3o6 SYSTEMS OF MANURING CROPS [chap. 



extraneous manure, while really high farming for big 

 crops involves a considerable wastage of nitrogen 

 applied to the land and never recovered in the crop. It 

 is only by experience, by the knowledge of his own land 

 and the market conditions which prevail, that the 

 individual farmer can tell how high it is profitable for 

 him to farm, and therefore to what degree he can 

 utilise the information as to feeding his crops which is 

 provided by field experiments. 



The discussion that follows of the manures appropri- 

 ate to each of the staple crops is therefore intended to 

 supply the farmer, not with a series of recipes or patent 

 mixtures that are universally applicable, but with 

 principles out of which he can construct a rational 

 system appropriate to his own farm. In the practice of 

 farming many things may at once be set down as 

 " wrong," but there can be nothing absolutely " right " ; 

 the proper course of action is never anything more than 

 a judicious compromise adapted to all the various con- 

 ditions of climate, soil, and markets. We can now 

 consider the ordinary farm crops separately. 



Wheat in the typical four-course rotation follows 

 the ploughed-up clover ley, and generally derives all 

 the nitrogen it requires from the residues left by the 

 clover in the soil. In many cases, however, oats are 

 now substituted for wheat after the ley, because more 

 time is thus obtained to graze the aftermath and 

 break up the land before seeding; oats also after the 

 ploughed land has been exposed for the winter suffer 

 less than wheat from the wireworm which is apt to be 

 prevalent in the old clover land. Should wheat follow a 

 good crop of clover further manuring is not required ; 

 though if the second growth of the clover has been 

 allowed to ripen seed, which removes a large proportion 

 of the stored up nitrogen, or if much rye grass has been 



