142 AGRICULTURAL EXPERIMENT STATION. [Jan. 



in the preceding season. The seed potatoes used had been 

 carefully selected from our own crop, raised during the pre- 

 ceding season, on the same plats. 



The young crop was hoed June 9. The difference in the 

 plats was quite marked July 24 : Plat No. 1, fertilized with 

 muriate of potash, had the largest foliage and looked darker 

 green than the remainder; No. 3, fertilized with sulphate of 

 potash, looked next best. A blight on the leaves, which 

 showed itself during the first week of August, prematurely 

 terminated the experiment ; the vines upon all plats died 

 soon after. The crop was harvested Aug. 26. The potatoes 

 from all the plats suffered severely from scab. 



The exceptionally large proportion of small potatoes oT)- 

 tained, in particular, from Plats No. 2 and 3, as well as the 

 low percentage of solids in the potatoes tested, proved the 

 premature termination of a healthful condition of the entire 

 crop. The normal growth of the tubers came apparently to 

 a standstill soon after the first examination for solids had 

 been made (July 24). The results seemed to indicate a 

 connection between " blight" and " scab," and left scarcely 

 any doubt about the circumstance, that either the one or the 

 other, or both jointly, had contributed directly or indirectly 

 towards the partial failure of the crop for the two succeed- 

 ing seasons. 



It was decided, in sight of these facts, to continue the ex- 

 periments in 1886 upon the same field, with some modifica- 

 tions, to ascertain, if possible, whether the main influence 

 reo-arding the results in our past observation had to be 

 ascribed to atmospheric agencies, or to the condition of the 

 soil and the fertilizer applied, or to the quality of the seed 

 potato used. 



1886. — The same field was used as in 1885. The land 

 was well prepared by ploughing and harrowing, April 27, 

 and subsequently fertilized, the same as in previous years. 

 The change regarding the character of the fertilize' appli-d, 

 consisted in using nearly tivice the amount of potash salts, 

 muriate and sulphate of potash, for the same area, in case of 

 Plats 1 and 3. A second important change from our pre- 

 vious practice consisted in securing first quality seed pota- 

 toes. — in particular, /ree from scab The same variety — 



