The Prairie Thermopsis, Thermopsis rhombifolia Richards, is often eaten by sheep and has in some cases been thought to have poisoned them. The seeds are supposed to be the poisonous part, and several reports have come from western Canada of children being poisoned by eating them. They rarely cause death.

The plant is an erect perennial resembling the Lupines to some extent. It is covered with silky hairs and grows from Manitoba and Kansas to the mountains. The leaves have broad stipules and three obovate leaflets. The short racemes bear a few yellow flowers and recurved pods.

The Scotch Broom, Cytisus scoparius (L.) Link., has been introduced and is found along the Atlantic and Pacific coasts. It contains cytisin, and sometimes poisons stock, causing salivation, vomiting, staggering and paralysis. The lower leaves are compound, with three obo-vate, spiny-tipped leaflets, while the upper ones are sessile and often entire. The yellow flowers are borne in long, leafy racemes.

The Black Locust, Robinia Pseudo-Acacia L., is a tree common in cultivation, the leaves, bark, roots and seeds of which are poisonous, containing an albuminous substance resembling belladonna in its action. Cases of poisoning are comparatively rare, though they have been reported for animals and for people as well. In one case thirty-two boys were poisoned by eating the bark stripped from fence posts. No deaths occurred however.

In cases of human poisoning fever is followed by paleness and coldness of the extremities. There is vomiting. The pupil is dilated and the heart-beat weak and intermittent. The treatment which was administered in the case of the boys mentioned above consisted of "sinapisms over the stomach, sub-carbonate of bismuth, camphor and brandy." (Pammel).

The Clammy Locust, Robinia viscosa Vent., has similar poisonous properties. It is a small tree with glandular twigs, petioles and peduncles. The leaves have more leaflets than those of the Black Locust, varying from eleven to twenty-five. The flowers are pinkish and odourless, in dense racemes.

Fig. 34.   Clammy Locust

Fig. 34. - Clammy Locust - Robinia viscosa.