206 



THE PLANT WORLT*. 



Figvire 42. Patches of Alfilaria growing at 4,000 feet elevation, near 



Oracle, Arizona. 



region, allilaria enjoys quite a general distribution througliont 

 the warmer parts of both temperate zones. Its introdnctiou in 

 the ]S[ew World is believed generally to date back to the time of 

 the Spanish explorations. 



The introduction and spread of alhhirin in Arizona forms 

 an interesting chapter in the earlier history of our stock ranges. 

 The occurrence of a prolonged drought over southern California, 

 during 18Y0 to 1871, resulted in numerous herds of sheep being 

 driven into Arizona where boundless hills and plains, as yet little 

 grazed, afforded timely relief from thorn in addition to an abun- 

 dance of range for years to come. These animals carried in 

 their fleeces a liberal cpiantity of aliilaria seed from tlie mesas of 

 southern California where the plant had been growing ])lcnti- 

 fully since the memory of the earliest settlers. Two or three 

 years later alfilaria appeared in quantity along certain frontier 

 stage and freight roads over which the sheep had been driven. 



