] ] 7 settlers— old and new 



of a century the starling, so overly familiar in eastern cities, 

 has been gradually advancing westward toward the Pacific 

 Coast. Plants also have been moving in both directions for 

 a long time. Few easterners who gather black-eyed susans 

 know that they moved (or more probably were carried 

 unintentionally as seed) from our own West within the 

 period of our national history. Few who plant the giant 

 "Russian" sunflower know that it belongs to an exclusively 

 American genus which was taken to Russia in the nine- 

 teenth century, taught gigantism there, and then returned 

 to us with the benefits of a foreign education. Probably 

 the comrades who munch its seeds would deny its origin 

 at the same time that they claimed credit for its improve- 

 ment. 



In Arizona alone there are some two hundred different 

 plants which are recognized as having been introduced by 

 man — in most cases unintentionally. Some of them arrived 

 as the now dominant population did — westward across the 

 continent from the eastern seaboard. But quite a few 

 others came overland from the Pacific Coast or up from 

 Mexico. And a number of those which moved in from the 

 West are, like the Indian, Asiatic, not European, immi- 

 grants. 



Meanwhile, perhaps an equal number of plants have 

 been deliberately introduced or gone as stowaways from 

 the New World to the Old. Everybody knows about to- 

 bacco, potatoes and Indian corn, but that is merely be- 

 cause they happen to be of great economic importance. 

 Many European weeds came from the Americas and so, of 

 course, do many now familiar European garden flowers, 

 a surprising number of which are horticulturists' develop- 

 ments from California species. 



