CULTIVATION. 177 



The following results were furnished by the manuring 

 experiments conducted in the Spalt experimental hop garden 

 in 1895, reported by Kraus' : — 



The cones of the unmanured plots were uniform in 

 development, mostly very ripe and partly weather-beaten. 

 Those from the plots dressed with nitrate of soda and super- 

 phosphate were better in colour but less satisfactorily 

 developed ; and similar results were obtained from the plots 

 treated with the potash salts, except that many of the cones- 

 were small. In view of the high requirements of the hop- 

 plant as regards potash, Kraus recommends experiments 

 directed to the elucidation of this question, and expresses the 

 opinion that, given a sufficiency of nitrogen and phosphoric 

 acid, an addition of potash would certainly prove beneficial on 

 soils deficient in that substance. Furthermore, on the basis 

 of a series of experiments on the manuring of hops, he 

 arrived at the conviction that, by maintaining the correct 

 proportion between nitrogen, phosphoric acid, and potash, 

 better results in point of quality of produce can be obtained 

 than when stall manure is used exclusively. If, however, 

 the proper ratio be neglected, artificial manures may furnish 

 bad results, particularly in the case of nitrate of soda, which 

 produces coarse and irregular cones when used in excess. 



1 Wochenschrift des landw. Veremes m Baiern, vol. Ixxsrvi. 



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