20 THE DATE PALM. 



consisting chiefly of sulphates of sodium and magnesium and a 

 little of the chlorides of these metals. These soils also contain 

 a great deal of sulphate of lime, which is believed to counteract 

 the poisonous effects of the magnesium salts, and to prevent the 

 formation of the very injurious black alkali. Swingle states : 

 " If a soil at all depths contains over 0'6 per cent, of alkali, the 

 growth is slower and the yield is less than on better lands, and 

 where the alkali content is everywhere over 1 per cent., date- 

 palms do not bear fruits regularly, and their growth is very slow." 

 These figures exclude salts accumulated on the immediate 

 surface of the soil. Unlike many other plants, the adult 

 date-palm can withstand very large accumulations of alkali on 

 the surface of the ground. In laying out a young date plantation, 

 however, the risks of the plants dying before becoming 

 established will be greater if there is a surface accumulation of 

 these salts. It may not be convenient to have all soils analysed 

 before starting a plantation, but as wheat, corn, and lucerne, 

 crops, peach, orange, prune trees, etc., are all believed to be 

 unable to flourish in 0'6 per cent, of alkali, young date trees 

 may be planted where one or other of the above can grow 

 well. Barley, sorghum, sugar-beets, grape-vines and possibly 

 pomegranates are believed to stand from 0'6 to 1 per cent, 

 of alkali, but unlike well-established date-palms these plants 

 are easily killed by an accumulation of the alkali on the soil 

 surface. 



I recently took 9 samples of soil from the Arabian date 

 plantation in the garden of the Victoria Memorial Hall, Muzaf- 

 fargarh, where crops of barley have regularly been a failure. 

 The Agricultural Chemist, Punjab, kindly analysed the samples 

 for me and the chemical results which he gave have been in- 

 corporated by me in the table on next page. 



