1913.] 



PUBLIC DOCUMENT — No. 31. 



93 



The yield was small, however, hoth on the treated tiles and the 

 checks. 



The series treated with carbon bisulfid showed some results, 

 the check tiles averaging 50 per cent, scab and the treated tiles 

 showing an average of 20 per cent. 



It can be seen that this year's results are showing some im- 

 provement over those of preceding years, and by elimination 

 only the most useful compounds are to be used hereafter, with 

 perhaps one or two additions. 



1 Numbers omitted were used as check tile. Potatoes treated exactly as in preceding experi- 

 ments. 



In 1912 the experiments were carried on in a similar man- 

 ner, but for the most part chemical solids were used, with the 



