404 THE MUSTARD CROP. 



that the potash abstracted from the soil is less in amount 

 than seeding crops usually require, the phosphoric acid 

 is shown to be required in large quantities. The large 

 quantity of lime and of sulphuric acid would indicate 

 that manurial applications containing these ingredients 

 gypsum, for instance would be beneficial to the crop 

 when grown for seed purposes. 



