CORN 



NECESSITY OF ROTATIONS. If the great wastes and rapid 

 depletion of the soil which follow continuous cropping are to be 

 avoided, it is necessary to adopt some systematic rotation of crops, 

 including some legume. The objects of a rotation are: 



(i) To maintain or improve the physical condition of the sod. 



(2) To conserve or improve the soil fertility. 



(3) To guard against insect pests and noxious weeds. 



(4) To distribute the labor throughout the season. 



(5) To supply more economically the necessary protein to bal- 

 ance the corn ration. 



To accomplish the first two objects it is necessary to check the 

 unnecessary waste of humus and to replace by plowing under crop 





i*":\i^Mt::. 



MOWING A CEOP OF ALFALFA, ONE OF THE LEGUMES WHICH NOT ONLY DEPOSITS NI- 

 TROGEN IN THE SOIL, BUT OPENS UP THE SUBSOIL TO CONSIDEBABLE DEPTH. 



residues that which is gradually lost. This cannot be done by simply 

 alternating corn and oats, or by any rotation which does not include 

 a leguminous crop. 



Different crops occupy different strata of the soil, and make differ- 

 ent demands upon the elements of plant food. The deep-rooted le- 

 gumes utilize plant food which lies beyond the reach of the shallow- 

 rooted cereals, after the former are removed from the soil a large 

 amount of hitherto unavailable plant food is brought within the reach 



