PLANT FEEDING. 



11 



Manures or fertilizers may be so compounded as to 

 furnish the three important elements in any proportion 

 desired. 



Carriers of nitrogen. Nitrate of soda, sulphate of 

 ammonia and dried blood are commercial forms of fer- 

 tilizing materials that supply nitrogen only. The per cent 

 of nitrogen is shown in the following table : 



Material 

 Nitrate of soda, 

 Sulphate of ammonia, 

 Dried blood, 



Per cent Nitrogen 

 16 

 20 

 14 



27. How many pounds of nitrogen in a ton of nitrate 

 of soda? 



Process : 2,000 X -16 = 320 



28. How many pounds of nitrogen in a ton of sul- 

 phate of ammonia ? 



29. How many in a ton of dried blood ? 



30. When you apply 100 pounds of nitrate of soda to 

 an acre of land, how many 



pounds of actual nitrogen are 

 applied ? 

 Process : 100 X -16 = 16 pounds. 



31. How many pounds of 

 actual nitrogen are applied 

 to the soil when a mixture of 

 50 pounds of nitrate of soda 

 and 50 pounds of sulphate of 

 ammonia is used ? 



32. How many pounds of W " H AND WlT "" T FERTILIZE - 



. . , , . , MI 1 Wheat was used here as a soil- 

 dried DlOOd Will be necessary ing crop. The plot at the left 

 , |. made 4.6 tons to the acre, while 

 tO increase tne application tO the one at the right having had 

 Of) rriinr1c? an application of nitrate of soda 

 dU pOUnOS f produced 7& tons. 



