STOCK-POISONING PLANTS OP THE RANGE. 11 



altitudes than Delphinium menziesii and apparently never grows in 

 sufficiently large masses to be dangerous. 



The low larkspurs are poisonous throughout the whole period of 

 their lives, while the tall larkspurs gradually lose their poisonous 

 properties after blossoming. 



In Plate XII is shown a larkspur with white blossoms, Del- 

 phinium virescens, which is quite common in the plains regions east 

 of the Rocky Mountains. This plant probably rarely occurs in suf- 

 ficient abundance to cause harm, but there is reason to think that at 

 some seasons it has occasioned the death of a considerable number of 

 animals. 



PARTS OF LARKSPURS POISONOUS. 



There is a general belief throughout the West that it is the roots of 

 the larkspur which are particularly poisonous. Expemments have 

 proved conclusively, however, that the different parts of the plant are 

 equally poisonous, with the exception that the seeds are especially so. 

 Probably in almost all cases of larkspur poisoning the trouble is caused 

 by eating the leaves, sometimes with the flowers. As was intimated 

 before, most of the cases of larkspur poisoning occur in the spring or 

 early summer. 



ANIMALS POISONED BY THE LARKSPURS. 



While horses can be poisoned by corral feeding of larkspurs, there 

 is reason to think that if left to themselves upon the range they never 

 eat enough of these plants to do any harm. Sheep eat the larkspurs 

 freely without suffering any evil consequences. There is quite a 

 general belief in many regions of the West that losses of sheep have 

 been caused by larkspur feeding, but extensive experiments upon a 

 large number of species, and in different regions, have proved con- 

 clusively that sheep can be grazed upon larkspur without any risk 

 whatever. In fact, it may almost be said that larkspur furnishes 

 good forage for sheep. The losses from larkspur poisoning, then, 

 are altogether with cattle, and these losses are very heavy. 



SYMPTOMS OF LARKSPUR POISONING. 



While the result of corral feeding shows that there are a number of 

 preliminary symptoms, as animals are noticed upon the range the 

 first symptom commonly observed is the sudden falling of the animal, 

 accompanied by violent struggles. The animal is unable to rise, 

 but after a few moments may get upon its feet and walk away, and 

 show no further symptoms. In more acute cases of poisoning the 

 first fall will be followed by a second, and that possibly by a succes- 

 sion of falls, which in severe cases of poisoning are followed by com- 

 plete prostration, vomiting, and death. 



