P R E F A C E . 



The following bulletin by Mr. Walter T. Swingle on the date palm 

 embodies the results of an investigation of the climatic, soil, and cul- 

 tural needs of this fruit tree, which he has had the opportunity to 

 stud} 7 both in the Sahara Desert and in our own Southwest. 



It is shown that no heat is too great and no air too dry for this 

 remarkable plant, which is actually favored by a rainless climate and 

 by hot desert winds. It is also shown that the date palm can withstand 

 great quantities of alkalTTn the soil more than any other useful plant. 

 This demonstration is of special interest now that water has been 

 brought into the Salton Basin, or Colorado Desert, in southeastern 

 California, rendering it possible to irrigate some hundreds of square 

 miles of very rich land where the climate is probably even more 

 favorable for the culture of the choicest sorts of dates than in the 

 Sahara. Recent researches of the Bureau of Soils have shown that 

 a large proportion over half of the soils in the irrigable part of the 

 Salton Basin is too alkaline to support any ordinary crop. It is shown 

 in this bulletin that the date palm can be grown without difficulty on 

 four-fifths of the irrigable lands of this basin, and that on fully one- 

 quarter of the area it is probably the only profitable crop plant that 

 can succeed permanently. It will take considerable time, however, to 

 bring the industry to a paying basis. 



The date palm will be of prime importance in many other irrigated 

 desert areas in the Southwest, where the alkalinity of the soil is too 

 great to permit the culture of other crop plants. It is, moreover, 

 confidently believed that date culture, far from being a last resort for 

 lands unfit for anything else, is one of the most profitable fruit indus- 

 tries, and that it will pay to plant date palms on the best lands and give 

 them the most careful attention. 



The conditions for the proper utilization of the date palm in this 

 country have been determined by means of a very careful study into 

 its life history requirements. This bulletin will show clearly the 

 importance of life history investigations, of which Mr. Swingle is in 

 charge. Such investigations are being extended to other important 

 crop plants. 



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