106 EXPERIMENT STATION KECOED. 



One of the greatest needs in investig-ntion along this line is to deal 

 Avith the subject in its diflerent phases, rather than to consider it for 

 purposes of research in extenso. Soil fertility in itself is not a proj- 

 ect. It is a grand division of agriculture embracing a score, per- 

 haps hundreds, of projects. And if we are to learn anything more 

 about soil fertility than that it is the ability to produce crops, and 

 more about its maintenance than the calculated amounts of nutrients 

 removed and the fertilizing constituents needed to make good this 

 draft, we nuist separate this great subject into its different phases 

 and prosecute the individual research along narrow lines. 



