94 



EXPERIMENT STATION. 



[Jan. 



exception of the formalin treatment, which remained the same 

 as the preceding years. 



The bj-product A treatment showed good results, especially 

 when applied dry in 500-gram amounts to the pot area. Even 

 in smaller quantities a decided benefit seemed to be obtained, 

 as can be seen from the following summary : — 



Substance used. 



Amount 

 used. Dry 

 (Grams). 



Per Cent. 



Amount 

 used, Wet 

 (Grams). 



Per Cent. 



By-product A, 

 By-product A, 

 By-product A, 

 Check, . 



100 

 300 

 .500 



100 

 200 

 300 



■ Apparently this substance has a good effect. The yield of 

 tubers was in all cases good. If the substance were applied at 

 this rate (500 grams to 3 square feet) it would mean about Y 

 tons to the acre, but it may be shown that a smaller quantity 

 would be sufficient. Much more work is necessary before any 

 definite opinion can be advanced as to the actual worth of the 

 substance. 



The sulfur treatment showed slightly beneficial results, the 

 different tiles and check showing the scab present in the follow- 

 ing amounts: — 



Sulfur, 50 grams, 70 per cent. scab. 



Sulfur, 100 grams, ....... 50 per cent. scab. 



Sulfur, 200 grams, 60 per cent. scab. 



Cheek, ......... 85 per cent. scab. 



The yield of tubers was good in the case of the sulfur treat- 

 ment. 



The naphthalene treatment showed no results, with very little 

 yield of tubers. 



The steam-sterilized tiles, sterilized to a depth of 6 inches, 

 and corresponding check showed scab present in the following 

 amounts : — 



Steam-sterilized soil (a), 60 per cent. scab. 



Steam-sterilized soil (b), 40 per cent. scab. 



Steam-sterilized soil (c), 30 per cent. scab. 



Check, . . . 60 per cent. scab. 



