Conservation of Nitrogen. 193 



was due to poisoning by the large amounts of this com- 

 pound in the corn. While this is probably not true, the 

 excess of nitrate taken up by the plant not only makes 

 the corn fodder less valuable but depletes the soil of ni- 

 trogen. The nitrate not taken up by the plant is leached 

 from the soil during the winter and spring and is lost. 



The ideal condition would be to have the nitrates 

 formed at the time they are needed by the plant and to 

 have no excess. But this is not possible, an excess must 

 be formed in order to obtain a maximum crop since the 

 roots of the plants do not reach each soil particle. It is 

 estimated that for each pound of nitrogen removed from 

 the soil in the crop, four pounds are lost in drainage 

 water. The farmer can do something to conserve the 

 nitrogen of his soil. If a crop has been removed in late 

 summer or early fall, there will be nothing to use the 

 nitrate that will be formed, hence it will be lost during 

 the winter. If a cover crop had been planted it would 

 have absorbed the nitrate, building the nitrogen up into 

 its tissue and preventing its loss from the soil. If the 

 cover crop is plowed under in the spring, it will be de- 

 composed, and not only the nitrogen it contains, but the 

 phosphorus and potash as well, rendered available for 

 the next crop. In orchards not under sod the cover crop 

 is especially beneficial. If the cover crop is one of the 

 leguminous plants, the soil may even be enriched in ni- 

 trogen as will be seen later. 



It is now recognized that the process of fallowing the 

 land is an excellent means of robbing the soil of its nitro- 

 gen because, while the soil is bare, the frequent stirring 

 establishes favorable conditions for nitrification, but as 

 there is no crop present to use the nitrates which are 

 formed they are lost in the drainage water. 



