FOOD FOR PLANTS 169 



12. The wide range in the proportionate content 

 of nitrogen in the crops, shows clearly that greater 

 care should be exercised in measuring out the nitro- 

 gen to our cultivated crops. 



13. Out of every 100 pounds of nitrogen applied in 

 the form of Nitrate, there were recovered in the first 

 rotation 62.76 pounds, and in the second rotation 

 61.42 pounds. The corresponding returns for ammo- 

 nium sulphate were 49.51 pounds and 37.01 pounds 

 respectively; and for the dried blood 47.89 pounds 

 and 32.05 pounds respectively. This indicated that 

 the acidity in the soils of series 17 and 18 had in- 

 creased sufficiently to interfere with the normal 

 growth of the plants. 



14. Out of every 100 pounds of nitrogen applied 

 in the form of animal manures, there were recovered 

 in the first rotation less than 25 pounds, and in the 

 second rotation less than 30 pounds. 



15. A comparison of the crop yields in the first and 

 second rotation, shows that the animal manures have 

 a marked cumulative effect. 



16. The corn crops seem to have utilized a smaller 

 proportion of the nitrogen applied than was utilized 

 by the oats and wheat. 



17. The fresh manures were utilized better than 

 the leached manures. 



18. The solid and liquid, fresh, was utilized better 

 than the solid, fresh. 



19. The solid and liquid, leached, was utilized bet- 

 ter than the solid, leached. 



20. The smaller applications of Nitrate were util- 

 ized to about the same extent as the larger applica- 

 tions. 



