ROOT AND VEGETABLE CROPS 217 



Onions may be regarded as fairly tolerant of alkali, 

 at least in the form of sodium carbonate and nitrates. 

 They were observed (2) making a good growth in a soil 

 containing 4500 to 5700 parts per million of total salts, 

 a large part of which was calcium nitrate. With white 

 alkali, Kearney (17) places the limit as between 4000 and 

 6000 parts per million. Shutt (26) found them growing 

 well in a sandy loam soil containing 1080 parts per million 

 of total salts of which 530 parts per million was sodium 

 carbonate in the upper six inches, the soil to a depth of 

 5 feet containing 1800 parts per million total salts of which 

 1350 parts per million was sodium carbonate. The highest 

 quantity observed by Hilgard (13) was 2405 parts per 

 million of total salts. 



Asparagus is said by Kearney (17) to do well in soil 

 containing as high as 6000 parts per million of white alkali 

 and to be benefited by sodium chloride when in small 

 quantities. 



Celery will grow practically unaffected where the total 

 salt in the soil does not amount to more than about 4000 

 parts per million and is said to withstand sodium chloride 

 very well. 



Radishes were found by Loughridge (19) to be unaffected 

 by 3930 parts per million of total salts, 550 parts per mil- 

 lion of sodium carbonate, or 3240 parts per million of sodium 

 sulphate. 



Other vegetables have not been found to withstand alkali 

 in large quantities. Sodium chloride seems particularly 

 injurious to vegetables such as radishes, carrots, parsnips, 

 and artichokes, the quality being very poor. The seeds 

 of most of the vegetables are small and the seedlings 

 delicate so that vegetable growing on alkali land is very 

 hazardous. 



