196 Agricultural Chemistry. 



is practically covered by a continuous return of plant food from 

 this crop to the soil. 



The miscellaneous crops, grown chiefly for the truck market, 

 give cash returns which justify the expense of "forcing" rations 

 of plant food. Such rations should include liberal amounts of 

 nitrogen. Tobacco should receive some nitrogen and a liberal 

 supply of potash, with phosphoric acid in moderate amount. Too 

 much nitrogen is to be avoided because of unfavorable effects on 

 the quality of the tobacco leaf. Cotton-seed meal at the rate of 

 200 to 300 pounds per acre before planting is a favorable ration. 

 Potash should be applied as sulphate ( 100 Ibs. ) , as the chloride 

 is injurious. Phosphoric acid should be applied at the rate of 

 200 pounds of acid-phosphate or 400 pounds of bone meal per 

 acre. 



Cabbages, as a market crop, are brought to harvest early and 

 are improved in quality by heavy applications of nitrogen. Nit- 

 rate of soda or sulphate of ammonia at the rate of 300 pounds per 

 acre in two or three top dressings is recommended in addition 

 to general manuring. 



No specific rules can be laid down for the application of fer- 

 tilizers to each crop, because of the greatly variant conditions of 

 soil and climate under which it must be grown. These factors, 

 particularly the latter, exert a profound influence on the growth 

 of plants. Each farmer must determine the requirements of his 

 own conditions by the fertilizer tests described in the chapter 

 on "Fertilizers." 



Factors influencing the composition of the crop are: Stage 

 of growth, exposure at harvest, fertilizers and environment. 



The stage of growth has been shown to present marked differ- 

 ences in the feeding value of the straw of cereal plants. In the 

 true hay crops the grain takes up most of the nutrients of the 

 plant during the ripening period. This results in increased fil 

 content and decreased feeding value of the stems. The Conn* 

 ticut Experiment Station gives the following composition 

 timothy at successive periods preceding ripening. 



