1913.] PUBLIC DOCUMENT — No. 31. 167 



The percentages of sugar vary independently of the various 

 kinds of top-dressing, since there are wide variations in the 

 results for Plots Y, 11 and 34, on which identical amounts of 

 fertilizers had been applied. 



The season of application of nitrate of soda apparently did 

 not influence the percentages of sugar in the fall roots, but there 

 is less apparent exhaustion in the 1911 roots where nitrate had 

 been applied in the spring (Plots 31 and 34). 



Since the variations in sugar showed so little relationship to 

 the scheme of fertilization, it was not deemed worth while 

 to pursue the investigation into the effects upon fiber and pen- 

 tosans, as there are too many factors to be correlated. 



Summarizing the results briefly, it has been shown that the 

 medium amounts of chemicals in this series of fertilizer tests 

 produced the most favorable results on size and composition of 

 the asparagus roots. 



The absence of any one of the three fertilizers resulted in 

 depression of weight of root, which was accompanied by a de- 

 pression in nitrogen in the absence of nitrate of soda, and by a 

 depression in the potash and ash in the absence of muriate of 

 potash. 



The summer top-dressing with nitrate of soda produced 

 smaller roots than the spring top-dressing, but with notably 

 higher percentages of nitrogen. The exhaustion of the roots by 

 the cropping season was most manifest in the percentages of 

 sugar in the roots from the summer top-dressed plots. 



The thanks of the author are due Messrs. Haskins and Walker 

 for the analytical data on ash and ash constituents, to Dr. 

 W. P. Brooks, director, for the fertilizer data, and to Dr. J. B. 

 Lindsey, chemist, for many timely suggestions. 



