Jan. 6, 1919 



Ash Absorption by Spinach 



17 



Another review of the plots was made on December i, 191 5, with 

 similar results. 



The "best" plot in the whole experiment was that receiving the basic 

 complete mixture. 



Those having acid phosphate and sodium sulphate were "excellent." 



"Good" would be said of plots receiving magnesium carbonate; some- 

 what less so, were those receiving calcium carbonate, which gave a very 

 deep green color, and manure, especially the part of the bed receiving the 

 lighter application. 



The four plots found to be "poor" were those having sodium chlorid, 

 sodium nitrate, and acid complete mixture. Poorest of all was potash. 

 All poor plots were alike in having a crusted soil surface, with a suggestion 

 of moisture. 



At this stage samples were taken from several of the beds for ash 

 analysis at Washington. 



ASH DETERMINATIONS 



The plants, after being divided into roots and tops, were ashed in an 

 electric furnace at a low red heat of approximately 600° C. The total 

 ash being determined, the chief constituents were worked out by the 

 methods recommended by the Association of Official Agricultural Chem- 

 ists.' 



The results are given in Table I. In the first section the lesults are 

 calculated as percentages of the air-dry weight of the plant material, 

 while in the second section the individual constituents are calculated as 

 percentages of the total ash. 



Table I. — Ash constituents of spinach 



CALCULATED AS PERCENTAGES OF DRY MATERIAL 



1 Wiley, H. W., ED. oppiciai, and provisionai, methods of analysis, association op officlvl 



AGRICULTITRAL CHEMISTS, AS COMPILED BY THE COMMITTEE ON REVISION OF METHODS. U. S. Dept. 



Agr. Bur. Chem. Bui. 107 (rev.). 271 p., 13 fig. 1908, 

 92801°— 19 2 



