CORN FERTILIZERS 157 



147. Quantity of fertilizer. Until the recent agitation 

 about the Williamson method of corn culture, it was the 

 general opinion that it was ordinarily not advisable to 

 use very large amounts of commercial fertilizer for corn, 

 400 pounds per acre being then considered a rather heavy 

 application for this crop. 



Experience shows that corn does not, as surely as cotton, 

 pay a large profit on a large quantity of commercial fer- 

 tilizer. There is more risk with the corn crop because its 

 bearing season, from silking to hardening of the kernels, is 

 shorter than the fruiting season of cotton; and drought 

 at this critical time in the life of the corn plant is apt to 

 ruin the crop, regardless of the amount of fertilizer em- 

 ployed. 



LABORATORY EXERCISES 



(1) Compare 10 corn plants grown on a rich bottom soil 

 with 10 others of the same variety grown on a dry upland, 

 recording : 



(a) average height of plant ; 



(6) average height of upper ear above ground ; 



(c) average number of square feet of ground occupied by 



each plant, and 



(d) average weight of shucked ear or ears per plant. 



(2) Apply a teaspoonful of nitrate of soda to each corn plant 

 on one row and each week afterwards compare the size and 

 color of plants on this row with those that received no nitrate 

 of soda. 



LITERATURE 



DUGGAR, J. F. (Rotation.) Ala. Expr. Sta., Bui. No. 134. 

 DODSON, W. R. (Rotation.) La. Expr. Sta., Bui. No. 111. 

 WHITNEY, MILTON. (Fertilizers.) U. S. Dept. Agr., Bur. Soils, 

 Bui. No. 64. 



