308 Wisconsin State Hoeticultueal Society. 



in one hundred weight parts of the specified constituents. This 

 course has been adopted to render the changes which occur in 

 that direction more prominent. I gives the ash constituents of 

 the unfertilized wild purple grape, from the original locality 

 (1876) ; II, those of unfertilized Concord grape, from the college 

 vineyard (1876) ; III, of fertilized wild purple grape, from college 

 vineyard (1876) ; IV, of fertilized Concord grape, from experi- 

 mental plat (1876) : 



I. II. 



Potassium oxide 52.54 per cent. 67.70 per cent. 



Calcium oxide 22.93 " 13.39 " 



Magnesium oxide 5.77 ♦' 3.67 " 



Ferric oxide 0.81 " 0.47 



Pliosphoric acid 17.95 " 14.77 



100.00 100.00 



Sugar in juice (1877) 8.22 per cent. 13.89 per cent. 



III. IV. 



Potassium oxide 66.35 per cent. 69.68 per cent. 



Calcium cxide 15.08 " 9.84 " 



Magnesium oxide 4.15 " 3.91 " 



Ferric oxide 0.57 " 0,54 " 



Phosphoric acid 13.85 " 16.03 



100.00 100.00 



Sugar in juice (1877) 13.67 per cent. 15.43 per cent. 



The fertilized vines appeared, on the whole, more vigorous, and 

 the leaves, as a rule, retained their vitality longer in autumn than 

 in the case of the unfertilized ones ; they escaped repeatedly a 

 serious attack of mildew when the remainder of the vineyard suf- 

 fered with it more or less. The sugar seemed to be somewhat 

 increased in the fertilized fruit of the Concord grape, and had 

 increased one-third in quantity in the wild purple grape. The 

 increase of sugar was accompanied by a marked increase in po- 

 tassa, and, at the same time, a remarkably reduced percentage of 

 lime in the inorganic portion of the grape. The influence of fer- 

 tilization on the composition and the character of the fruit mani- 

 fested itself in a higher degree in the case of the native wild 

 grape than in the case of the improved variety. The results of 

 these experiments afford an additional illustration to the opinion 



