PLANTS POISONOUS TO STOCK. 



237 



Specimens of the three following species of Astragalus have heen for- 

 warded to the Division of Botany with the information that they were 

 causing great financial loss in the districts noted. It is quite prohable 

 that other species are dangerous also. 



POISONING BY WHITE LOCO WEED (AEAGAFAUS SPICATUS). 



This is an erect tufted perennial, 4 to 18 inches high, with pinnately 



CD c 



Fig. 91. — Stemless loco weed 

 {Arai/riUiis lamhertii). u, 

 Flowering plant; h, seed 

 pods ; c, cross-section of 

 seed pod— all one -third 

 natural size. 



1 -xaVa:.. 









•A &mk Hid 



Fig. 9-i. — Woolly loco weed (Astragalus 

 iiiollissimus). It, Whole plant ; h, sec- 

 tion of pod — both one -third natural 

 size. 



divided leaves and spikes of white or cream-coloured flowers, shaped like 

 those of the pea. The pod is one-celled, and when shaken produces a 

 rattling sound, which gives the plant the name of " rattle weed '' m some 

 localities The white loco weed is exceedingly common throughout Mon- 

 tana It occurs most abundantly on the northern slopes of foothdls up 

 to an altitude of about 8,000 feet. Its preferred habitat is for the most 



