24 



Journal of Agricultural Research 



Vol. XVI, No. I 



It appears from data scattered through Wolff's ^ tables that in some 

 cases the magnesium content exceeds that of calcium, especially in the 

 beet family. In the leaves of these plants the calcium usually much 

 exceeds magnesium, while the reverse holds for the roots. In the 

 analysis given by Wolff ^ lime exceeds magnesia in spinach in an ap- 

 proximately 2 to I ratio. In Table IV the calcium-magnesium ratio is 

 shown for each experimental plot. 



Table IV. — Calciuin-magnesium ratio in ash of spinach plants. Lime {CaO)=i 



It will be noted that magnesia exceeds lime in every case, regardless 

 of the nature of the substances applied, except in that of the tops in the 

 plot receiving lime, in which the lime exceeds the magnesia. Spinach 

 seems to be even a more pronounced user of magnesium than the sugar 

 beet. The field notes show that the plot receiving magnesium carbonate 

 was somewhat better than that receiving calcium carbonate. Unfor- 

 tunately no sample from the magnesium-carbonate plot was ashed. 



SUMMARY 



Spinach plants grown on the grounds of the Virginia Truck Experi- 

 ment Station at Norfolk in beds given heavy treatments of fertilizer 

 salts, singly and in mixtures, gave best results in plots receiving a com- 

 plete mixture having a basic or neutral character in the soil (sodium 

 nitrate, basic slag, and potassium sulphate) ; next best with acid phos- 

 phate and with sodium sulphate ; poor in plots receiving heavy treatments 

 of sodium chlorid, sodium nitrate, and acid complete mixture (i to 2 tons 

 per acre); poorest with potassium chlorid. 



A study of the ash showed the highest total ash in the tops in plots 

 with sodium chlorid, calcium carbonate, acid phosphate, and manure; 

 lowest with potassium chlorid and basic complete mixture. The highest 

 ash was in roots accompanied with acid phosphate and manure, the lowest 

 with potassium chlorid and sodium salts. General excellent condition of 



' Wolff, E. aschen-analysen. T. 2, p. 42-50. Berlin. 



2 Wolff, E. op. ai, p. 128. 



