THE WHEAT CULTURIST. 177 



WHY NITROGENOUS MANURES ARE REQUIRED FOR 



WHEAT. 



Although an application of superphosphate of lime 

 will grow a large crop of turnips with the aid of a very 

 little organic manure, and red clover will grow luxu- 

 riantly on a medium-conditioned soil, with the aid of 

 the same application, or a little plaster, yet no grain 

 crop will reach the maximum on such a soil, no matter 

 how rich you make it in all the mineral and inorganic 

 elements, without a liberal application of nitrogenous, 

 well-saved stall manure, or its equivalent in Peruvian 

 guano or ammonia salts. J. B. Lawes, in his long series 

 of experiments, ascertained conclusively that where 

 every mineral element was in the soil necessary for a 

 maximum crop of wheat, the yield of wheat on an acre 

 was doubled by the aid of two hundred pounds of 

 sulphate of ammonia alone ; and Indian corn being 

 a great feeder, it is in much greater need of more, 

 nitrogen (ammonia) than the more dainty wheat plant : 

 in fact it may be truly said, the more ammonia the 

 more corn, provided the soil is well drained and tilled. 

 As neither the stalks nor grain of cereal plants con- 

 tain nitrogen in anything like the proportion in which 

 it is found in peas, beans, clover, and other legumi- 

 nous plants, Mr. Lawes has come to the very reasona- 

 ble conclusion that wheat, barley, rye, timothy, etc., 

 destroy nitrogen during the process of their growth, or 

 rather that nitrogenous compounds are used up and 

 destroyed in making other matters in the soil into solu- 

 ble plant food. Liebig says that quicklime applied to 

 the soil, particularly to clay, dissolves the silicates into 

 soluble plant food. If this is so, auplus forte raison, 



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