The native gardens are situated in the date palm groves and the 

 vegetables and fruit are grown in the partial shade cast by these trees. 

 The natives not only have the question of very saline irrigation waters 

 to contend with, but the soils originally are often very alkaline. In 

 three years they reclaim land too salty to grow the minor crops, using 

 the saline water for that purpose, following the same plan of drainage 

 and weekly irrigation as where crops are growing. One garden situated 

 on the side of a salt flat and originally very saline was visited. Here 

 alfalfa was in very good condition, and fig, pomegranate, melon, tomato, 

 cabbage, pepper, and other plants were growing luxuriantly. The 

 reclamation of this plot by irrigation twice a week had taken three 

 years. 



The native gardeners exercise great judgment in adapting their crops 

 to the soil conditions. Where most alkaline the date palm alone is 

 found ; in other parts of the grove are grown the fig and pomegranate, 

 and in other parts the vegetables less resistant to alkali. The amount 

 of salt in the soil sufficient to injure the palm was not determined, but 

 the French were unsuccessful in an attempt to establish a grove, the 

 water used in irrigation being taken from a salt pond and containing, 

 according to field determinations, 3 parts sodium carbonate, 5 parts 

 sodium bicarbonate, and 1,036 parts sodium chloride in 100,000 parts. 



The irrigation water is all drawn from artesian wells. A number of 

 samples were sent in to the laboratory for analysis, the results of which 

 are shown in the following table. These are fair average samples of the 

 irrigation waters in use, and do not represent by any means the maximum 

 of salinity. Field tests showed as high as 816 parts to 100,000 water 

 in actual use on soils growing vegetables. 



Chemical analyses of artesian water used in irrigating gardens in Sahara Oases, 



Algeria. 



