SOIL SESSION. 



139 



We have selected these two experiments on corn not because they 

 show the most striking profits, but because they show the necessity of 

 using the right things, at the right time, in the right amounts, and in 

 the right forms. Both bone and blood are excellent forms of plant food 

 for some purposes. But bone acts too slowly for corn, and the high 

 expense of the blood is not justified by the corn crop. The corn could 

 not utilize the slowly available bone in its short growing season. The 

 com needed something more than bone and blood, as shown by the great 

 increase when the potash was added. The potash cost $3.00 per acre 

 and increased the yield 20 and 23 bushels, and converted a loss on the 

 blood and bone into a gain of 25 per cent on the cost of the whole fer- 

 tilizer, and a gain of 360 per cent on the cost of the potash. 



The amount of fertilizer used in these corn experiments was too 

 large, the phosphoric acid was not in the right form, and in plat 2 the 

 most important ingredient is lacking. 



On plat 3, doubtless, even better results would have been obtained 

 had the phosphoric acid been in a more available form. 



A striking thing about the corn from Marionville is that the corn 

 from plat i, unfertilized, has been practically destroyed by the insects 

 that bore through the kernels, that form plat 2, partially fertilized, has 

 been attacked some and that from plat 3, fully fertilized, shows very 

 little damage from the insects. The corn from the three plats has been 

 kept in the same box since harvest. 



EXPERIMENT AT RAYMONDVILLE. MO. 

 Yield from Plot No. 3. Blood, Bone and Potash Fertilizer Applied. 



