158 



SOILS AND FERTILIZERS 



of this form of nitrogen to start plant growth early in the 

 spring. 



204. Crops markedly benefited by nitrates. — Winter 

 grain is usually benefited by an application of 25 to 50 

 pounds to the acre of nitrate of soda about the time that 

 growth begins in the spring. The phosphoric acid and potash 

 fertilizers may be applied in the fall. 



Timothy meadow responds wonderfully to a top dressing 

 of nitrate when the plants first show signs of life. Not only 

 is the yield of hay increased, but the sod is thickened, which 

 increases its value as a manure for succeeding crops. Phos- 

 phoric acid and potash fertilizers should be applied at the 

 same time. The following table shows the increased yield 

 of hay and succeeding grain crops obtained from applications 

 of nitrate fertilizer applied only to the grass crops. Note 

 the increased yield of hay and grain from larger applications 

 of nitrate when the other fertilizers are not increased, and 

 also the striking effect of the better sod on the yield of corn, 

 which crop was not fertilized. This offers a rational method 

 for producing organic manure from mineral fertilizers. 



Table 34. — Yields op Hay and Grain on Unfertilized Soil 

 and on Soil Fertilized for Hay but not for Grain 



