UNITED STATES DEPARTMENT OF AGRICULTURE 





% BULLETIN No. 947 



Contribution from the Bureau of Animal industry 

 JOHN R. MOHLER, Chief 



S^W'&J'U 



Washington, D. C. 



PROFESSIONAL PAPER 



October 11, 1921 



WESTERN SNEEZEWEED (HELENIUM HOOPESII) 

 AS A POISONOUS PLANT. 



By C. Dwight Marsh, Physiologist in Charge of Investigations of Stock Poisoning 

 by Plants; A. B. Claw son, Physiologist; James F. Couch, Pharmacological 

 Chemist; and Hadleigh Marsh, Veterinary Inspector, Bureau of Animal Industry. 



CONTENTS. 



Page. 



Introduction 1 



Historical summary 1 



Description of the plant 3 



Experimental work 6 



Feeding experiments with sheep 11 



Feeding experiments with cattle 15 



Chemical examination of the plant 17 



Urine examination 23 



Discussion and general conclusions 24 



Symptoms 24 



Autopsy findings 27 



Pathology of H. Iwopesii poisoning 27 



Toxic dose for sheep 30 



Toxic dose for cattle 30 



-'- Acutecases 31 



Page. 

 Discussion, etc. — Continued. 



Toxicity of leaves of plant 32 



Toxicity of flowers 34 



Toxicity of stem leaves 34 



Comparative toxicity of different parts of the 



plant 34 



Effect of drying on toxicity of leaves 35 



Seasonal variation in toxicity of the plant ... 36 



Permanent effect produced by the poison — 37 



Remedies 38 



Treatment of plant on the range 39 



Practical suggestions for stockmen on the 



range 44 



Summary 45 



Literature cited 46 



INTRODUCTION. 



historical summary. 



In 1903, V. K. Chesnut, who was at that time in charge of poisonous- 

 plant investigations in the Department of Agriculture, while visiting 

 Sevier County, Utah, was told that a disease of sheep was prevalent 

 in that part of the State. The disease was characterized by vomiting 

 and wasting away, the sheep dying after a time varying from a week 

 or two to a month. Nothing further was heard of this disease by 

 the department until January, 1914, when the senior author, who 

 was making an address to the stockmen of Salina, LTtah, was told 

 that the sheep on the summer ranges in the Wasatch Mountains 



28468°— 21— Bull. 947 1 



