The lupines are known under a variety of names, the most familiar being wild peas, wild beans, blue pea, blue bean, old-maid's bonnets, Quaker-bonnets, and sundial.
Most of the lupines are perennial plants, growing from one to two feet high. The leaves are palmately compound, that is with the leaflets all attached at the end of the leafstalk and outspread. The leaflets vary in number, according to the species, from five to eleven. They also vary in regard to smoothness and hairiness. The flowers are arranged in an elongated spike or raceme. Many of the species are very showy and well worthy of cultivation as ornamental plants. The colour ranges from pink or cream through various shades of violet to rich blues and purples. Each flower is about half an inch long, and there may be any number from fifteen to fifty or more on a single stalk. The seed pod is flattened usually, showing the form of the seed within.
With the exception of L. perennis L. in Ontario, the lupines in Canada are found on the prairies of Saskatchewan and Alberta and on the hillsides and mountains of British Columbia.
It was found by Sollman that several poisonous alkaloids were present in the American species of lupine. It is thought probable that most, if not all, of the poisoning of live stock was due to these alkaloids, among which was lupinidine, and not to ictrogen, the cause of "lupinosis" in northern Europe. Marsh and Clawson in their experiments also found the alkaloids to be the cause of trouble. They refer to the work of Knowles, who records lupine poisoning among horses, as the "first to note and record definitely cases which can be diagnosed as instances of "lupinosis" or ictrogenic poisoning. The clear-cut evidence presented by Dr. Knowles seems conclusive and makes it probable that other similar cases will be found, although it does not seem likely that lupine causes large losses of horses."
All parts of the lupines above ground are more or less poisonous. The seeds are the most toxic, the pods next, and then the leaves. As the poison is not cumulative fairly large quantities of the plant may be eaten. without harm, provided the toxic limit is not reached at any one time As the toxic dose is a fairly large one, well-fed animals are not likely to suffer.
It seems that no domestic animals are immune to the poisonous lupine, but the greatest losses are among sheep.
Photo - F. Fyles.
Marsh and Clawson found that the general symptoms of poisoning by American lupines were distinctly those of alkaloidal poisoning and not of ictrogenic poisoning. The symptoms of poisoning in sheep are heavy and laboured breathing, sometimes frothing at the mouth, a period of coma with snoring. If able to stand, the animal may fall over in its sleep. In acute cases the animal throws itself about violently in its attempts to breathe, followed by violent trembling, convulsions and death. In other cases the coma deepens until the animal dies without a struggle, although the convulsive attacks are the more usual. In the early stages there is drooping of the ears and pushing of the head against surrounding objects. Sheep affected on the range run about in a frenzied manner, butting into other animals and objects. When attempts were made to give remedies, it was found the animals lost more by the increased excitement. In some cases the first symptoms appeared in one or two hours after feeding, in others not till nearly twenty four hours. Death may follow very rapidly or not for a period of two or three days.
Remedy and Means of Control: Remedial measures are practically of no use for range animals, but as the lupines are most poisonous when in seed it is possible to manage the flock so as to avoid poisoning.
Seed production should be prevented at any cost. This is best done while the plants are in their first bloom, or even before the opening of the flowers. Continued close cutting will in time kill the roots. In some places the land should be cultivated, where possible, and resown with good fodder plants and grasses.