56 PASTURE AND RANGE. 



aluminium sulphate, similar to that used for Zygadenus 

 poisoning, forms a chemical antidote, neutralizing the 

 poison not already absorbed. 



BUTTERCUP FAMILY Ranunculaceae. 

 LARKSPUES Delphinium spp. 



The poisonous effects of European Larkspurs have 

 been known for centuries. One species, D. Staphisagria 



v L., called Stavesacre, was used as a poison 



Examples and 



Conditions of ^ or ^ lce - Many species are common in the 

 Poisoning west of Canada and the United States, and 



have occasioned great losses among cattle 

 on the ranges. Marsh and Clawson place them next to 

 the "loco" weeds in the number of animals killed, and 

 Glover, in 1906, estimated the annual monetary loss, in 

 Colorado alone, at $40,000. All parts of the plants are 

 poisonous, the seeds most of all. Leaves and roots are 

 most harmful in early spring. The effects gradually de- 

 crease until after flowering, when practically all of the 

 alkaloids seem to collect in the seed and the rest of the 

 plant becomes harmless. 



Stockmen have blamed the Larkspur for a large part 

 of their losses in both cattle and sheep, and until a few 

 years ago this opinion was entertained even by those who 

 should have scientifically investigated the matter. In 

 1916, however, Marsh and Clawson published an account 

 of experimental work which led them to believe that sheep 

 can withstand the poison, probably on account of its 

 prompt excretion by their kidneys- In repeated instances 

 sheep were fed large quantities of the plants and in no 

 case was any injury produced. They found horses to be 

 susceptible to the poison, though they do not voluntarily 



