1887.] PUBLIC DOCUMENT — No. 33. 



Plat II. 



89 



Plat III. 



Whole Potato, 

 One-half a Potato, 



100 lbs. ground bones 

 and 96 lbs. potash- 

 magnesia sulphate. 



Total. 

 1,250 



974 



2,224 



A careful study of the above tables leads to the following 

 conclusions : — 



1. Medium-sized whole potatoes give better results than 

 half potatoes obtained from tubers of a corresponding size. 



2. Disregarding the results of the first year, when previously 

 existing liberal resources of plant food are apt to render the in- 

 fluence of an additional supply of manurial substances less 

 marked, it appears that the sulphate of potash produced better 

 results in our case than the muriate of potash. 



3. The premature dying out of the vines, accompanied by 

 blight or scab, or both, must be considered a controlling cause 

 of the exceptionally large proportions of small potatoes. 



B. — Observations with Scabby Potatoes. 



These experiments were inaugurated during the past season 

 for the purpose of inquiring into the circumstances which con- 

 trol the development and the propagation of the "scab" on 

 potatoes. 



The first year's work in this connection has been confined to 

 the task of observing the behavior of scabby potatoes as seed 

 potatoes, under some definite previous treatment. To prevent 



