THE 1RRIGA TION AGE 415 



the temperature may fall as low as 16 degrees above zero. Although 

 the date palm requires intense heat in summer, it will withstand in 

 winter a temperature that would be fatal to the fig or the orange. 

 These climatic conditions are practically identical with those that ob- 

 tain in the more southern portions of the Groat Colorado Desert. So 

 great is the similarity, in fact, Mr. Wilson says, that so far as climate 

 is concerned, we may reasonably expect the date palm to fruit satis- 

 factorily in th arid regions of the southwest. The experiments 

 carried on through the Departmentjshow that probably the soil best 

 adapted to the date palm is the one containing a small percentage of 

 clay, fairly free from humus, and charged with alkali. Irrigation and 

 heat are all important conditions. Water is indispensible. The roots 

 should be moist at all times. An old Arabian proverb says that 



"The Date must have its head in fire and its roots in the water." 

 The water used may advantageously be quite warm and contain 

 alkali. Dates may, however, be planted along streams, or by springs 

 -or flood basins, and in such situations will grow well; adding much to 

 the landscape by their graceful pinnate foliage. The future of the 

 date industry in the United States, however, depends upon irrigation, 

 and upon irrigation which will not fail in the dryest seasons. Irriga- 

 tion in the Sahara has greatly increased the date areas of Africa and 

 the conditions are so similar in our own Southwest under artificial 

 watering that the success of the industry there seems assured. 



Varieties of dates are almost innumerable. They differ grea tly 

 in their color, size, sweetness, delicacy of flavor and length of time 

 required to mature. The" dates of commerce are usually light colored, 

 these being better shippers. The male and female flowers of the palm 

 are borne on different plants, the females only bearing the fruit. The 

 blossoming period is a long one, usually about six weeks, but is always 

 late, thus escaping spring frosts. The average yield of a tree is eight 

 bunches, each weighing about 17 pounds, although a bunch may weigh 

 as much as 40 pounds. In Arizona, under irrigation, seedling trees, 

 seven years old, have produced upwards of 200 pounds in a single 

 season. 



