42 rt EXPERIMENT STATION. [Jan. 



Evidently, then, the concentrate is the cheapest material by 

 far. It is also evident that at the strengths advised by their 

 makers, the other substances will have much less of the active 

 agent present, and should be far less effective than the con- 

 centrate. 



On the other hand, many who have used these materials 

 report good results. Is this due to defective observations, 

 prei'udice in favor of materials so easily handled, or is it cor- 

 rect? If the latter, the question at once arises whether the 

 concentrate is not stronger at 1 to 8 than is really necessary, 

 and whether the other weaker materials are not, after all, 

 strong enough for the work. To answer this, extensive field 

 experiments under all kinds of conditions will be needed. It 

 is possible that for years we have been using the concentrate 

 stronger than is necessary, and that a greater dilution, bringing 

 the percentage of polysulfide sulfur per barrel of spray down 

 from 3.5 to about 1.25 per cent, would give equally good re- 

 sults. If this should prove to be true, the relative costs of 

 the different materials would not be greatly affected, however, 

 and the concentrate would in any case be the cheapest of the 

 four by a considerable amount. 



Extension Work. 



There has been the usual demand upon this department for 

 work of an Extension nature. Rather more than a quarter of 

 the entire time of one man has been required to attend to 

 duties of this kind. Correspondence, telephone and office calls, 

 visits to places where assistance was needed, fumigation work, 

 the preparation and demonstration of exhibits at fairs and 

 during Farmers' Week, have made up this total. 



The College Apiary, 



The care of the College Apiary was under the supervision of 

 Mr. J. L. Byard until about the middle of July. Unfortu- 

 nately, Mr. Byard was taken ill at that time, and^ during the 

 remainder of the year his work was necessarily carried on by 

 the men in this department.- Had this not been done, the 

 colonies of bees woidd have been lost and the beekeeping 



