General poisoning notes:

Prickly lettuce (Lactuca scariola) is a naturalized herb found across parts of southern Canada. In the western United States, cattle developed pulmonary emphysema after ingesting the plant. The injury appears to be associated with a deficiency, because the toxicity develops after the cattle have fed on dry rangelands. When they are subsequently moved to lush, autumn pasture, some cattle feed ravenously on the prickly lettuce regrowth and, in a few days, the symptoms may develop (Beath et al. 1953).

References:

Beath, O. A., Gilbert, C. S., Eppson, H. F., Rosenfeld, I. 1953. Poisonous plants and livestock poisoning. Wyo. Agric. Exp. Stn. Bull., 324. 94 pp.

Nomenclature:

Scientific Name: Lactuca scariola L.

Vernacular name(s): prickly lettuce

Scientific family name: Compositae

Vernacular family name: composite

Go to ITIS*^ca for more taxonomic information on: Lactuca scariola

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

Manitoba
New Brunswick
Nova Scotia
Ontario
Prince Edward Island
Quebec

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

prickly lettuce:

Images: images.google.com

Notes on Poisonous plant parts:

Mature plants and dried plant material are reported to be harmless. Regrowth of the plants in autumn has caused poisoning in field cases in the western rangelands of the United States (Beath et al. 1953).

Toxic parts:

young shoots

References:

Beath, O. A., Gilbert, C. S., Eppson, H. F., Rosenfeld, I. 1953. Poisonous plants and livestock poisoning. Wyo. Agric. Exp. Stn. Bull., 324. 94 pp.

Toxic plant chemicals:

unknown chemical

References:

Beath, O. A., Gilbert, C. S., Eppson, H. F., Rosenfeld, I. 1953. Poisonous plants and livestock poisoning. Wyo. Agric. Exp. Stn. Bull., 324. 94 pp.

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:

breathing, labored
emphysema
weakness

Notes on poisoning:

Symptoms include pulmonary emphysema, characterized by weakness and difficult breathing. Postmortem examination shows the lung tissue inflamed, with almost complete destruction of the air-cell tissue (Beath et al. 1953).

References:

Beath, O. A., Gilbert, C. S., Eppson, H. F., Rosenfeld, I. 1953. Poisonous plants and livestock poisoning. Wyo. Agric. Exp. Stn. Bull., 324. 94 pp.