RATTLEWEED. LOCOWEED (Astrdgalus leucopsis, Torr.). 

 Of the 1,000 species of Astragalus in the world, 35 or 40 occur 

 on the Pacific Coast. They are mostly perennial herbs with 

 odd pinnate leaves, the leaflets very numerous. The usually 

 small, narrow flowers are borne chiefly in spikes or racemes on 

 long peduncles, arising from the axils of the leaves. The seed- 

 pods are often noticeably inflated like bladders. 



Astragalus leucopsis bears pods of this sort, and is further 

 distinguished by greenish-white flowers, and pale leaves with 

 10 to 15 pairs of oval or oblong leaflets each | inch long or so. 

 It blooms from March till May, and is very coma on in South- 

 ern California in the unbroken soil of mesas and plains. 



The term Locoweed, applied to this species and many 

 others, is given because animals that feed on the herbage have 

 a tendency to become insane or loco in Spanish parlance. 

 Doctor Hall, in his valuable handbook "A Yosemite Flora," 

 states that the deleterious effect has been found to be due not 

 to the plant itself but to the presence of the metal barium, which 

 the plant gathers from the soil. This varies in different locali- 

 ties; hence the wide difference of opinion as to the danger from 

 locoweeds. 



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