56 THE EEPOET OP THE No. 36 



ing in our cellars, I bought a Niagara Dusting machine and have had no reason 

 since to regret it. Since then we used this outfit in our orchards and on our 

 potatoes with great success and on account of an educational point of view, 

 I have purchased a powerful ibean spraying rig. I am satisfied that in a large 

 orchard like ours, and especially in certain seasons, when the time factor is the all- 

 important one, dusting has come to stay in our Province. Let me say again that 

 in our orchards the Codling moth is the most destructive pest we have to control, 

 in other districts it is the Curculio. but at home we have no trouble with the 

 latter pest. 



Things were running rather smoothly in our Province, and Mr. Petch and 

 myself were making comparisons in dusting and spraying our orchards, and we had 

 all confidence in lime sulphur wash as a fungicide, when our friend Mr. George 

 Sanders sprung a surprise on us, in -a paper he read before our Society in con- 

 vention at Macdonald College, on the 5th of December 1917. Mr. Sanders, in 

 due justice to this paper, took the precaution to state that what he told us was 

 applied to Nova Scotia conditions as he could not pronounce himself about con- 

 ditions in Quebec. However, his stand against lime sulphur wash, especially in 

 combination with arsenate of lead, was so strong and his talking for Bordeaux so 

 convincing that we could not help thinking that his opinion would have some 

 strong weight upon such practical fruit-growers and Entomologists as were there 

 hearing him. I can but mention Prof. Macoun and Dr. Hewitt. You remem- 

 ber that his thesis was that lime sulphur did actually spray the apples of the trees. 

 I went back to Oka with the idea of putting on again some practical experi- 

 ments to determine, for my own use, if that thesis was true even in using the new 

 spray gun .and power behind it. I will not relate here that experiment, which 

 you can find in full in the report of the Entomological Society of Ontario in 1919. 

 The orchard was well chosen, all varieties being the same (Wealthies) , the bloom 

 on all plots being excellent. On the first plot, we used Boaxdeaux mixture, 

 4-4-40, the usual one, sprayed on the trees; we dusted sulphur-talc and arsenate 

 of lead, 40-50-10 on the second plot, sprayed lime sulphur-arsenate of lead on the 

 third plot ; dusted dry Bordeaux and calcium arsenate on the fourth plot ; sprayed 

 the new formula of Bordeaux mixture, 2-10-40, on the 5th plot, and dusted my own 

 combination of sulphur-hydrated lime and arsenate of lime, 15-80-5. on the 6th 

 and last plot. The cheapest dusting mixture was the last one. No injury what- 

 ever was noticed either on the lime-sulphur-arsenate of lead plot, or the dusted 

 sulphur-hydrated lime and calcium arsenate plots. We cannot therefore advocate 

 returning to Bordeaux mixture in our Province, as we had such a large crop of 

 apples that year on the lime sulphur plot that we had to thin them. 



We use exclusively now in our sprayings or dusting propositions arsenate of 

 lime as a contact poison in combination with either lime sulphur or the dry 

 sulphur when dusted on the trees, adding hydrated lime in the last case to safe- 

 guard the application and reduce the costs as a filler. In orchards where the scab 

 is not really bad, we do not use much sulphur and find that 5 lbs. of calcium arsen- 

 ate will control effectively Codling Moth when we do not get, like the past sea- 

 son, an outbreak of a second brood. 



1 may add that dry Bordeaux is freely used also in the Province but even there 

 we get the russetting from the Bordeaux which we avoid with the lime sulphur 

 spray. 



Last year a committee appointed by our Society, with Prof. Bunting of Mac- 

 donald College as chairman, Prof. Dickson, Prof. Lochhead, Mr. Petch and the 

 writer on the board, printed a Calendar which Macdonald 'College sent out all 

 over the Province. 



