DATES OF EGYPT AND THE SUDAN. 



Table I. — Meteorological data for stations in the three great climatic zones of Egypt and 

 the Sudan, showing the chai-acteristic date varieties for each type of climate. 





Mean 



relative 



humidity. 



Mean temperature 

 (°F.). 



Heat 



units 



above 



64.4° F., 



May 1 to 



Oct. 31. 





Zone and locality. 



Annual. 



February 



to 

 October. 



Varieties of dates grown. 



Maritime subtropical: 



68 

 74 

 69 

 62 



68.32 

 68.95 

 67.28 

 69.96 



70.36 



70.86 

 70.86 

 73.68 



2,049 

 2,191 

 2,179 

 2,714 





Port Said 



Aglany, Amri, Bint Aischa, 

 } Hayany, Kobi, Samany, 

 | Zagloul. 







Desert subtropical: 



1 Amhat, Hamrawi, Hayany, 





54 



68.90 



72.54 



2,596 







Siut ( Assiut) 



S3 



36 



39 



70.29 

 73.92 



77.30 



74.08 

 78.40 



81.92 



3,147 

 3,675 



4,296 





Dakhleh 



Saidy, Sultany, Tamr, Ham- 

 rawi, Falig. 



Desert tropical: 



Gondeila, "Ibrimi." 

 1 



Wadi Haifa 



34 

 24 

 38 

 33 



77.05 

 81.84 

 81.73 

 82.95 



81.54 

 85.61 

 84.95 

 85.69 



4,160 

 4,708 

 4,454 

 4,396 



1 "Ibrimi," Barakawi, Ben- 





> tamoda, Gondeila, Kosha, 





Kulma. 











THE MARITIME SUBTROPICAL ZONE. 



Of the 22 varieties of dates here listed, 7 are grown only in the 

 delta, or their culture extends but a short distance into Upper Egypt. 

 Of these, 5 varieties are used only in the fresh, or "rutab" (succulent), 

 condition. These are the Bint Aischa, Hayany, Kobi, Samany, and 

 Zagloul. 



The territory represented by these varieties has the three meteoro- 

 logical stations of Alexandria, Port Said, and Gizeh (Table I), which 

 gives almost uniform mean temperatures, the annual means varying 

 less than 2 degrees and the means for the 9 months of the growth of 

 the flower stalk and fruit, February to October, inclusive, being almost 

 uniformly 70° F. 



In explanation of the significance of column 5 of Table I, headed 

 "Heat units above 64.4° F.," the following extracts from pages 63 

 and 65, Bulletin No. 53 of the Bureau of Plant Industry, by Walter 

 T. Swingle, including table 9, from page 66 of the same bulletin, are 

 here given : 



It has been < :i |r-ii ];if ,ed by De Oandolle that temperatures down to 18° C. or 64.4° 

 J', have qo effect or fche flowering or fruiting of the dato palm, and a study of the 

 record sheets of a self-recording thermometer kept at Biskra in the midst of a date 

 Orchard confirmed the correctness of tin's assumption. In other words, this relatively 

 high temperature i- Me- zero point for this plant, so far as flowering and fruiting are 

 concerned, though if is able to grow at somewhat lower temperatures. . . . The 

 table [table 9] give tbe summation of effective temperatures during the fruiting 

 on of the date palm for a number of points in North Airicaand in the Southwestern 

 .States. 



