VALUE OF FARMYARD MANURE 



97 



there are plots showing every combination between the various 

 mineral and nitrogenous dressings employed. 



The mineral manures, the dung and the rape cake, are 



TABLE XXXIX. Experiments on Mangolds, Barn Field, beginning 

 1876. Quantities of Manures per acre per annum. 



* Equal parts Sulphate and Muriate Ammonia of Commerce. 

 t The addition of Potash to Plot 2 began in 1895. 



ploughed in just before seeding, the ammonium-salts and 

 nitrate of soda are sown as top-dressings. 



The seed was dibbled in the earlier years of the experiment ; 

 it is now drilled, 26 inches between the rows, and the plants 

 are singled out to 10 inches apart. 



The following tables give, (XL.) the average weight of roots 

 grown on each plot during the thirty-four years, 1876-1912 ; * 

 (XLI.) the weight of roots and leaves grown in the best season, 

 1900. 



A first inspection of the results shows the enormous value 

 of farmyard manure in growing mangolds, especially when they 

 are grown continuously on the same land. In favourable 

 seasons it is possible to obtain good crops by the aid of 

 manures containing no organic matter, as seen in 1900 ; but 

 in ordinary years the bad texture of the soil and its tendency 

 to lose water on account of the lack of humus affect both the 

 germination of the seed and the growth of the plant in its early 

 stages. It will be convenient, therefore, to consider separately 



* 1885, 1901, and 1908 omitted. 



G 



