132 HATCH EXPERIMENT STATION. [Jan. 



due in very large measure to the potash employed, but the 

 dissolved bone-black is also evidently useful. 



The Effect of the .Potash. — It will be noticed that wherever 

 potash is applied, Avhether alone or in combination with 

 either one or both of the other fertilizers, the result is a 

 large yield. Potash is evidently the dominant plant food 

 element on this soil for corn. The increase where this ele- 

 ment is used alone is at the rate of more than 37 bushels to 

 the acre ; the average increase, at the rate of 44 bushels to 

 the acre. The potash used costs at the rate of $3.20 per 

 acre. This amount is covered many times over by the in- 

 crease in the crop. 



The Effect of the Manure. — The manure alone gives a 

 large crop, — considerably larger than on any other plot. 

 That this should be true is natural, in view of the fact that 

 the manure at the rate at which it is applied furnishes a 

 larger amount of plant food than is furnished in the fertil- 

 izers. It also tends to keep up the supply of humus in the 

 soil, and this, as is well understood, is highly beneficial in 

 many ways. The yearly cost of the manm'e applied is, 

 however, at the rate of about $25 per acre, while the com- 

 plete fertilizer used on plot 14 costs only $10. 



The results Avith corn this year are entirely similar in 

 kind to those which have been obtained in the earlier years 

 in which corn has been grown on this piece of land. They 

 show very conclusively that on such land corn can be cheaply 

 grown by the use of fertilizers alone, and they demonstrate 

 conclusively that potash should be a very prominent con- 

 stituent. In view of the fact that the fertilizers generally 

 used by the farmers of the State for corn usually contain far 

 more phosphoric acid than potash, these results appear to 

 be well worth attention. The important question naturally 

 at once arises, "How far are the requirements of the corn 

 crop on the farms in other parts of the State similar to those 

 shown by these experiments?" In answer to this question, 

 attention is called to the results of similar experiments in 

 various parts of the State, which have been published in 

 Bulletins Nos. 9 and 14 of this station. These results indi- 

 cate that in most localities the potash in fertilizers appears 



