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ter they are able to withstand a fair amount of .cold ; but for the 

 ripening of the fruit a high temperature is absolutely necessary. 

 Swingle states : 'There is little hope of growing even early sorts 

 unless the mean temperature in the shade goes above 80° F. for at 

 least one month in summer, and the mean temperature of the fruit- 

 ing season, from May to October, is above 70' F. It is, further, 

 fairly certain that during the months when the fruit is developing, 

 viz., May to October, inclusive, the mean temperature must be 

 about 75" F., and during June, July, and August above 80° F., if 

 moderately late varieties of dates are to be brought to maturity. 

 In regions where late varieties of dates come to maturity, the mean 

 temperature for June, July, and August must be 90^ F. or there- 

 abouts. 



Dry atmosphere. — In this case, again, while the date palm grows 

 fairly will in a moist climate, the fruit natures properly only in a 

 dry atmosphere. Consequently, dates are grown most successfully 

 in the hottest and driest regions. 



Water supply. — Although the date delights in a dry, hot climate 

 it requires a constant, though not particularly abundant supply 

 of water at its roots. The subject of irrigatiion is therefore one 

 of primary importance to the date grower. 



PLANTING AND CULTIVATION. 



The Arabs of Mesopotamia plant only suckers ; these are seldom 

 over 6 feet long and generally with few roots. They are planted 

 with the growing bud only 2 or 3 inches above the surface of the 

 soil, and for the first month are watered every four days, and later 

 at longer intervals as the season may demand. 



The French colonists give much more attention to the careful 

 planting of dates. They plant in regular rows, the arrangement 

 depending, as a rule, on some properly conceived system of irri- 

 gation. It is held by them that the palms should be placed at 

 distances of 30 feet, and in intervening spaces are usually oc- 

 cupied by garden crops. 



It is found in the Sahara that one male ti'ee will provide suf- 

 ficient pollen for about 1 00 female trees, and the male and female 

 trees are accordingly planted in this proportion. 



Little has been done in the way of working out the manurial 

 requirements of the date palm. The Arabs use what manure they 

 can obtain from their camels and goats. On the larger plantations 

 it has been found impossible to obtain a sufficiently large supply 

 of farmyard manure. There can be no doubt that a proper system 

 of green manuring, with such leguminous plants as alfalfa, horse 

 bean, cow-pea, and others, would be a great advantage. Neither 

 in Africa nor on the Persian Gulf does any such system appear to 

 be known. 



As suubsidiary crops between the palms, in addition to garden 

 produce, cereals are frequently grown, but the yield is rarely good : 

 grape vines appear also to thrive well and produce good fruit. 

 Many fruit trees, including olives, seem to appreciate the shade 

 afforded by the date palms. 



