202 CHEMICAL FERTILIZERS 



after year. Very important points in the consideration of 

 any rotation is the reduction of labour costs and the greater 

 healthiness and productivity of the crops obtained. A 

 rotation allows an economy of labour because it secures the 

 steady work of the labourers at all times of the year, with 

 neither periods of overwork nor times of idleness. The more 

 complex the rotation, and the greater the variety of crops 

 grown, the more nearly can this ideal be attained ; seed time 

 and harvest will extend over much longer periods with many 

 crops than with few, and the ratio of the number of labourers 

 employed to the yield of the crops obtained will be reduced ; 

 risks of heavy fluctuation in price will become lower, since, 

 however bad may be the outlook for one crop, compensa- 

 tion is obtained from some other more successful crop. The 

 needs of the live stock must also be taken into account in 

 fixing the method of farming and the system of manuring 

 applied ; suitable food must be provided for the cattle all 

 the year round, and this ought to be mainly grown on the farm 

 concerned. Of the actual beef and mutton sold off the farm, 

 at least one-half ought to have resulted from home-grown 

 foods. It is from these home-grown foods that the chief 

 profit is obtained, and it is the manure bill rather than 

 the cake bill that should flatter the farmer's pride. 



Stocks of dairy cattle in particular require ample provision 

 of fodder and roots during the winter. They also require a 

 considerable amount of grazing ground to provide them with 

 exercise and feeding during the whole year. Phosphatic 

 fertilizers are especially valuable in maintaining the growth 

 of grass late into the winter. Pastures fertilized with 

 phosphates recover quickly from adverse seasons. 



It is difficult in practice to put all such principles into 

 effect, as local considerations and prices may prevent their 

 application in detail. The proper use of artificial manures 

 gives a much greater scope for management of those details. 

 To avoid disease the interval of years between two identical 

 crops should be as long as possible. By alternating one 

 cereal with another, and one root crop with another, much 

 can be done in this direction. Weeds promote disease, and 



