severe sickness in sheep (Clawson 1933).

References:

Clawson, A. B. 1933. Alpine kalmia (Kalmia microphylla) as a stock-poisoning plant. U. S. Dep. Agric. Tech. Bull., 391. 10 pp.

Kingsbury, J. M. 1964. Poisonous plants of the United States and Canada. Prentice-Hall Inc., Englewood Cliffs, N.J., USA. 626 pp.

Information Source: ©Canadian Poisonous Plants Information System, Canadian Biodiversity Information Facility.