xiv PREFACE 



is a particular pleasure to acknowledge my obligations 

 to Walter T. Swingle of the Bureau of Plant Industry, 

 who has had general charge of experimental date 

 work in the United States; to Thomas H. Kearney, 

 whose study of Tunisian dates is the best work of 

 the kind that we have; to David Fairchild of the 

 same Bureau, to whom is due credit for the intro- 

 duction of several hundred old world varieties of 

 dates into the United States; to Silas C. Mason and 

 Bruce Drummond, both engaged in date research 

 work for the Bureau; to Dr. A. E. Vinson and other 

 members of the staff of the University of Arizona; 

 to Dr. L. Trabut, botanist to the government of 

 Algeria; and to my brother, F. W. Popenoe, now 

 of the Bureau of Plant Industry, who accompanied 

 me during much of my travel and gave me invalu- 

 able help in many ways. 



I have found American consuls in all parts of the 

 world anxious to be of assistance, but none has 

 exerted himself so much on my behalf as Homer 

 Brett, United States consul at Masqat, Oman. Being 

 informed of the date of my coming, he secured from 

 the Sultan of Oman a dozen of his own camels, had 

 the caravan ready for immediate start upon my 

 arrival, and shared with me the hardship, danger, 

 and interest of the one hundred and twenty-five-mile 

 ride to Samail Valley, which had never before been 

 seen by a student of the date industry, although it is 

 the home of one of the most important commercial 

 varieties, the Fardh. Our trip ended rather sensation- 

 ally, involving the kingdom in a year of civil war, but 

 it also resulted in the introduction to California of 

 a number of varieties earlier in ripening than any- 

 thing which had theretofore been known. 



