No. 4.] FIELD CROPS. 321 



fast as made and spread during the winter. The land is re- 

 ploughed in the spring, and the most of the fertilizers, mixed 

 just before spreading, are put on broadcast and harrowed 

 in. In the ease of the crop just alluded to, the nitrate of 

 soda, one-half of the superphosphate and one-half of the 

 potash were mixed and put in the drill, being dropped by 

 the same machine which planted the corn, and my practice 

 has usually been similar. 



As most of you are aware, I have during the last few 

 years tried many experiments with a view to getting light 

 as to the manurial and fertilizer requirements of corn. The 

 details of these experiments and the full discussion of the 

 results may be found in the published reports and bulletins 

 of the Hatch Experiment Station. I shall not take your 

 time to present them on this occasion. Suffice it to say 

 that these experiments, which have been in a large measure 

 confirmed by others, indicate the following conclusions : — 



1. It is usually unnecessary to supply a large amount 

 of available nitrogen for the corn crop, and this is explained 

 by the fact that, growing as it does chiefly after considerable 

 warm weather, it can depend largely upon the nitrogen of 

 the organic matter of the soil which becomes available 

 under the influence of natural agencies during the summer. 



2. The corn crop does not make a heavy draft upon the 

 phosphoric acid of the soil, and it is not economy to apply 

 this element largely. 



3. The yield both of grain and stover is largely depend- 

 ent upon the supply of potash. This should be prominent 

 in a fertilizer for this cropland, even if nothing else is 

 employed with manure, it will generally be found profitable 

 to use with it some muriate of potash. 



A crop of 75 bushels of grain and "2\ tons of stover will 

 take from the soil about 121 pounds of nitrogen, 43 pounds 

 of phosphoric acid and <sl pounds of. actual potash ; 1 "> tons 

 of average corn silage will take 100 pounds of nitrogen, 37 

 pounds of phosphoric acid and 118 pounds of potash. It 

 will be noticed that the potash is relatively more and the 

 phosphoric acid less abundant in the silage. This is due to 

 the fact that the proportion of ears in the latter is smaller, 



