44 EXPERIMENT FARM AT SOUTHERN PINES, N. C. 



APPLYING FERTILIZERS. 



Three series of combinations of the principal plant 

 foods are now under way at this Experiment Farm. One 

 series is devoted to the study of the effect of potash; the 

 second to the effect of nitrogen; the third to the effect of 

 phosphoric acid. In each series the quantities range from 

 a small amount of fertilizer to what may be considered an 

 excess. In the four illustrations on the pages following 

 the effect of fertilizers on sweet potatoes in some of the 

 experimental plots is illustrated. In the first illustration is 

 shown the actual yield obtained from one plot which 

 received no fertilizer (the plots in this series contain ^ of 

 an acre each). The yield calculated to an acre was 30 



