191.3. 



rUBLIC DOCUMENT — No. 31. 



159 



of eitli(>r ill tlic top-dressing produces a iiotaldy lower average 

 weight of roots. The mediimi applications of phosphate and of 

 potash salts produce the highest average weights of roots. 



Ilousseaux and IJrioux ^ found the heaviest roots where 

 manure and chemicals were combined, and it is of interest that 

 the fresh weight was 2, GOO grams, which is practically the same 

 as the weight of our roots from the plots receiving top-dressings 

 of medium amounts of fertilizers. 



Effect of Seasoti of Application of Nitrate of Soda on Weight of Roots. 



Spring Application (Grams). 



Plot 

 Number. 



Low, 



Medium, . 

 High, 



Average, 



1,025 

 1,200 

 1,330 



1,207 



2,545 

 2,733 

 2,854 



2,711 



1,852 

 2.770 



Spring and Summer Applications (Grams). 



Low, 



Medium, . 

 High. 



Average, 



895 



1,211 



730 



945 



2,538 

 3,089 

 2,227 



2,618 



The summer top-dressing with nitrate has produced smaller 

 mature roots than the spring top-dressing, in both years 1908 

 and 1910. On the other hand, the roots of 1911, taken at the 

 end of the cutting season in the summer, show variable results, 

 with, the average weight heavier on the summer-dressed plots. 



» Loc. cit., p. 312. 



