88 



THE DATE PALM. 



Station No. 3, at Chegga, represents a subsoil thrown up in digging a drainage ditch 

 and was so charged with alkali as to have become nearly solid. The soil canie from 

 a depth of 4 to 6 feet, and contains the following amounts of alkali: 



TABLE 22. Per cent of alkali in subsoil of date plantation, station No. 3, Chegga, Algeria. 1 



1 Mr. Seidell's original analysis of the sample from this station is as follows: 



Though less alkaline than the subsoil of sample No. 1, which contained 2. 765 per 

 cent, this still shows a very high salt content. 



When date palms were first planted on this property, many of the offshoots were 

 lost through excessive alkalinity. The digging of drainage ditches has rendered it 

 possible to wash out much of the alkali, even with the very bad water used for 

 irrigation, as' is evidenced by the fact that alfalfa can now grow on some of the land. 



ALKALI CONDITIONS IN RELATION TO DATE CULTURE AT M'RAIER, ALGERIA. 



Going southward from Chegga, the Little Desert of Moran is traversed until a 

 somewhat abrupt descent is reached, which is marked by a series of low cliffs called 

 Kef el Dohr. At the base of this declivity there extends an almost unbroken plain, 

 which slopes gently to the eastward to the shores of the salt lagoon, ChottMelrirh, or 

 rather a branch of it called Chott Merouan (see map, PL II, p. 76). This salt lagoon 

 is often dry, but always contains mud covered with a white crust of salt two-fifths 

 of an inch or more thick. In proceeding southward, the road skirts the edge of the 

 lagoon, and during the heat of the day the most deceptive mirages are seen in look- 

 ing across the Chott (PL XVIII, fig. 2) . 



This region is remarkably like the Salton Basin in many ways, and Chott Melrirh, 

 like Salton Lake, is below sea level, the lowest part or the western border of Chott 

 Melrirh being some 100 feet (31 meters) below sea level. The plain to the west is flat 

 and extremely arid. Occasional small sand dunes occur, which are like those in the 

 Salton Basin. 



The oasis of Ourir, seen in passing, is one of the largest created by the French set- 

 tlers, containing some 40,000 date palms. It is 42 feet (13 meters) below the sea 

 level. 



A stop was made at M'rai'er, an oasis of considerable size (some 60,000 date palms) 

 owned by Arabs. It is from 10 to 12 feet below sea level. In the village of M'rai'er is 

 a very saline area, where the scanty vegetation is composed of stunted saltbushes, sam- 

 phires, etc. The water level was only a few inches below the surface. A stunted date 

 palm grew some 15 feet away from the spot where the soil sample was obtained, but 



The lowest part of Salton Lake is some 270 feet below sea level. 



