94 THE CHEMISTKY OF THE FARM. 



fibre than older grass, and is consequently more nourish- 

 ing. The same comparison may be made between young 

 clover and that which is allowed to mature for hay. 

 Fodder crops should be cut for hay immediately full 

 bloom is reached; after this point the quality of the hay 

 will considerably deteriorate. 



While fodder crops deteriorate towards maturity, 

 from the conversion of soluble carbo-hydrates into fibre, 

 crops such as potatos and mangel improve, the carbo- 

 hydrates produced in their case being respectively starch 

 and sugar, both of them substances of great feeding 

 value. 



The influence of high manuring on the composition 

 of a crop is generally considerable. A luxuriant crop 

 will always contain more water than one in less active 

 growth. Very large mangels often contain only 6 per 

 cent, of dry matter, while in quite small roots the pro- 

 portion may be as high as 15 per cent. Luxuriance also 

 retards maturity. A heavily manured mangel will con- 

 tain, at the same date, a much smaller proportion of 

 sugar than a similar mangel grown on poorer soil. The 

 result of liberal nitrogenous manuring is thus not only to 

 increase the bulk of the crop, but also generally to 

 diminish the proportion of carbo-hydrates, and increase 

 the nitrogen, ash constituents, and water. In highly 

 manured crops a smaller proportion of the nitrogen will 

 exist as albuminoids than in crops less heavily manured 

 and more mature. Thus, in a crop of mangels of 18 tons 

 per acre, manured with farmyard manure, the albuminoid 

 nitrogen amounted to 38 per cent, of the total nitrogen ; 

 while in a crop of 28 tons, receiving nitrate of soda and 

 superphosphate in addition to the dung, the albuminoid 



