SPECIAL REPORT FOR YEAR I914. 33 



Several factors intervened which influenced the accuracy of 

 the results, but so far as could be judged, the application of 300 

 pounds of sulphur to this land produced no appreciable effects 

 in reducing common scab the present season. The potatoes 

 from this plot were equally badly incrusted with scab spots as 

 those produced upon the adjoining checks — practically all of 

 them being unsalable except for starch making. Where 500 

 pounds of sulphur was used there were fewer tubers thoroughly 

 covered with scabs and a small per cent of the crop here was 

 merchantable. Where 1000 pounds of sulphur was applied per 

 acre, fully 75 per cent of the crop was suitable for table purposes 

 and it was estimated that at least one-third of these were free 

 from scab. 



Based upon the figures alone, it would seem that the larger 

 amount of sulphur materially reduced the amount of scab on 

 the crop for the current year. There is always the possibility 

 that on large plots of land like these the soil is unequally 

 infected or some outside factor interferes. However, the check 

 alongside of these plots which received the heaviest application 

 of sulphur produced fully as much scab on the crop as on any 

 other part of the field. Before the plots were planted a record 

 w^as made of the fact that the owner of the land stated that 

 according to his best recollection the soil where the heavier 

 amounts of sulphur were applied was, if anything, the most 

 seriously infected of any on the field. He was not so positive 

 of this fact after the results were obtained at digging time, thus 

 leaving this question somewhat in doubt. 



The following paragraph quoted from a recent publication 

 of the Cornell Experiment Station is a brief summary of some 

 quite extended experiments made at that institution along the 

 lines under consideration. 



"From our work on sulfur treatment of soil against potato 

 scab it is evident that by application of sulfur in sufficient 

 quantity — 450 to 900 pounds per acre — if the application is 

 made broadcast and the sulfur is thoroughly mixed with about 

 two inches of the surface soil just before the potatoes are 

 planted, the amount of scab can be considerably reduced, 

 especially by the heavier application of sulfur. * * * ij-j ^o 

 case, however, even by the heaviest of the tested applications of 

 sulfur, was the scab entirelv eliminated." 



