72 BOARD OF AGRICULTURE. [Jan., 



Gilbert to that tap root, as being the provision by which 

 water is supplied to the plant, while its other roots are 

 occupied with feeding the plant. His remark was, " Yes, 

 and also for supplying nitrogen to the plant; and that," says 

 he, "is the explanation of the fact that the corn plant, under 

 some circumstances, is a renovating plant, and can be grown 

 without rotation for a long period." 



If these things are true which I am stating to you (and I 

 think I have stated them so clearly that you can see where ' 

 fact ends and inference commences), in our manuring for 

 corn, the object must be to put the fertilizers in that region 

 which is occupied by these roots ; in other words, in the 

 region of high temperature. There has been a far different 

 season in New York this year from that which you have had 

 in Massachusetts. It was the coolest summer I have ever 

 experienced during my life. There was but one e\^ening dur- 

 ing the summer when it was comfortable for me to sit on 

 the piazza without an overcoat. Every night but one I slept 

 under blankets, and the thermometer showed a low maxi- 

 mum temperature of the soil during the season of the growth 

 of the summer plants. Under these circumstances, these 

 feeding or upper roots which I have described passed but 

 four inches into the soil. In other words, my corn plants 

 this year fed upon the upper surface of the soil ; and as 

 nearly as we could estimate the relation of the upper roots 

 to these lower roots, it was about as one thousand to one. 



Mr. Sedgwick. Did you see any difference between the 

 plats where the fertilizers were applied and those where none 

 were applied? 



Dr. Sturtevant. The question was as to the influence of 

 cultivation, and the relation of cultivation to the amount of 

 fertilizers applied. My remarks had no reference to the 

 influence of fertilizers. 



Mr. Sedgwick. Was there any difference in that respect ? 



Dr. Sturtevant. I do not want to talk upon that subject, 

 but if it is pressed upon me, I have no secrets. The fact is, 

 that you could trace the influence of the fertilizers in a direct 



