THE ROTATION OF CROPS 



GENERAL RULES 



A few general rules may be made use of in ar- 

 ranging the order of the crops in the rotation though 

 they cannot always be strictly followed. 



Crops that require the elements of plant food in 

 the same proportion should not follow each other. 



Deep-rooted crops should alternate with shallow- 

 rooted crops. 



Humus makers should alternate with humus 

 wasters. 



Every well arranged rotation should have at least 

 one crop grown for its manurial effect on the soil, 

 as a crop of cowpeas, or one of clover, to be turned 

 under. 



The objection often made to this last rule is that, 

 aside from the increase in fertility, there is no direct 

 return for the time, labor and seed, and the land 

 brings no crop for a year. It is not necessary to 

 use the entire crop for green manuring a part of 

 it may be used for hay or for pasture with little loss 

 of the manurial value of the crop, provided the 

 manure from that part of the crop taken off is re- 

 turned and the part of the crop not removed is 

 turned under. 



LENGTH OF THE ROTATION 



The length of the rotation may vary from a two- 

 course or two crop rotation to one of several courses. 



