In contradistinction to mdngolds and potatoes, grain crops find in the rich soil of 

 the experimental field, a sufficiency of potash and phosphoric acid, even where 

 these foods have not artificially been supplied, whereas on the other hand they 

 are especially responsive to a dressing of nitrogen. If, in the case of winter-wheat 

 and winter-rye, the effect is perhaps not so marked, this is to be explained by 

 the rotation. Rye succeeds peas, and wheat, beans, and as both these crops leave 

 the land relatively rich in nitrogen, it is only to be expected that the effects 

 of a nitrogenous dressing will be somewhat less evident. Over and above this, 

 it should be noted that crops dressed with nitrogen, were as a rule badly laid, 

 and consequently did not thresh so well. With the spring- sown grain, the case is 

 different, barley following mangolds, and spring-wheat, potatoes. There the demand 

 for nitrogen is much greater and the effect of a nitrogenous dressing much more 

 clearly evidenced, as may be seen from the illustrations of the barley plots. 

 Prominence may here be given to the fact, that not only nitrogen, but also potash, 

 has a very marked and characteristic effect on colour; a dressing of potash 

 imparting to the plant a somewhat lighter and yellower green. 

 In contrast again to grain crops, the leguminosae shew practically no benefit from 

 an artificial supply of nitrogen, with exceptions in the cases of peas and kidney- 

 beans, where a slight increase is noted from the addition of nitrogen alone. This 

 is explained by the fact that prior to the formation of the nitrogen -acquiring root 

 nodules, the leguminous plant will experience a period of starvation if no available 



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