CHAPTER 7 

 LOCO WEEDS AND OTHER POISONOUS PLANTS 



Black Locust (Robinia pseudo-acacia). This is a tall forest tree of 

 eastern North America with a rough bark, pinnately compound leaves. 

 Its papilionaceous flowers are white, sweet-scented and borne in pendulous 

 racemes. Its wood is hard and during the world war, 1914-18, was much 

 sought after to make the wooden pins used in building the emergency 

 fleet of wooden vessels. The bark and leaves of this tree contains a 

 powerful poison which has proved fatal in a number of cases. The bark 

 of this tree contains a toxic albumose and a toxic glucoside, named robitin, 

 which has now been isolated by B . Tasaki and U. Tanaka. In the fresh bark 

 one per cent, of the glucoside is present, and the toxic reaction is caused 

 by a dose of 0.0015 gram in the horse and 0.02 gram in cattle. The reac- 

 tion of robitin when injected into horses is exactly that produced by the 

 fresh bark, and consists in dyspnoea, increase of secretions and excretions 

 and paralysis of the hind quarters. The seeds also are poisonous. 



Symptoms. The symptoms of poisoning are like those produced by 

 belladonna and this is manifested in the cases of several horses that ate 

 the bark off the tree for the animals had colic, tympanites and paralysis. 

 The most prominent case where human beings were poisoned is given by 

 Dr. Z. P. Emery. In March 1887, thirty-two boys inmates of the Brook- 

 lyn Orphan Asylum were poisoned at one time by eating the bark of the 

 tree. The symptoms were the vomiting of a ropy mucus, flushing of the 

 face, dilated pupil, dryness of the throat, feeble pulse, extremities cool, face 

 pale, vomiting of blood, cold extremities, heart feeble and intermittent, 

 face deathly pale with stupor. A rash similar to that of belladonna poi- 

 soning was present, but only temporary. A high-fever was noticed in the 

 beginning. The treatment consisted of sinapisms over the stomach, 

 subcarbonate of bismuth, camphor and brandy. 



Broom(Cytisus (Sarothamnus) scoparius). This European shrub is 

 rather uncommon in America, but on Nantucket, Naushon and elsewhere 

 it has been planted to hold embankments. It has also become adventive 

 on the Pacific coast. The tough, wiry stems are dark green and the leaves 



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